From jlandrigan at pol.net  Wed Aug  3 14:37:40 2011
From: jlandrigan at pol.net (John Landrigan)
Date: Wed, 3 Aug 2011 14:37:40 -0400
Subject: [HBR] Quartz Crystal Oscillator
In-Reply-To: <1716042953.16603371312396515098.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
Message-ID: <901896344.16604021312396660824.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>

How practical is this device (Russian tube type quartz crystal oscillator) to use in place of a FT-243 quartz crystal as the second oscillator for a 50 KHz 2nd IF in an HBR styled receiver?
Ebay # 260829157003

I was hoping to procure a wiring diagram and then put a capacitor in series to adjust from the 59 KHz to the 50 KHz IF frequency.

John KA4RXP and Jody KG4VES



From daileyservices at qwest.net  Wed Aug  3 14:45:34 2011
From: daileyservices at qwest.net (TC Dailey)
Date: Wed, 3 Aug 2011 12:45:34 -0600
Subject: [HBR] Quartz Crystal Oscillator
References: <901896344.16604021312396660824.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
Message-ID: <BBEDCEBFC59543CB9D5951296C17F54F@w0eaj>

Pulling that down 9kc might be a bit of a "budge" - 

From tshoppa at wmata.com  Wed Aug  3 14:50:02 2011
From: tshoppa at wmata.com (Shoppa, Tim)
Date: Wed, 3 Aug 2011 14:50:02 -0400
Subject: [HBR] Quartz Crystal Oscillator
In-Reply-To: <901896344.16604021312396660824.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
References: <1716042953.16603371312396515098.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
	<901896344.16604021312396660824.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
Message-ID: <B136EDE3DF5EC441B6F08E0A7AB872450DCB139C1D@EX2K7-CMS-1.wmata.local>

I really doubt you'd be able to shift a 59 kHz crystal all the way to 50 kHz with a capacitor.

It depends on the cut of course but just for comparison: a 32kHz tuning fork crystal oscillator can be shifted up or down a few Hz with a capacitor.

OTOH you could probably repeak any 50kHz IF transformers for 59kHz just fine (maybe just maybe you'd take some turns off or tweak the built-in C's.)

For a 50kHz BFO that you'd want to be able to tweak up and down several kHz with the BFO knob, the LC tank is pretty ideal.

Tim N3QE

-----Original Message-----
From: hbr-bounces at mailman.qth.net [mailto:hbr-bounces at mailman.qth.net] On Behalf Of John Landrigan
Sent: Wednesday, August 03, 2011 2:38 PM
To: tetrode; HBR Reflector
Subject: [HBR] Quartz Crystal Oscillator

How practical is this device (Russian tube type quartz crystal oscillator) to use in place of a FT-243 quartz crystal as the second oscillator for a 50 KHz 2nd IF in an HBR styled receiver?
Ebay # 260829157003

I was hoping to procure a wiring diagram and then put a capacitor in series to adjust from the 59 KHz to the 50 KHz IF frequency.

John KA4RXP and Jody KG4VES


______________________________________________________________
HBR mailing list
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From wrcromwell at gmail.com  Wed Aug  3 17:19:07 2011
From: wrcromwell at gmail.com (Bill Cromwell)
Date: Wed, 03 Aug 2011 17:19:07 -0400
Subject: [HBR] [Glowbugs] Quartz Crystal Oscillator
In-Reply-To: <901896344.16604021312396660824.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
References: <901896344.16604021312396660824.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
Message-ID: <1312406347.1980.14.camel@lancelot>

On Wed, 2011-08-03 at 14:37 -0400, John Landrigan wrote:
> How practical is this device (Russian tube type quartz crystal oscillator) to use in place of a FT-243 quartz crystal as the second oscillator for a 50 KHz 2nd IF in an HBR styled receiver?
> Ebay # 260829157003
> 
> I was hoping to procure a wiring diagram and then put a capacitor in series to adjust from the 59 KHz to the 50 KHz IF frequency.
> 
> John KA4RXP and Jody KG4VES
> 
> 

Hi John,

Others have already pointed out the limits of rubberizing crystal
oscillators. For some perspective, at BFO frequencies for 3.395 mc I.F
strips (and filters) separate crystals are used for USB, LSB, and CW in
the rigs I have here because a single crystal does not want to 'stretch'
that far (about 3 kc or so) at those frequencies. Some radios with 9 mc
I.F. do rubber the crystal for USB, LSB, and CW. Some radios and filters
do not require a separate CW carrier. At 9 mc apparently we can more
reliably get the 3kc or so (up to 5 kc) that is required by switching
the "rubberizing" elements.

I have used the 455kc L-C free running oscillators as BFO in a tube
based Hammarlund and now in a Ten Tec receiver that is otherwise crystal
and PLL controlled. There are two BFO settings that are interactive,
touchy to align, and are switch selected for sideband (and USB or LSB
can be programmed). I much preferred the variable BFO on the Hammarlund
to the binary choice on the Ten Tec (but that isn't programmable). At
455 kc there is negligible warmup drift on the tubed radio and not even
noticeable on the Ten Tec. At 50 kc the stability from turn-on should be
even better. I agree with the suggestion to use a variable L-C
free-running BFO. If you really are talking about a mixer closer to the
antenna from a higher frequency you probably wouldn't be talking about a
59 kc oscillator.

73,

Bill  KU8H


From jwiley at alaska.net  Wed Aug  3 15:11:30 2011
From: jwiley at alaska.net (Jim Wiley)
Date: Wed, 03 Aug 2011 11:11:30 -0800
Subject: [HBR] [Glowbugs] Quartz Crystal Oscillator
In-Reply-To: <901896344.16604021312396660824.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
References: <901896344.16604021312396660824.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
Message-ID: <4E399D62.1030007@alaska.net>

John -


I doubt what you have in mind will work.   You are attempting to move 
the crystal almost 20% in frequency - which I think is not very likely.  
Such "rubbering" is usually limited to much less than 1% of the 
"nominal" crystal frequency.   Unless you are using a specially designed 
VXO (a so called variable crystal oscillator) - most crystals will only 
"move" on the order of 0.1% - which would be about 59 Hertz!  - rather 
less than the 9.5 kHz you are looking for.   These numbers may not be 
exact, and will change depending on the type of cut the crystal uses, 
and other factors, but you get the idea.


- Jim, KL7CC



John Landrigan wrote:
> How practical is this device (Russian tube type quartz crystal oscillator) to use in place of a FT-243 quartz crystal as the second oscillator for a 50 KHz 2nd IF in an HBR styled receiver?
> Ebay # 260829157003
>
> I was hoping to procure a wiring diagram and then put a capacitor in series to adjust from the 59 KHz to the 50 KHz IF frequency.
>
> John KA4RXP and Jody KG4VES
>
>
>   

From broehrig at aurora.edu  Wed Aug  3 15:14:41 2011
From: broehrig at aurora.edu (Robert Roehrig (K9EUI))
Date: Wed, 3 Aug 2011 14:14:41 -0500 (CDT)
Subject: [HBR] [Glowbugs] Quartz Crystal Oscillator
In-Reply-To: <901896344.16604021312396660824.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
Message-ID: <1049629196.3438837.1312398881700.JavaMail.root@mars.aurora.edu>




> How practical is this device (Russian tube type quartz crystal
> oscillator) to use in place of a FT-243 quartz crystal as the second
> oscillator for a 50 KHz 2nd IF in an HBR styled receiver?
> Ebay # 260829157003
> 
> I was hoping to procure a wiring diagram and then put a capacitor in
> series to adjust from the 59 KHz to the 50 KHz IF frequency.
> 
> John KA4RXP and Jody KG4VES

Are you using this as a BFO at 50 kHz or do you want to hetrodyne from some higher frequency 1st if to and IF of 50 kHz?  Big difference.  But I agree with John - you canno0t pull that xtal that far.



-- 
Bob Roehrig ITS
630-844-4898




From bjcbjc at gmail.com  Wed Aug  3 18:44:04 2011
From: bjcbjc at gmail.com (Brian Carling)
Date: Wed, 3 Aug 2011 18:44:04 -0400
Subject: [HBR] [Glowbugs] Quartz Crystal Oscillator
In-Reply-To: <901896344.16604021312396660824.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
References: <1716042953.16603371312396515098.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
	<901896344.16604021312396660824.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
Message-ID: <CAOS5NjvAkaUj6FHGtkAhysSUyRGnW3qiCLf0goPGUp1EKSBb7A@mail.gmail.com>

That's probably is not going to happen. If I understand correctly it is a
crystal oscillator running at 59 kilohertz. If that is correct then I doubt
that you could pull it down to 50 kHz with a capacitor.

