[R-390] RE: Washing your R-390A

[Craig Anderson Ext 1365]

As some one already pointed out, back in the old tube scope days
Tektronix actually washed their scopes.  I was in charge of our cal lab
back in the early 1970's and remember well the Tektronix folks putting
these in some kind of dish washer contraption.  They used a low foaming,
non-alkaline detergent that did not leave any residue after a thorough
rinse in distilled water.  You can get the same kind of detergent by
going to:

http://cleanosonic.com/cleaning_solutions.htm

I use these chemicals in a large commercial grade heated ultrasonic
cleaning tank.  I can get an entire R-390A RF deck in the tank.  Amazing
results!

Craig W9CLA

-----Original Message-----
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Sent: Sunday, March 19, 2006 3:26 PM
To: r-390 at mailman.qth.net
Subject: R-390 Digest, Vol 23, Issue 32

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Today's Topics:

   1. Hosing those 390A, a short pictorial (Fernando Quinones N2FQ)
   2. Cosmos PTO (mfisch at kent.edu)
   3. Re: Cosmos PTO (Tim Shoppa)
   4. Calibration issue (Jon)
   5. RE: Where would you start? (Tracy Fort)
   6. RE: Hosing those 390A, a short pictorial (Bill Hawkins)
   7. Re: Hosing those 390A, a short pictorial (ToddRoberts2001 at aol.com)
   8. Re: Where would you start? (Barry)
   9. R-390A Front Panel restoration (TChirhart)


----------------------------------------------------------------------

Message: 1
Date: Sun, 19 Mar 2006 09:22:34 -0800
From: Fernando Quinones N2FQ <n2fq at sbcglobal.net>
Subject: [R-390] Hosing those 390A, a short pictorial
To: r-390 at mailman.qth.net
Message-ID: <475BF677-AEA9-48DE-8BD8-D263AA692D49 at sbcglobal.net>
Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed

Hello to all.

Awhile back I posted a picture of my R-90A's in a rack, which all  
needed a good cleaning.
So.. after reading previous posts here as to how go about it, I  
decided what someone
suggested but never shown, that is to  hosed them down.

I used Simple Green and a water hose, perhaps I committed HariKari.
Here are some pictures for your enjoyment.

< http://pages.sbcglobal.net/nf6q/R-390A's/R-390A's.html >

Oh.. the darn thing are to heavy for my oven self, so they are  
bathing in the California Sun. hi

While I'm at it, let make a plug now. To subsidize the rebuild of two  
of my keepers,
I'm selling two R-390As (Collins), one with engrave panel and the  
other with decals,
they both work by the way, as well as the SSB Adapter ( never plug in  
so don't know if it works or not, but all there).

Please contact me off list if interested.

Fernando  N2FQ
<http://pages.sbcglobal.net/n2fq>





------------------------------

Message: 2
Date: Sun, 19 Mar 2006 12:31:52 -0500
From: <mfisch at kent.edu>
Subject: [R-390] Cosmos PTO
To: r-390 at mailman.qth.net, <r-390 at mailman.qth.net>
Message-ID: <558eb02558aeb1.558aeb1558eb02 at kent.edu>
Content-Type: text/plain; charset=us-ascii

Hi:

I know there is a lot about the Cosmos PTO out there, but nerves have
got the best of me.  I want to adjust the end point (out by about 1 kHz)
and I took off the screw to adjust the end point, but the end point
adjustment screw looks like a spanner nut with a rubber center.  Do I
just take a 1/8 inch blade screwdriver and have ho or is there something
I need to be careful of?  I was expecting a slot and it looks like I
should stone a screwdriver to have parallel sides.  Is this the case?
Thanks in advance.

Mike


------------------------------

Message: 3
Date: Sun, 19 Mar 2006 12:44:53 -0500
From: shoppa_r390a at trailing-edge.com (Tim Shoppa)
Subject: Re: [R-390] Cosmos PTO
To: r-390 at mailman.qth.net, mfisch at kent.edu
Message-ID: <20060319174453.41D858C009F at mini-me.trailing-edge.com>
Content-Type: text/plain; charset=us-ascii

<mfisch at kent.edu> wrote:
> I know there is a lot about the Cosmos PTO out there, but nerves have
> got the best of me.  I want to adjust the end point (out by about 1
kHz)
> and I took off the screw to adjust the end point, but the end point
> adjustment screw looks like a spanner nut with a rubber center.  Do I
> just take a 1/8 inch blade screwdriver and have ho or is there
something
> I need to be careful of?  I was expecting a slot and it looks like I
> should stone a screwdriver to have parallel sides.  Is this the case?
> Thanks in advance.

Well, two months ago I didn't know what a Cosmos expert was, now I is
one!

There are three "holes". The endpoint one is the one that is
partially obscured by the transformer can. Removing the can
might help get you access (especially if you have a stiff-bladed
driver). BUT... I think there is "hot" wiring inside the transformer
can so be careful if you do so. If you do not remove the transformer
can you can use a metal screwdriver without fear.

The one next to the endpoint hole reveals all the little linearity
adjustment screws. (I bought the 4-flute spline driver for these
from McMaster, let me know if any of you need the official McMaster
part number.)

And there's a third hole that reveals the thermostat set point.
This is a BIG (in comparison) brass screw.