Bry Carling
http://www.af4k.com
"Stay thirsty, my friends."
On Aug 3, 2011 2:37 PM, "John Landrigan" <jlandrigan at pol.net> wrote:
> How practical is this device (Russian tube type quartz crystal oscillator)
to use in place of a FT-243 quartz crystal as the second oscillator for a 50
KHz 2nd IF in an HBR styled receiver?
> Ebay # 260829157003
>
> I was hoping to procure a wiring diagram and then put a capacitor in
series to adjust from the 59 KHz to the 50 KHz IF frequency.
>
> John KA4RXP and Jody KG4VES
>
>
> --
> ZCZC
> This is a transmission from the Glowbugs list
> To unsubscribe from this group, send email to
> tetrode+unsubscribe at googlegroups.com
> For more options, visit this group at
> http://groups.google.com/group/tetrode?hl=en
> NNNN

From jlandrigan at pol.net  Thu Aug  4 16:19:40 2011
From: jlandrigan at pol.net (John Landrigan)
Date: Thu, 4 Aug 2011 16:19:40 -0400
Subject: [HBR] Quartz Crystal Oscillator
In-Reply-To: <263133910.16871961312489127660.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
Message-ID: <1951022331.16872141312489180441.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>

Now that I've gotten myself unconfused, here is what I am trying to do:
The HBR 16 variant that I am building up has a High Frequency L/C oscillator which mixes with the antenna input into an RF amplifier. The output from the first mixer goes to a Millen 1600 KHz IF transformer. The next step is to take this output and mix it with the 2nd oscillator, using the crystal I have, 1710 KHz, and put that output into a Miller 100 KHz 2nd IF transformer. There are two subsequent IF amplifiers that use similar Miller 100 KHz IF transformers.
Once I ever get that setup working, I would like to change things so that the output from the Millen 1600 KHz IF transformer mixes with a 455 KHz 2nd oscillator and IF transformer then into a crystal lattice filter, or into two subsequent 455 KHz IF amlifiers.
The next grandiosity is to find a means to develop a 2nd oscillator that will mix so that an output will be made available to either an 85 KHz IF or 50 KHz IF. It seems like the finding of crystals specific for 1685 KHz and 1650 KHz is not going to happen in this lifetime. Therefore, some type of L/C circuit is going to be in order. I was thinking that the Russian 59 KHz quartz crystal oscillator tube might prove usable somewhere in this mish-mash of thinking out loud.
John KA4RXP and Jody KG4VES



From n2ey at aol.com  Thu Aug  4 17:34:06 2011
From: n2ey at aol.com (n2ey at aol.com)
Date: Thu, 4 Aug 2011 17:34:06 -0400 (EDT)
Subject: [HBR] [Glowbugs] Quartz Crystal Oscillator
In-Reply-To: <1951022331.16872141312489180441.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
References: <1951022331.16872141312489180441.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
Message-ID: <8CE21055F28BFB2-1518-5A92@webmail-m129.sysops.aol.com>


 

 


 

 

-----Original Message-----
From: John Landrigan <jlandrigan at pol.net>



The next grandiosity is to find a means to develop a 2nd oscillator that will 
mix so that an output will be made available to either an 85 KHz IF or 50 KHz 
IF. It seems like the finding of crystals specific for 1685 KHz and 1650 KHz is 
not going to happen in this lifetime. 

Maybe not - but there are other possibilities.

You could use 842.5 kHz and 825 kHz xtals in a pentode oscillator (modified-Pierce, grid-plate) and double in the 
plate circuit. Or  561.667 kHz and 550kHz xtals and triple. There are probably FT-241s in those ranges. 

73 de Jim, N2EY

 

From ianmwilson73 at gmail.com  Thu Aug  4 17:50:40 2011
From: ianmwilson73 at gmail.com (Ian Wilson)
Date: Thu, 4 Aug 2011 14:50:40 -0700
Subject: [HBR] [Glowbugs] Quartz Crystal Oscillator
In-Reply-To: <8CE21055F28BFB2-1518-5A92@webmail-m129.sysops.aol.com>
References: <1951022331.16872141312489180441.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
	<8CE21055F28BFB2-1518-5A92@webmail-m129.sysops.aol.com>
Message-ID: <CAEz8jcRDz+P2Wza1gP9epy3gypy1FsSv2QTTPQV0Rz5JhSmCNA@mail.gmail.com>

I would think that with a good-quality inductor, air-variable capacitors, a
regulated supply,
and perhaps playing around with small compensating caps, a LC oscillator at
1650 or 1685 kc
would be stable enough. After all, this is the sort of frequency that most
tube VFOs are based at
before multiplication.

73, ian K3IMW

From radioconnection at gmail.com  Thu Aug  4 18:29:33 2011
From: radioconnection at gmail.com (Peter Bertini)
Date: Thu, 4 Aug 2011 18:29:33 -0400
Subject: [HBR] Quartz Crystal Oscillator
In-Reply-To: <1951022331.16872141312489180441.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
References: <263133910.16871961312489127660.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
	<1951022331.16872141312489180441.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
Message-ID: <CA+uDY2Sq8n0aUfY=4SgjjyvcNBkJn65HDezJTOC2mHekG==cXA@mail.gmail.com>

You can find a pair of  near 1685kHz
crystals in many half-lattice crystal filters,
as used in the Heathkit GR-54 and HR-10
receivers. Plenty of junker parts sets out
there.... the crystals will be a few kHz off
of 1685kHz, but they should work if you
are willing to move the IFs a bit.

Pete

On Thu, Aug 4, 2011 at 4:19 PM, John Landrigan <jlandrigan at pol.net> wrote:

> Now that I've gotten myself unconfused, here is what I am trying to do:
> The HBR 16 variant that I am building up has a High Frequency L/C
> oscillator which mixes with the antenna input into an RF amplifier. The
> output from the first mixer goes to a Millen 1600 KHz IF transformer. The
> next step is to take this output and mix it with the 2nd oscillator, using
> the crystal I have, 1710 KHz, and put that output into a Miller 100 KHz 2nd
> IF transformer. There are two subsequent IF amplifiers that use similar
> Miller 100 KHz IF transformers.
> Once I ever get that setup working, I would like to change things so that
> the output from the Millen 1600 KHz IF transformer mixes with a 455 KHz 2nd
> oscillator and IF transformer then into a crystal lattice filter, or into
> two subsequent 455 KHz IF amlifiers.
> The next grandiosity is to find a means to develop a 2nd oscillator that
> will mix so that an output will be made available to either an 85 KHz IF or
> 50 KHz IF. It seems like the finding of crystals specific for 1685 KHz and
> 1650 KHz is not going to happen in this lifetime. Therefore, some type of
> L/C circuit is going to be in order. I was thinking that the Russian 59 KHz
> quartz crystal oscillator tube might prove usable somewhere in this
> mish-mash of thinking out loud.
> John KA4RXP and Jody KG4VES
>
>
> ______________________________________________________________
> HBR mailing list
> Home: http://mailman.qth.net/mailman/listinfo/hbr
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:HBR at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>

From bjcbjc at gmail.com  Thu Aug  4 22:25:03 2011
From: bjcbjc at gmail.com (Brian Carling)
Date: Thu, 4 Aug 2011 22:25:03 -0400
Subject: [HBR] [Glowbugs] Quartz Crystal Oscillator
In-Reply-To: <8CE21055F28BFB2-1518-5A92@webmail-m129.sysops.aol.com>
References: <1951022331.16872141312489180441.JavaMail.root@zmcs02l-pol-08.portal.webmd.com>
	<8CE21055F28BFB2-1518-5A92@webmail-m129.sysops.aol.com>
Message-ID: <CAOS5NjsQR=QVoOqN29vuxd052i6jq7Saq3CpCb7htdK2kEHTHg@mail.gmail.com>

In this lifetime? Well, there ARE a few around certainly some that are close
to your desired 1685 kHz anyway.

I have some 1700 kHz crystals available in fact. Any use to you?

Regards - Brian, AF4K


On Thu, Aug 4, 2011 at 5:34 PM, <n2ey at aol.com> wrote:

>
>
>
>
>  -----Original Message-----
> From: John Landrigan <jlandrigan at pol.net>
>
>
>
> The next grandiosity is to find a means to develop a 2nd oscillator that will
>
> mix so that an output will be made available to either an 85 KHz IF or 50 KHz
>
> IF. It seems like the finding of crystals specific for 1685 KHz and 1650 KHz is
>
> not going to happen in this lifetime.
>
>
> Maybe not - but there are other possibilities.
>
>
> You could use 842.5 kHz and 825 kHz xtals in a pentode oscillator (modified-Pierce, grid-plate) and double in the
>
> plate circuit. Or  561.667 kHz and 550kHz xtals and triple. There are probably FT-241s in those ranges.
>
>
> 73 de Jim, N2EY
>
>   --
> ZCZC
> This is a transmission from the Glowbugs list
> To unsubscribe from this group, send email to
> tetrode+unsubscribe at googlegroups.com
> For more options, visit this group at
> http://groups.google.com/group/tetrode?hl=en
> NNNN
>



-- 
Regards - Bry, AF4K
"Stay thirsty, my friends!"

From waltah at earthlink.net  Sun Aug 14 12:10:50 2011
From: waltah at earthlink.net (Walt Hutchens)
Date: Sun, 14 Aug 2011 12:10:50 -0400
Subject: [HBR] The long, SLOW HBR project
In-Reply-To: <CA58138A.4FCE%waltah@earthlink.net>
Message-ID: <CA6D6BCA.6215%waltah@earthlink.net>

Well, THAT was interesting.

That VHF oscillation on turn-on?  Turned out to be not in the mixer, but in
the LO.   First time I've seen that.

The first couple of hours of work I was getting nowhere with it because it
was only showing up for a second or so at turn on.   I swapped mixer tubes,
no change.  Finally in desperation I put 100 ohm series resistors in the two
mixer grids ... NO CHANGE.

Because tuning the receiver changed the behavior and disabling the RF stage
did not, it had to be either the oscillator or the mixer.   I swapped LO
tubes, and suddenly the problem was solid:   Turn it on and the roaring
(very strong broadband noise covering everything else up) never goes away.

Flipped it upside down and began poking around the 12BZ6 LO with a wooden
lead pencil, and sure enough touching the LO control grid made the roaring
stop.   Touching the screen grid (oscillator plate) changed things and the
results varied slightly along the wire connecting the tube to the coil -- a
distance of maybe three inches.   Clearly in the oscillator section of that
tube AND clearly VHF.

(Why a lead pencil?  Because it is a resistor coupled through a tiny
capacitor to ground, namely, you.  It will eat significant energy from a VHF
circuit but have much less effect on HF signals.  Due caution necessary with
high voltages!)    

A 100 ohm resistor in series with the control grid mounted right at the tube
socket -- resistors for this purpose should have leads not over 1/4" long on
the socket side -- stopped the problem.

All the modern high gain triodes and many late pentodes will oscillate at
VHF when the tube is connected as an amplifier if the grid circuit looks
like a parallel tank circuit at VHF.   (In this case a 3" wire going to the
tuning cap ... 'parallel lines' tuned at the far end for VHF.)   However you
rarely see an HF oscillator pull this stunt because the negative grid bias
from the oscillation won't let the VHF oscillation keep going and there's
generally not enough time during the 'on' pulses of the tube for it to
start.  This circuit was an exception.   In effect the stage was
superregenerating, that is, the VHF oscillation was being quenched by the LO
frequency.   The roaring was the tube noise amplified by this action which
was wide enough bandwidth to cover the 1.7 mcs IF.

WW II radar jammers used amplified tube noise as modulation to transmit
signals that were megacycles wide.   I bet not too many people would have
tried using a broadband noise jammer as a receiver LO!

Ideally grid and plate leads in receiver RF/IF circuits are short enough
that hi-Q spurious resonances don't occur at frequencies at which the tubes
have substantial gain.   However that requirement is almost impossible to
meet in a receiver with plug-in coils when you factor in shielding, access,
the need for space around the oscillator coil to preserve Q and minimize
capacitive effects, and heat transmission considerations with the mechanical
requirements of the tuning cap and dial.   Too much real estate is needed
and there are too many conflicting 'zoning' requirements.

Next I tackled the 20 cps variation of oscillator frequency with AGC action.
While tinkering with circuit values to reduce sensitivity to plate voltage
changes was appealing, it didn't take long to realize this answer would only
be right on a single band.  (Transit time is part of what's being affected
...)  So, I dug a couple of 5651 voltage reference gas tubes out of the
archives and added another socket.   One tube turned out to be end-of-life,
so useful only for EOL testing (striking voltage goes up ...) but the other
was new.   Regulating both the plate and screen voltages on the 12BZ6
oscillator reduced the voltage change with full-range AGC action to ~1 volt
and the frequency shift to around 3 cps.

I had wound a temporary oscillator coil to shake out issues there; the next
job was doing a proper one.   This was a bigger chore than it should have
been because I had forgotten that I had completely rebuilt the receiver (new
chassis with revised tube layout) since calibrating the set with the
temporary coil.   So when I plugged in the new coil (which I thought was
identical L), the calibration was way off at the intermediate points on the
dial.

A couple of hours of head scratching later, I remembered the rebuilding AND
the fact that this setup makes synchronizing of the tuning cap to the dial
mechanism, critical.

(Remember that I generally make errors in filament wiring at least a couple
of times per project ... forgetting something like this is par for the
course!)

The Eddystone 898 and ball bearing-silver plated brass-soldered ceramic
tuning cap came as a pair from a very rough G3RKK receiver acquired several
years ago.  This is a UK 'Radio Communications Handbook' design,
contemporary with the W6TC sets but using a bandswitching front end.   The
front ends were sold as assembled units by the UK 'Electroniques' firm and
the dial was part of that package, already calibrated for (US)
160-80-40-20-10.   Thus I had a first quality capacitor that with the proper
coil and other parts should require only trimming to match a decent
pre-calibrated dial.

That wasn't quite as simple as it seemed, however, because in an effort to
use as much as possible of this excellent dial, the tuning capacitor is
rotated through more than the usual fraction of its range to cover each
band.   As a result, end effects are substantial.

At the low capacitance end, the 'open' end of the rotor starts to approach
the stator, so the rate of decrease of capacitance slows.   And at the high
capacitance end, the reverse is true -- the 'closed' end is approaching the
edge of the stator so the rate of increase slows -- although this effect is
less pronounced.  

The result is that while you can correct the high and low ends of the dial
by tweeking the trimmer capacitor and the coil and get a match somewhere
near the middle with a padder cap (effectively in series with the tuning
cap), the high frequency end can have a severe curvature one way or the
other if the rotor is even slightly off the correct position relative to the
dial mechanism.   Like -- errors at the other 100 kcs points in the ballpark
of a kc or two but 3900 is off by 20 kcs?   And 3800 by 10 kcs?

With great care in positioning the rotor it's possible to bring the errors
at all the 100 kcs points to under 1 kc.   That's as close as you can read
the dial and in fact less than the errors in the calibration of this unit --
if you look closely you can see that a few points are out of place by a
couple of kcs!  The calibrated dial is very pretty and accurate enough for
finding a net or QSO but not suitable for use as a frequency meter!

You'd think that the problem of tracking the various bands would be
simplified by looking at the original parts values.  Unfortunately the Radio
Communications Handbook I have doesn't show those values -- it assumes use
of the manufactured front end.   I do have the front end itself, but the
thing is a mess; even figuring out which coil is for which band isn't
trivial.   

(Looks like someone may have tried to convert a band for CB use or something
like that -- lots of loose wires, replaced wires with 'whatever' was at
hand, bare, DSSC, a couple of broken coils -- plus most caps are TINY and
located down inside a 2" deep chassis under the bandswitch and coils.)

There is some roughness on very strong SSB signals that goes away if you
crank the AGC threshold (RF/IF gain) control way back.  That's most likely
inadequate BFO injection, so I will look at that in the next day or two.
I'll also clean up the most recent oscillator wiring changes, and add a bit
of temperature compensation.

Ideally the chassis and each oscillator coil are independently compensated
so you can change a cold coil into a hot set and have minimum drift but I'm
afraid I'm not serious enough to get there.   Just tweaking the padder cap
inside the coil to get a three point match to the dial is a chore and since
temp compensation requires a final permanent assembly (no coil sitting loose
on the octal plug!), per-coil compensation would be a very tough job.

However in redoing the 80M coil I added one turn and spaced the winding a
bit.  With plastic forms (PVC pipe in this case) that makes the coil
somewhat self-compensating.   And the drift in the second minute -- after
the tube structure is nearly stabilized -- is now upward by a few hundred
cycles, so this lazy man's approach is helpful.   In the fourth minute and
after, the drift turns downward as is usual for uncompensated oscillators.
The total warm up drift (maximum freq. minus minimum) is now about 1 kc.

One point that's often missed in building stable oscillators: Self-heating
of tank circuit parts can be important, even at receiver LO power levels.
Start by operating the oscillator at the lowest possible power level, though
often that conflicts with the requirement to couple output as loosely as
possible.    Then use the physically largest caps you can find, orient them
for good cooling, and use two or more in parallel whenever possible.   Wind
the coil tightly with the heaviest wire practical and space turns slightly
if possible.  

This applies only to parts that are in the tank circuit, not to those
connecting it to other circuitry.  Typically this would be the tuning cap, a
parallel trimmer and any fixed caps in parallel, plus the padder cap that is
in series with the tuning cap.   (The Clapp and Vackar circuits have a
slightly different list of high current caps.)  And of course the coil
itself.   Getting high Q with fine wire and a ferrite core isn't as good as
getting it with heavy wire in solenoid form.

Also the advice to use very heavy wire hooking up the oscillator is not
always right: Heavy wire connected to a tube socket is a pipe for heat; with
a digital thermometer you can watch the temp rise flow out from the socket
to your tank circuit parts.   When fitting out a bomber, use #10 but for a
ham set use the smallest wire that will keep its place under the roughest
expected handling. 

Vibration is also an issue: A set with an integral loudspeaker will need
stiffer oscillator construction.   Loudspeakers should be as far as possible
from HF oscillators, use a heavier than usual panel, put heavy parts near
the speaker, and consider bracing the panel to the chassis in the vicinity
of the loudspeaker to eliminate mechanical resonance problems.

My digital thermometer shows the side of the coil nearest the center of the
set to be a couple of degrees warmer than the other side after half an hour
or so.   This could be either due to air flow -- the hottest part is the
117N7 on the far side of the set so air would tend to be sucked past the
coil in that direction -- or radiation from the 1st IF tube, located about
3-1/2" away on the warmer side.   Further investigation will follow.

I notice that the darn very slight warble is back.  That's gotta be 60 cps
getting into some oscillator -- most likely the LO -- but the effect is so
slight (and it comes and goes) so it's not easy to work on.   I should check
the bypassing of the cathode to chassis ground (cold cathode Colpitts
circuit) and (probably) move that filament to the grounded end of the string
-- It is #4 now and #1 (plate detector) got its problem taken care of in
another way.  I guess the warble is the priority project; an SSB receiver
cannot be satisfactory without rock solid oscillators.

Speaking of rocks, my 3500 kcs band edge marker crystal is a kc or two high;
I will check the shunt capacitance.   Of course it is about 70 years old
(has Signal Corps part number and marked for BC-1306) so this may be the
crystal itself.   

I'll probably do a 20M oscillator coil next, just to see how that goes.  I
won't be able to move the rotor relative to the dial for that one but
hopefully a two point match will be good enough.  The band is of course much
narrower percentagewise which should make it easier.

Anyway, it's a fun project.

Walt 
KJ4KV


From daileyservices at qwest.net  Sun Aug 14 14:28:01 2011
From: daileyservices at qwest.net (TC Dailey)
Date: Sun, 14 Aug 2011 12:28:01 -0600
Subject: [HBR] The long, SLOW HBR project
References: <CA6D6BCA.6215%waltah@earthlink.net>
Message-ID: <144C99C903EA42C6B12518B52DEC2CAD@w0eaj>

Very nicely written, Walt.

Tom - EAJ

From radioconnection at gmail.com  Sun Aug 14 14:34:58 2011
From: radioconnection at gmail.com (Peter Bertini)
Date: Sun, 14 Aug 2011 14:34:58 -0400
Subject: [HBR] The long, SLOW HBR project
In-Reply-To: <144C99C903EA42C6B12518B52DEC2CAD@w0eaj>
References: <CA6D6BCA.6215%waltah@earthlink.net>
	<144C99C903EA42C6B12518B52DEC2CAD@w0eaj>
Message-ID: <CA+uDY2R0BhNCF3Tm2x3Who8qBNTomQUK=kTfZMj8Y+Emz9GAmQ@mail.gmail.com>

Thanks Walt. This reminds of what ham radio was back in the sixties... very
informative and educational, and fun to
read. Thanks for sharing.

Pete k1zjh

On Sun, Aug 14, 2011 at 2:28 PM, TC Dailey <daileyservices at qwest.net> wrote:

> Very nicely written, Walt.
>
> Tom - EAJ
>  ______________________________________________________________
> HBR mailing list
> Home: http://mailman.qth.net/mailman/listinfo/hbr
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:HBR at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>

From waltah at earthlink.net  Sun Aug 14 16:09:46 2011
From: waltah at earthlink.net (Walt Hutchens)
Date: Sun, 14 Aug 2011 16:09:46 -0400
Subject: [HBR] The long, SLOW HBR project
In-Reply-To: <CA+uDY2R0BhNCF3Tm2x3Who8qBNTomQUK=kTfZMj8Y+Emz9GAmQ@mail.gmail.com>
Message-ID: <CA6DA3CA.623F%waltah@earthlink.net>

Peter said:

> Thanks Walt. This reminds of what ham radio was back in the sixties...

This isn't the sixties?   No WONDER Sharyn says I'm out of date.

I guess there aren't gonna be any more Liz Taylor or Marilyn Monroe movies,
are there?

The warble turns out to be a real challenge.

Things it seems NOT to be:

1.  60 cps getting into an oscillator -- at least not in any obvious way.
The reason it appeared to come and go is that it only appears on a beat note
when that beat is close to certain frequencies.   In between frequencies are
perfectly pure.  Also the frequency seems to be lower than 60 cps.

I think this makes it likely to be some sort of feedback effect.

2. Mechanical, resulting from the use of a panel mounted speaker.
Disconnecting the panel speaker and using one sitting on the table makes no
change.

3. Mechanical in some other way.  I spend several minutes touring the set
with a plastic stick touching various parts and wires and nothing makes any
difference.   

4. In the audio section.   Feeding the volume control with an audio
oscillator shows no such effect at any frequency.

It does seem, however, that the audio section could be a co-conspirator.
What stages KNOW about a beat note?   And the audio section is where the
power is.   

On the other hand, the volume control doesn't seem to have much effect.  If
the audio power stage was (say) feeding back through the plate voltage you'd
expect the effect to disappear at low volume.

There is a potential feedback path from the audio detector to the AGC
detector because they both use the same negative supply.  Hummm ...

5. An obvious weakness in HV supply/filtering.    I toured this area with
another large filter cap, shunting each in turn.   No change.

6.  Involving the AGC circuit.  A substantial increase in the AGC time
constant made no difference.

Time, I think, to break out the 'scope and look at all the voltages.

> very informative and educational, and fun to read. Thanks for sharing.

Thank YOU.  More to come.

Walt
KJ4KV









very
> informative and educational, and fun to
> read. Thanks for sharing.


From waltah at earthlink.net  Sun Aug 14 20:19:31 2011
From: waltah at earthlink.net (Walt Hutchens)
Date: Sun, 14 Aug 2011 20:19:31 -0400
Subject: [HBR] The long, SLOW HBR project
In-Reply-To: <CA6DA3CA.623F%waltah@earthlink.net>
Message-ID: <CA6DDE53.6255%waltah@earthlink.net>

I said:

> The warble turns out to be a real challenge.

Yeah ... and sometimes some or all of the tubes don't light up because the
filament circuit is wired wrong.

After poking around with the scope and finding nothing of interest I did
what I probably should have tried first: Dragged out the signal generator to
localize the problem to a stage.

Coupling a 1700 kcs signal to the plate of the mixer was fine.   Coupling a
3500 kcs signal in the same place and tuning the receiver accordingly was
NOT fine -- same old warble.   That fingered the oscillator, so I replaced
the tube.  Problem gone.

Heater to cathode leakage.  Line operated sets do put more stress on H-K
insulation but the tubes designed for series string operation are supposed
to be able to handle it.   This one, wasn't, and I've seen the problem a
couple of times before.  I don't know why the symptoms were so odd.

The bad tube was branded Alan B. Dumont; I've no idea who actually made it.

I should still move this tube farther down the string (toward the neutral
side of the line, which is where the cathode returns) to minimize the chance
of future problems.  The local oscillator is now probably the most sensitive
stage to this sort of failure.

All of the last few years of vacuum tube TV sets and the great majority of
AM/FM tube radios after 1950 were series filament/power line HV.  A 9-tube
ham band receiver is by no means pushing the state of that art.   But of
course those designers knew what they were doing and the tubes were brand
new in those years.

On this subject as on many others the circuit diagrams in the back of the
RCA Receiving Tube Manual are invaluable.   They show AM/FM series string
sets with the oscillator and mixer stages in mid-string and cathodes that
are 'hot' for RF yet -- something I wouldn't try.   Both the BW and color TV
sets have the front end tubes at the grounded end of the string but they too
have 'hot' cathodes.

Of course all of this equipment is designed for use with MUCH stronger
signals than a ham receiver, so some issues are less difficult.

The receiver sounds fine now, so on to less challenging challenges -- I
hope.  I guess I'll tidy up the local oscillator area first.

Walt
KJ4KV  




From ianmwilson73 at gmail.com  Mon Aug 15 11:14:46 2011
From: ianmwilson73 at gmail.com (Ian Wilson)
Date: Mon, 15 Aug 2011 08:14:46 -0700
Subject: [HBR] Just in case, before parting out..
Message-ID: <CAEz8jcRCXfXoq1XxNVy6AWVOEE271Bq+1uJjsgWzgQMTZ3vRSw@mail.gmail.com>

I am just about to part out the receiver chassis from an early GE FM mobile
rig.
The chassis is about 17" x 4" x 6" high (most of that height is due to long
tall
IF cans). The chassis is an 'L' not a 'U'.

Downstream of the VHF front end, there are two ~9MHz IF stages. Following
this
is a 6U8 crystal-controlled converter to a lower IF (perhaps 455kHz). There
are three 2nd IF
amplifier stages. Each has two IF cans (presumably to achieve FM bandwidth
needs).
There are limiter/disciminator stages followed by a small audio chain to a
6AQ5 with small
speaker transformer.

This might be kinda interesting if you add a 9MHz homebrew xtal filter ahead
of the
1st IF, and rip out the VHF stuff ahead of it.

If I have time I will do a couple of experiments to determine the
approximate IF frequencies.

The original channel crystals are gone but the 7490kHz xtal in the 2nd mixer
is present.
No tubes are present. Most of the original tubes were 6BH6's.

Just in case anyone wants this for say $7.50 plus shipping, please let me
know off-list.

73, ian K3IMW

From ianmwilson73 at gmail.com  Mon Aug 15 11:53:48 2011
From: ianmwilson73 at gmail.com (Ian Wilson)
Date: Mon, 15 Aug 2011 08:53:48 -0700
Subject: [HBR] Just in case, before parting out..
In-Reply-To: <CAEz8jcRCXfXoq1XxNVy6AWVOEE271Bq+1uJjsgWzgQMTZ3vRSw@mail.gmail.com>
References: <CAEz8jcRCXfXoq1XxNVy6AWVOEE271Bq+1uJjsgWzgQMTZ3vRSw@mail.gmail.com>
Message-ID: <CAEz8jcQcYLAVg9KxKmNNF7MQLcEwFPd5K3x0YYqjZ7dvV0tMLA@mail.gmail.com>

The 2nd IF is centered on 460kHz with a (double-tuned) bandwidth of about
40kHz.
It appears that the 'pairs' of IF cans must actually be joined in some way
between
units, as there are only 3 wires (input, B+, output) coming from the
undersides. So
that makes the 1st IF around 8MHz.

73, ian K3IMW

From smithab11 at comcast.net  Thu Aug 18 19:35:50 2011
From: smithab11 at comcast.net (B Smith)
Date: Thu, 18 Aug 2011 19:35:50 -0400
Subject: [HBR] WEB SITE
In-Reply-To: <1313686865.64399.YahooMailRC@web81005.mail.mud.yahoo.com>
References: <1313686865.64399.YahooMailRC@web81005.mail.mud.yahoo.com>
Message-ID: <EA1D3B53CA524CC28B9ECC02C8199B15@Dell560>

Looks like Charles Byers has updated his web site. Highly recommended for
his Chassis Kits, excellent for HBR receivers. 
73
breck k4che



 
TO ACCESS MY WEB SITE - www.k3iwk.net


THANKS
Charles Byers K3IWK
Byers Chassis Kits

From bignick at execpc.com  Fri Aug 19 22:23:29 2011
From: bignick at execpc.com (bignick at execpc.com)
Date: Fri, 19 Aug 2011 22:23:29 -0400 (EDT)
Subject: [HBR] HBR-16 Sighting
Message-ID: <63457.67.53.185.165.1313807009.squirrel@newmail.core.com>



For those who may be interested ..

http://www.ebay.com/itm/HBR-16-Receiver-1959-Homebrew-radio-QST-/140594380375?pt=LH_DefaultDomain_0&hash=item20bc13fe57

73

--KC9KEP

From wrcromwell at gmail.com  Sat Aug 20 08:33:19 2011
From: wrcromwell at gmail.com (Bill Cromwell)
Date: Sat, 20 Aug 2011 08:33:19 -0400
Subject: [HBR] HBR-16 Sighting
In-Reply-To: <63457.67.53.185.165.1313807009.squirrel@newmail.core.com>
References: <63457.67.53.185.165.1313807009.squirrel@newmail.core.com>
Message-ID: <1313843599.2605.14.camel@lancelot>

On Fri, 2011-08-19 at 22:23 -0400, bignick at execpc.com wrote:
> 
> For those who may be interested ..
> 
> http://www.ebay.com/itm/HBR-16-Receiver-1959-Homebrew-radio-QST-/140594380375?pt=LH_DefaultDomain_0&hash=item20bc13fe57
> 
> 73
> 
> --KC9KEP

Somebody going to be looking for a bucket full of coil forms.

73,

Bill  KU8H


From windy10605 at juno.com  Sat Aug 20 10:57:18 2011
From: windy10605 at juno.com (Kees & Sandy)
Date: Sat, 20 Aug 2011 14:57:18 GMT
Subject: [HBR] HBR-16 Sighting
Message-ID: <20110820.095718.29763.0@webmail01.dca.untd.com>

I never cease to be amazed at how many of those 50 year old homebrew receivers continue to show up and that they were never stripped for parts to build other projects. Shows a lot of pride in the resulting receiver.
73 Kees K5BCQ 

---------- Original Message ----------
From: bignick at execpc.com
To: "HBR Receiver List" <hbr at mailman.qth.net>
Subject: [HBR] HBR-16 Sighting
Date: Fri, 19 Aug 2011 22:23:29 -0400 (EDT)




For those who may be interested ..

http://www.ebay.com/itm/HBR-16-Receiver-1959-Homebrew-radio-QST-/140594380375?pt=LH_DefaultDomain_0&hash=item20bc13fe57

73

--KC9KEP
______________________________________________________________
HBR mailing list
Home: http://mailman.qth.net/mailman/listinfo/hbr
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:HBR at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html


From daileyservices at qwest.net  Sat Aug 20 11:13:06 2011
From: daileyservices at qwest.net (TC Dailey)
Date: Sat, 20 Aug 2011 09:13:06 -0600
Subject: [HBR] They survive
References: <20110820.095718.29763.0@webmail01.dca.untd.com>
Message-ID: <AE89F5CD27884951B84B1BE9B50DDC69@w0eaj>

My HBR-11 showed up at an estate sale, missing a tube and with only 40m 
coils - a year after it was given to me, I not only discovered WHAT it was & 
got it going, but as it turned out, the guy who gave it to me, found out he 
WORKED WITH the guy who originally built it in 1964 - the builder STILL had 
the extra coils for 20m, 15m, and 2-of-the-3 for 75m... IN the original 
ALLIED RADIO box he'd gotten the parts IN.  Yep - they just go on and on. 
(OF COURSE I kept the box!)

Tom - W0EAJ 


From windy10605 at juno.com  Sat Aug 20 11:23:49 2011
From: windy10605 at juno.com (Kees & Sandy)
Date: Sat, 20 Aug 2011 15:23:49 GMT
Subject: [HBR] They survive
Message-ID: <20110820.102349.29763.5@webmail01.dca.untd.com>

Great story !!
73 Kees K5BCQ

---------- Original Message ----------
From: "TC Dailey" <daileyservices at qwest.net>
To: "HBR Receiver List" <hbr at mailman.qth.net>
Subject: [HBR] They survive
Date: Sat, 20 Aug 2011 09:13:06 -0600

My HBR-11 showed up at an estate sale, missing a tube and with only 40m 
coils - a year after it was given to me, I not only discovered WHAT it was & 
got it going, but as it turned out, the guy who gave it to me, found out he 
WORKED WITH the guy who originally built it in 1964 - the builder STILL had 
the extra coils for 20m, 15m, and 2-of-the-3 for 75m... IN the original 
ALLIED RADIO box he'd gotten the parts IN.  Yep - they just go on and on. 
(OF COURSE I kept the box!)

Tom - W0EAJ 

______________________________________________________________
HBR mailing list
Home: http://mailman.qth.net/mailman/listinfo/hbr
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:HBR at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html


From waltah at earthlink.net  Sat Aug 20 11:55:11 2011
From: waltah at earthlink.net (Walt Hutchens)
Date: Sat, 20 Aug 2011 11:55:11 -0400
Subject: [HBR] HBR-16 Sighting
In-Reply-To: <20110820.095718.29763.0@webmail01.dca.untd.com>
Message-ID: <CA75511F.6A1D%waltah@earthlink.net>

Kees said:

> I never cease to be amazed at how many of those 50 year old homebrew receivers
> continue to show up and that they were never stripped for parts to build other
> projects. Shows a lot of pride in the resulting receiver.

One of the reasons this list and this area of ham radio are of such great
interest.

One thing I've wondered about: Has anyone written about W6TC himself?  He
not only had a remarkable vision, he had the talent and energy to carry it
to success.   I don't think it's too much to say that if he had been a top
player at any of the major U.S. ham equipment companies in the 50's-60's,
the history of our hobby might have been different.

What about, for example, Heathkit?

The best ham radios that could have been, were never built.   The W6TC HBRs
were among the farthest flags up the mountain of what WAS done.

What is known about the man himself?

Walt
KJ4KV


From johnmb at nc.rr.com  Sat Aug 20 13:46:52 2011
From: johnmb at nc.rr.com (john)
Date: Sat, 20 Aug 2011 13:46:52 -0400
Subject: [HBR] HBR-16 Sighting
In-Reply-To: <20110820.095718.29763.0@webmail01.dca.untd.com>
References: <20110820.095718.29763.0@webmail01.dca.untd.com>
Message-ID: <6.2.1.2.2.20110820134539.03886eb0@pop-server.nc.rr.com>

My guess is that part of the high survival rate is

1) People spent a lot of time building these things, therefore there was a 
strong emotional attachment.

--and--

2) THEY WORKED!

(I HATE staring at project I never got to work...usually if I give up, it's 
out the door it goes!)

John K5MO



At 10:57 AM 8/20/2011, you wrote:
>I never cease to be amazed at how many of those 50 year old homebrew 
>receivers continue to show up and that they were never stripped for parts 
>to build other projects. Shows a lot of pride in the resulting receiver.
>73 Kees K5BCQ
>
>---------- Original Message ----------
>From: bignick at execpc.com
>To: "HBR Receiver List" <hbr at mailman.qth.net>
>Subject: [HBR] HBR-16 Sighting
>Date: Fri, 19 Aug 2011 22:23:29 -0400 (EDT)
>
>
>
>
>For those who may be interested ..
>
>http://www.ebay.com/itm/HBR-16-Receiver-1959-Homebrew-radio-QST-/140594380375?pt=LH_DefaultDomain_0&hash=item20bc13fe57
>
>73
>
>--KC9KEP
>______________________________________________________________
>HBR mailing list
>Home: http://mailman.qth.net/mailman/listinfo/hbr
>Help: http://mailman.qth.net/mmfaq.htm
>Post: mailto:HBR at mailman.qth.net
>
>This list hosted by: http://www.qsl.net
>Please help support this email list: http://www.qsl.net/donate.html
>
>______________________________________________________________
>HBR mailing list
>Home: http://mailman.qth.net/mailman/listinfo/hbr
>Help: http://mailman.qth.net/mmfaq.htm
>Post: mailto:HBR at mailman.qth.net
>
>This list hosted by: http://www.qsl.net
>Please help support this email list: http://www.qsl.net/donate.html


From leecraner at aol.com  Sat Aug 20 14:12:50 2011
From: leecraner at aol.com (leecraner at aol.com)
Date: Sat, 20 Aug 2011 14:12:50 -0400 (EDT)
Subject: [HBR] HBR-16 Sighting
In-Reply-To: <CA75511F.6A1D%waltah@earthlink.net>
References: <CA75511F.6A1D%waltah@earthlink.net>
Message-ID: <8CE2D7BE8133B5F-176C-137B9@webmail-d032.sysops.aol.com>


Walt:

One gets a good insight to Ted Crosby, W6TC, in Jay Helms' W6HHT ebook, "Recollections of a Radio Receiver."  Jay's website is www.w6hht.com.

73
Lee WB6SSW






-----Original Message-----
From: Walt Hutchens <waltah at earthlink.net>
To: HBR Receiver List <hbr at mailman.qth.net>
Sent: Sat, Aug 20, 2011 3:56 pm
Subject: Re: [HBR] HBR-16 Sighting


Kees said:
> I never cease to be amazed at how many of those 50 year old homebrew receivers
 continue to show up and that they were never stripped for parts to build other
 projects. Shows a lot of pride in the resulting receiver.
One of the reasons this list and this area of ham radio are of such great
nterest.
One thing I've wondered about: Has anyone written about W6TC himself?  He
ot only had a remarkable vision, he had the talent and energy to carry it
o success.   I don't think it's too much to say that if he had been a top
layer at any of the major U.S. ham equipment companies in the 50's-60's,
he history of our hobby might have been different.
What about, for example, Heathkit?
The best ham radios that could have been, were never built.   The W6TC HBRs
ere among the farthest flags up the mountain of what WAS done.
What is known about the man himself?
Walt
J4KV
______________________________________________________________
BR mailing list
ome: http://mailman.qth.net/mailman/listinfo/hbr
elp: http://mailman.qth.net/mmfaq.htm
ost: mailto:HBR at mailman.qth.net
This list hosted by: http://www.qsl.net
lease help support this email list: http://www.qsl.net/donate.html


From whitebear1122 at comcast.net  Sat Aug 20 14:24:26 2011
From: whitebear1122 at comcast.net (whitebear1122 at comcast.net)
Date: Sat, 20 Aug 2011 18:24:26 +0000 (UTC)
Subject: [HBR] HBR-16 Sighting
In-Reply-To: <20110820.095718.29763.0@webmail01.dca.untd.com>
Message-ID: <187419513.506150.1313864666068.JavaMail.root@sz0139a.emeryville.ca.mail.comcast.net>

Kees wrote: "......and that they were never stripped for parts to build other projects. Shows a lot of pride in the resulting receiver." 

How true! I think I told the story here earlier in the summer when a local OT'er gave me his HBR-17. A mutual friend had been telling me about the old gent who built his own equipment. So one day the friend stops by and says lets go visit the good doctor. We did. I think I was being "interviewed" by the doctor to find out if I was worthy I guess. After the end of the discussion the OT tells me he'd like to give me his homemade receiver that he built in the early 60's. Turns out it is an HBR-17,(the HBR-16 that was hotrodded by Bill McKay W7QBR with the Q-multiplier, plus LSB,USB,CW selector, plus other fine tuning. The OT said it was as hot as any receiver today. I figured he might be embellishing the performance just a tad. hi hi 

It came with a full set of coils from 10m - 80m. The coil box was handwritten with words like "Precious! Coils for my homemade receiver, irreplaceable".He had stopped using it around 1973 and set it on the floor next to his operating desk, and there it sat until I moved all the junk off of it and pulled it out. 

It is very dusty and all knobs have some sort of fuzz or white growth on the top 180 degrees of the knob. The undersides are clean. While the shack has mega evidence of mice infestation, luckily there wasn't a single turd on the receiver. He also gave me all of the original design details including Bill McKays chassis layout and schematic, plus Ed Kents original offering of HBR notes. The receiver came with a homemade speaker cabinet has well, nicely done. 

I brought it home and brought it up slowly on a variac to make sure the HV caps were charging up and not shoring. It was still coiled up for 40m as it was when it was last used in the early 70's. 40m came to life and I was greeted with nice sounding cw signals. Wow the OT wasn't exaggerating at all, it was a hot performer. Signals that popped out of the low noise, great cw and SSB, stable. I popped in the 20m coils and listened around there. 20m was abuzz with some CW contest and the HBR held it's own as I picked my way through the bedlam. He was right, it was an amazing receiver. I have a brief youtube.com video of it, look for w0wb hbr-17 on youtube.com. 

So these guys like W7QBR, W6TC, W0WB were building quality ham receivers back in the 60's, no junk, no compromised radios, no toys, but communication quality receivers.. I think most hams just don't realize how good those receivers are (not were but ARE). 

Summer is a slow radio time for me as I do most of my radio'n in the Fall, Winter, and Spring. Till, I've collected nearly all the components now to build my own HBR receiver starting sometime this Fall. While I am planning to build an HBR-11, I must admit that the OT's HBR-17 has made me think about building that version instead based on its fabulous performance. 

I just took delivery yesterday of a superb radio cabinet and blank front panel and NOS Eddystone dial from a list member here. I haven't opened the box yet. I won't mention names yet until I get the ok. He had been saving it for his own HBR and decided that he may never get around to building it, so he gave it to me with the promise that I would build an HBR with it. Gads I can hardly wait to get started on my own HBR-11 or 17 this Fall, once I start and finish the walkout basement and shack remodeling project that my wife is asking for. hi hi 

I am buying passive parts including caps and resistors for two receivers, this one and a future end game HBR-13C. 

So yes there is alot of pride around those old HBR's and new HBR's. 

73, Scott WA9WFA in Saint Paul MN 

From daileyservices at qwest.net  Sat Aug 20 15:42:32 2011
From: daileyservices at qwest.net (TC Dailey)
Date: Sat, 20 Aug 2011 13:42:32 -0600
Subject: [HBR] HBR's being "as good"
References: <187419513.506150.1313864666068.JavaMail.root@sz0139a.emeryville.ca.mail.comcast.net>
Message-ID: <27E63E559DC54D508E38403852DA232F@w0eaj>

Neat story, Scott... I did enjoy it.  After I got my HBR-11 going, I did a 
three-time realignment on it (just to make it as good as I could get it), 
and it provides READABLE CW at .045uv on 75m - my 756 PROII can do it, but 
it takes a LOT of "fiddling around" to make it happen.

... besides, guys - Face It - we love the darned things because they produce 
such a great SMELL when they're warm!

Tom 


From waltah at earthlink.net  Tue Aug 23 15:07:13 2011
From: waltah at earthlink.net (Walt Hutchens)
Date: Tue, 23 Aug 2011 15:07:13 -0400
Subject: [HBR] The long, SLOW HBR project
In-Reply-To: <CA6DDE53.6255%waltah@earthlink.net>
Message-ID: <CA7972A1.6CB3%waltah@earthlink.net>

Subtitle: This wasn't PLANNED as a learning experience ...

> I guess I'll tidy up the local oscillator area first.

Not too much to that ... just a couple of tacked on parts needing more
permanent mounting.  But the warm-up drift -- up a couple of hundred cps
(since the slightly space wound LO coil)  then downward 800 cps or so below
the starting point (max to min = 1 kcs) -- seemed just a bit high,
especially when translated to higher bands.

Changing the one remaining mica cap for an NPO ceramic and putting a
tinplate shield over the tuning cap to reflect heat from the nearby mixer
tube -- I should have put a bit more space in there when laying out the
chassis -- got the 1 kcs max-to-min down to 600 cps or so.

But ... where was THAT?   Nothing in the tank circuit area increased in temp
by over 10 degrees F or so, the coil had a negative coefficient, and the
(shielded) high quality cap didn't seem likely to contribute much.   Plus
all this testing was done at 4 Mcs, close to minimum capacitance.

I started measuring temps here and there as the set warmed up and after a
couple of days of intermittent testing and staring, it hit me:  The top
surface of the chassis is constrained on all four edges.  It's aluminum
(high temp coefficient) and where's it going to go as it expands?  In theory
it could either bulge upward or downward, but the way it was bent, I
expected it to bulge up.

The tuning cap is mounted on the 4"x5" surface of the top of a minibox,
fastened on its side on the right edge of the main chassis.  When I did
that, I thought "plenty stiff."   Well, it IS stiff enough to avoid backlash
due to chassis flexure when the dial is turned (the first thing you worry
about), but if you assume the top surface of the chassis bulges a bit with
temp. increase, then the minibox would be twisted, causing the tuning cap
frame to rotate in the direction of increasing capacitance while the rotor
was held in place by the dial.

There's a link to a picture showing the tuning cap mounting, below.

This effect is, of course, MUCH too small to be visible.   But (say) 500 cps
when half a revolution is 500 kcs, is 1/2000 of a revolution of the tuning
cap ... that wouldn't be enough to see.

When I pressed on the various chassis parts in the corresponding directions
I had no trouble reproducing the amount of frequency change.   And when --
after a full warm up -- I dropped a small lump of ice at what I judged to be
the hot spot on the chassis, I was rewarded with a 50 cps increase of
frequency over the next minute or so, even though that location is several
inches from the oscillator parts.

Good enough for me.   I spent a couple of hours making a vertical plate to
go inside the chassis under the front of the minibox, to brace it to the
side of the chassis.  Because the lower lip of the chassis is folded inward
(and the corners are welded) such a brace should greatly reduce bulging
along its top edge and thus reduce rotation of the capacitor frame.   Of
course this concentrates the bulge in the left 2/3 of the chassis surface,
but for an effect too small to be detected except by oscillator drift, that
should be okay.  

For good measure I put small triangular plates in the lower corners of the
chassis to lock the right bottom lip to the front and rear lips.

Warm up drift was reduced to ~400 cps, max to min.

There's a reason all those military sets are made from 1/8" or thicker
material AND folded and braced to be extremely stiff.    And for those
wondering why anyone would build on a steel chassis, here's a reason:  Steel
has a lower coefficient of expansion AND is considerably stiffer.

I'll stick with aluminum, but it's not a perfect material.   However steel
might be a good choice for a VFO.

The next step was reducing the heating of the chassis by drilling six 1/4"
holes around the 117N7 -- at more than 10 watts (out of about 35)  the
single greatest source of heat, plus it is almost directly lined up with the
front edge of the minibox.  This reduced warm up drift to 260 cps (max to
min) over half an hour.

Hey, if six little holes is good, one great big hole must be better, right?
So I knocked out a 2" octagon around the 117N7 and mounted a 2-1/4" square
plate with the tube socket about 1/4" below the chassis surface; air pulled
by the high temperature of the tube can come up between the plate and the
chassis, thus cooling both.

That reduced the drift to ... er, wait ... it INCREASED  it to over 500 cps.

???

Another day of unhappy head scratching clarified the issue: While the large
hole and sub-mounted plate/socket no doubt reduced the temperature rise
somewhat, the way I did it greatly increased the stiffness of that (hottest)
part of the chassis, thus INCREASING the bulging of the rest and the
resulting drift.   Stiffening oscillator area = GOOD, stiffening elsewhere =
BAD!   

Perhaps the answer was to mount the new plate and socket less rigidly.  One
trip to Lowes later, I had four 1/4" nylon bushings with nylon 6-32 screws
and nuts to match and a few minutes work with needlenose and screwdriver
replaced the steel and brass hardware I had originally installed.   THAT did
the trick: Max-to-min drift was reduced to 153 cps.

Testing at 3.5 Mcs with the final set of changes the drift is about 500
max-to-min.    

'Max-to-min' is of course a fairly stringent standard.   Drift after 20 min.
warmup might better reflect ordinary use: Those numbers are 62 cps at 4 Mcs
and 153 cps at 3.5 Mcs, to a single measurement at least two hours after
starting, with the per-hour drift thereafter expected to be <50 cps.

There are pictures of the first chassis here:

https://picasaweb.google.com/105255380483660395824/WaltS2008Project

The 5th pic from the bottom is the clearest view of the tuning cap mounting.
The rotor of the cap turns CCW (as seen from the rear) to increase
frequency.  If you imagine the chassis bulging upward and rotating the front
of the minbox on which the cap is mounted CCW, you can see how downward
drift would occur. 

I started over with a new chassis perhaps a year ago, transferring most
stages with minimum change.  All the major parts are in the same places (and
the panel was reused) but several tubes and the IFTs got relocated for a
much cleaner signal flow and shorter leads.   I'll get new pictures up
within a few days.

Doing it again I'd rethink the stiffness/heat flow issues yet again.
Whether that would lead to significant change, I don't know: There are
already many other constraints on the layout.

Examples of constraints: The minibox shields the antenna coil from the mixer
and IF stages and keeps the heat of the oscillator tube off the oscillator
coil -- one piece of standard metalwork replacing two or three needing
custom fabrication.   Easy access to all coils is required. Since even
objects 8" away affect the frequency it is impossible to have too much
clearance around the oscillator coil.   The oscillator coil and BFO are best
placed near the front since both have front  panel controls.   The two
filter chokes and the BFO coil are conveniently mounted on the left chassis
side because the wiring of those stages is simple enough that the sockets
can be mounted under these three components.

Then there are the usual rules about trying to get the stages in a straight
line.   With one thing and another, this project is not too open to further
improvements in layout -- but that doesn't mean that they're impossible.

However, the lesson that the top of a chassis can change shape during warm
up and thus contribute substantially to drift is a useful one.

The idea is that air will enter the chassis from below.  For testing this
was done by raising the left and right edges on 1/4" strips.   When the set
gets a cabinet, I'll probably cut a 1" or larger hole in the rear of the
chassis.   Forced air into the chassis using a small computer fan might make
sense, although the DC power requirement may be an issue; I'll look at using
the cathode current of the 117N7 output stage.

Walt
KJ4KV








From garypewitt at centurytel.net  Tue Aug 23 15:55:38 2011
From: garypewitt at centurytel.net (Gary Pewitt)
Date: Tue, 23 Aug 2011 14:55:38 -0500
Subject: [HBR] The long, SLOW HBR project
In-Reply-To: <CA7972A1.6CB3%waltah@earthlink.net>
References: <CA7972A1.6CB3%waltah@earthlink.net>
Message-ID: <4E5405BA.6050707@centurytel.net>

Walt, I love these posts.  This is the true spirit of ham radio.  Try, 
test, tinker, think, retry, change, test and so on.  Way to go.
73  Gary  N9ZSV


On 8/23/2011 2:07 PM, Walt Hutchens wrote:
> Subtitle: This wasn't PLANNED as a learning experience ...
>
>    
> Big snip.
>
>
>    


-- 
Gary Pewitt   N9ZSV
1500 French Prairie Rd
Booneville, AR  72927


From ke9xq at charter.net  Tue Aug 23 18:49:59 2011
From: ke9xq at charter.net (William Wood)
Date: Tue, 23 Aug 2011 17:49:59 -0500
Subject: [HBR] someone wants that receiver : )
Message-ID: <D1BA09D4-D142-4000-8155-5DE6305019C2@charter.net>

Anyone here bidding on that HBR 17
I put a couple bids in there, but it got
expensive right away, and don't think
I can scrape up any more shekels at
the moment : )  305 is getting up there
73
Bill



If the grass is greener on the
other side of the fence, then
maybe you ain't watering
your own lawn...

Favorite Yahoo Groups...

http://groups.yahoo.com/group/OTR_and_Music/

http://groups.yahoo.com/group/Radio_Library/

And check out Tennessee Bill's site at:

http://otrshareandtrade.com/in.php?ID=12
and his personal site at:

http://TennesseeBillsOTR.com

Don't forget

http://www.archive.org/index.php

and one or two that maybe don't
want to be listed : )
And two dozen or more others
I won't tell you about unless you ask.


From Bobby at McKahans.com  Tue Aug 23 20:30:59 2011
From: Bobby at McKahans.com (Bobby McKahan K4VE)
Date: Tue, 23 Aug 2011 20:30:59 -0400
Subject: [HBR] someone wants that receiver : )
References: <D1BA09D4-D142-4000-8155-5DE6305019C2@charter.net>
Message-ID: <3512D574222249D994E6DC021D3DB812@pipesmoke>

You mean the HBR 16 on Ebay?

----- Original Message ----- 
From: "William Wood" <ke9xq at charter.net>
To: "HBR Receiver List" <hbr at mailman.qth.net>
Sent: Tuesday, August 23, 2011 6:49 PM
Subject: [HBR] someone wants that receiver : )


> Anyone here bidding on that HBR 17
> I put a couple bids in there, but it got
> expensive right away, and don't think
> I can scrape up any more shekels at
> the moment : )  305 is getting up there
> 73
> Bill
> 
> 
> 
> If the grass is greener on the
> other side of the fence, then
> maybe you ain't watering
> your own lawn...
> 
> Favorite Yahoo Groups...
> 
> http://groups.yahoo.com/group/OTR_and_Music/
> 
> http://groups.yahoo.com/group/Radio_Library/
> 
> And check out Tennessee Bill's site at:
> 
> http://otrshareandtrade.com/in.php?ID=12
> and his personal site at:
> 
> http://TennesseeBillsOTR.com
> 
> Don't forget
> 
> http://www.archive.org/index.php
> 
> and one or two that maybe don't
> want to be listed : )
> And two dozen or more others
> I won't tell you about unless you ask.
> 
> ______________________________________________________________
> HBR mailing list
> Home: http://mailman.qth.net/mailman/listinfo/hbr
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:HBR at mailman.qth.net
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> 
> 
> 
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 10.0.1392 / Virus Database: 1520/3853 - Release Date: 08/23/11
>

From ke9xq at charter.net  Tue Aug 23 21:56:27 2011
From: ke9xq at charter.net (William Wood)
Date: Tue, 23 Aug 2011 20:56:27 -0500
Subject: [HBR] someone wants that receiver : )
In-Reply-To: <3512D574222249D994E6DC021D3DB812@pipesmoke>
References: <D1BA09D4-D142-4000-8155-5DE6305019C2@charter.net>
	<3512D574222249D994E6DC021D3DB812@pipesmoke>
Message-ID: <313752A7-0389-4569-9BF2-241E7AA5B588@charter.net>

yup : )

On Aug 23, 2011, at 7:30 PM, Bobby McKahan K4VE wrote:

> You mean the HBR 16 on Ebay?
>
> ----- Original Message -----
> From: "William Wood" <ke9xq at charter.net>
> To: "HBR Receiver List" <hbr at mailman.qth.net>
> Sent: Tuesday, August 23, 2011 6:49 PM
> Subject: [HBR] someone wants that receiver : )
>
>
>> Anyone here bidding on that HBR 17
>> I put a couple bids in there, but it got
>> expensive right away, and don't think
>> I can scrape up any more shekels at
>> the moment : )  305 is getting up there
>> 73
>> Bill
>>
>>
>>
>> If the grass is greener on the
>> other side of the fence, then
>> maybe you ain't watering
>> your own lawn...
>>
>> Favorite Yahoo Groups...
>>
>> http://groups.yahoo.com/group/OTR_and_Music/
>>
>> http://groups.yahoo.com/group/Radio_Library/
>>
>> And check out Tennessee Bill's site at:
>>
>> http://otrshareandtrade.com/in.php?ID=12
>> and his personal site at:
>>
>> http://TennesseeBillsOTR.com
>>
>> Don't forget
>>
>> http://www.archive.org/index.php
>>
>> and one or two that maybe don't
>> want to be listed : )
>> And two dozen or more others
>> I won't tell you about unless you ask.
>>
>> ______________________________________________________________
>> HBR mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/hbr
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:HBR at mailman.qth.net
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>>
>>
>>
>> -----
>> No virus found in this message.
>> Checked by AVG - www.avg.com
>> Version: 10.0.1392 / Virus Database: 1520/3853 - Release Date:  
>> 08/23/11
>>
> ______________________________________________________________
> HBR mailing list
> Home: http://mailman.qth.net/mailman/listinfo/hbr
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:HBR at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html

If the grass is greener on the
other side of the fence, then
maybe you ain't watering
your own lawn...

Favorite Yahoo Groups...

http://groups.yahoo.com/group/OTR_and_Music/

http://groups.yahoo.com/group/Radio_Library/

And check out Tennessee Bill's site at:

http://otrshareandtrade.com/in.php?ID=12
and his personal site at:

http://TennesseeBillsOTR.com

Don't forget

http://www.archive.org/index.php

and one or two that maybe don't
want to be listed : )
And two dozen or more others
I won't tell you about unless you ask.


From waltah at earthlink.net  Wed Aug 31 15:06:36 2011
From: waltah at earthlink.net (Walt Hutchens)
Date: Wed, 31 Aug 2011 15:06:36 -0400
Subject: [HBR] The long, SLOW HBR project
In-Reply-To: <CA6D6BCA.6215%waltah@earthlink.net>
Message-ID: <CA83FE7C.759C%waltah@earthlink.net>

> I'll probably do a 20M oscillator coil next, just to see how that goes.

Done.   But what a bunch of work, with more to come.

Since I'm not building an established design (new oscillator circuit and
tracking tuning to an existing dial)  AND I'm making the coils from 1" Sch.
20 PVC pipe the coil work is t-e-d-i-o-u-s.   I'd guess 3 hours plus per
coil, down from about 10 hours on the first (80M) oscillator coil.

And -- as usual -- this was more educational than intended.

The W6TC (and many other multiband superhet) designs operate the LO on half
the needed frequency.   A trick they use that I've never seen discussed is
that feeding the LO to the same mixer grid as the signal lets the mixer grid
tuned circuit help select the harmonic signal over the (unwanted)
fundamental.

This tuned circuit won't be right on, but considering the fact that harmonic
injection is used only on 20M and up, it's not that far off, either.   The
impedance of the mixer tuned circuit will certainly be much higher on the
harmonic than on the fundamental.

Use of the second harmonic has the advantage that wiring and tube
capacitances and inductances, transit time, and other unwanted effects in
the LO are only half the percentage of the total circuit values, meaning
they have a smaller (percentage) effect on frequency.   A few hours
experimenting with a 12.3-12.78 Mcs local oscillator (existing dial is
calibrated 14-14.48 Mcs, IF 1.7 Mcs) convinced me that I wanted that
advantage.

Use of the 19J6 dual triode mixer with signal on one grid and LO on the
other made that impossible.  It's a great circuit but everything is a
compromise: I replaced it with a 19JN8, using the pentode section as a mixer
and connecting both signals to the control grid in a manner similar to the
HBR-series.

These tubes are always run very close to cutoff: Cathode resistors are 2400
to 12,000 ohms, depending on which design you look at.  I picked 2200 ohms,
pretty much out of thin air however a brief tour of the various handbooks
would be a good idea.

You'd expect some reduction in ability to handle very strong signals but I
haven't noticed anything yet.

One problem that resulted is that the former smooth slightly-humped-at-the-
edges passband is now two pronounced peaks with a valley in between and
audio quality has suffered accordingly.   This is most likely due to the
much higher plate resistance of the pentode mixer driving the half-lattice
crystal filter. 

With the mixer circuit change I was able to redo the 20M oscillator coil to
cover 6.15-6.39 Mcs.   Other than more than the usual number of assorted
wiring and arithmetic  mistakes (but practice with a slide rule is a good
thing!), that went smoothly and the oscillator is certainly more stable.

At least the antenna and mixer coils should be straightforward, right?   Err
... 80M being the broadest band (percentagewise) I was able to do those
coils by connecting the tuning cap across the whole coil.   And I neglected
to provide for bandspread on the other (narrower) bands.

One can either use a capacitor in series with the tuning cap or tap the coil
and hook the tuning cap across just a part of it.  Each way has advantages
but  the tapped coil seemed best in this case:  Fewer hard to find parts
(silver mica caps!)  are needed and it allows me to start by copying the
antenna and mixer coils of an existing HBR design.

Using a tapped coil, the tap has to be brought out for connection to the
tuning cap.   A few hours were devoted to rearranging the set wiring and
making new 80M antenna and mixer coils to conform.  Other minor things got
tidied up at the same time.

The next few hours went mostly to making up the 20M antenna and mixer coils.
Using the coil info for the 'Deluxe HBR' in the Bill Orr handbook these
coils came out right the first time.   They peak up at the right point and
tracking is in the ballpark, certainly tweakable to perfection.

The new problem is that gain on 20M is completely inadequate:   The 3.5 Mcs
band edge marker nearly pegs the S-meter on 80; the 4th harmonic on 14 Mcs
is only just audible and doesn't move the meter; only the strongest 20M sigs
can be heard at all.

The overall gain of this receiver is less than for the real HBRs.   That's
both a principle -- a whole bunch of gain you won't use is a whole bunch of
potential trouble you don't need -- and a consequence of designing with a
minimum number of stages and including a crystal filter having some loss.

It's not a big deal to boost the overall gain and it is time to do so.   I
think the double-hump passband of the filter can be fixed by better matching
to the mixer (more turns on the primary of the 1st IFT) and that will also
increase the gain.   That's next.

There are a couple of other things:  The IF and RF stages can be run at
higher gain.   (The 19JN8 pentodes are comparable to the 6BZ6 in gain -- in
other words, plenty hot enough for a receiver of this type and number of
stages.)   They're designed to work in FM receiver front ends -- even 10M is
no stretch, frequency wise.

The set is rock stable now -- no trace at all of regeneration -- so gain
increases shouldn't be a problem.   (Yeah ... that's what he said ...)

Raising the gain will force improvement of the AGC and/or BFO level
(whatever is the problem causing roughness on strong signals) but that has
to be done anyhow. 

When the gain is ample on 80M (rather than 'enough' as at present) it'll be
time to deal with the much lower gain on 20.   That almost has to be weak LO
injection.   There's lots to look at in that department.

The place to deal with band-to-band gain variation (that can't be fixed in
the LO/mixer circuitry) is in the coils.   I'm not eager to wind ANOTHER
set, but if that's what it takes ...

About the only good news from all the practice coil winding is that it is
easy to salvage the octal tube plug and APC cap from those that are replaced
-- I just cut off the top and bottom of the coil form and peel off the PVC
from the critical part.   Both the PVC cement on the APC and the JB Weld on
the plug work perfectly -- rock solid in use but come away clean for
recycling purposes.

Even the wire from discarded coils can be recycled into coils for higher
bands!

This was definitely the time to tackle a higher band as new issues were
exposed and possible solutions to a couple of known ones were narrowed.

Walt 
KJ4KV



From ollie.kolqk at juno.com  Sat Aug 27 20:10:10 2011
From: ollie.kolqk at juno.com (ollie.kolqk at juno.com)
Date: Sun, 28 Aug 2011 00:10:10 GMT
Subject: [HBR] (no subject)
Message-ID: <20110827.191010.11986.1@webmail04.dca.untd.com>

I have applied to this HBR list.  I have some parts, such as 82kc IF transformers.                              73                   W.Whyte"Ollie"  k0lqk
____________________________________________________________
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Sign up for Free to find out what the next 3000% Stock Winner is!
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