Not sure what a "spanner nut with a rubber center" is, but the
endpoint inductor has a brass three-wing section that has an
external nut which can tighten down on the brass adjustment
screw. I think the purpose of the three-wing section is that it
is adjusted to minimize wiggling/backlash of the internal brass
adjustment screw. The brass screw is attached to the slug.

If you find you do not have enough adjustment range, you probably
have to open to the PTO can and adjust the turns on the inductor.
Others talk about removing whole turns, but for mine I found that
removing half a turn (reversing the direction of the winding so it
went from 2.75 turns to 2.25 turns) was the best choice. In my
case removing a whole turn took me too far in the direction of
increasing the span. But removing half a turn got me in the
"sweet spot". Since you're only 1kHz off in endpoint, maybe you
don't have to do this surgery. But if you find yourself with the
brass screw all the way inside the three-wing clamper, or sticking
out so far it would interfere with the threaded cover, then maybe
it's time.

Tim.


------------------------------

Message: 4
Date: Sun, 19 Mar 2006 13:12:26 -0500
From: "Jon" <jonklinkhamer at comcast.net>
Subject: [R-390] Calibration issue
To: "R-390 at Mailman. Qth. Net" <r-390 at mailman.qth.net>
Message-ID: <MDBBIGOKDBHJANFFCODCMEJJCHAA.jonklinkhamer at comcast.net>
Content-Type: text/plain;	charset="iso-8859-1"

Hello Group,

I'm in the process of going thru electrical calibration on my R390A. I
noticed a couple of things when I turned on the calibration signal.
After I
zero adjusted it to achieve zero beat frequency I can basically do two
things in which I would have to zero beat it again. First by just going
+/-
say 50khz (or maybe even less) around the calibration point, in this
case
09.000  I would have to re zero and there would be a good tone not just
a
little off beat. The other observation is by just sitting on the
calibration
mark and returning after about 15 minutes it again would be off. However
not
as bad. BTW the receiver has been warmed up for at least 2 hours in
advance.
I guess I'm trying to pin down whether the BFO or PTO is drifting or
maybe
the 100Khz signal is off.

Thanks,
Jon, KB1Dc



------------------------------

Message: 5
Date: Sun, 19 Mar 2006 13:05:59 -0500
From: "Tracy Fort" <beerbarrel at cox.net>
Subject: RE: [R-390] Where would you start?
To: "'Francesco Ledda'" <frledda at verizon.net>,	<R-390 at mailman.qth.net>
Message-ID: <000301c64b7f$c72c5920$6400a8c0 at TracyDonna>
Content-Type: text/plain;	charset="US-ASCII"

Thanks for all the replies guys. I write this as I sit here red
faced....

It's amazing what happens when you put the Diode load jumper back
in.....

Tracy

-----Original Message-----
From: Francesco Ledda [mailto:frledda at verizon.net] 
Sent: Saturday, March 18, 2006 8:40 AM
To: Tracy Fort; R-390 at mailman.qth.net
Subject: RE: [R-390] Where would you start?


What kind of speaker are you using?

-----Original Message-----
From: r-390-bounces at mailman.qth.net
[mailto:r-390-bounces at mailman.qth.net]On
Behalf Of Tracy Fort
Sent: Saturday, March 18, 2006 6:33 AM
To: R-390 at mailman.qth.net
Subject: RE: [R-390] Where would you start?



Paolo,

I'm so-so at it. I'm not close to an expert though. I do have the
manual. I
was just hunting quick things to check. I can't tell is sensitivity is
Ok
because volume is quite low. At this point, I'm thinking that it's only
audio. I'm think I might check for the leaky cap at V507 tube socket. I
lose
volume completely if I turn off limiter switch.

Thanks,
Tracy

-----Original Message-----
From: paolo gramigna [mailto:paolo.gramigna at controllo.it]
Sent: Saturday, March 18, 2006 7:20 AM
To: 'Tracy Fort'
Subject: R: [R-390] Where would you start?



Are you familiar with servicing a vacuum tube radio? Do you have the
R-390A
manual? You can get it here: http://www.hausernet.com/r390a/ if you
don't.
those radio will loose plenty of sensitiviti if just one of the RF slugs
is
off by a millimeter or so. You will need a few test instruments, and a
few
special tools (bristol key). Let me know about your situation...

Paolo


-----Messaggio originale-----
Da: r-390-bounces at mailman.qth.net [mailto:r-390-bounces at mailman.qth.net]
Per
conto di Tracy Fort
Inviato: sabato 18 marzo 2006 12.53
A: R-390 at mailman.qth.net
Oggetto: RE: [R-390] Where would you start?

I got carrier level to come up but no audio impoovement.

Tracy

-----Original Message-----
From: r-390-bounces at mailman.qth.net
[mailto:r-390-bounces at mailman.qth.net]
On Behalf Of Tracy Fort
Sent: Saturday, March 18, 2006 6:42 AM
To: R-390 at mailman.qth.net
Subject: [R-390] Where would you start?


Just got a new 390a the other day. It seems to have arrived with a
little
problem. It has extremely low audio output. I don't know if something
was
shaken loose in shipping or not but it all looks good and was packed
well.
Tuned to a local AM station with rf gain and audio maxed out I can
barely
hear audio. I get very little carrier reading. It's slightly above zero.
No
movement on the line meter either. I'm trying to figure out if it was
working OK before it was shipped and am waiting on a response from the
seller. I'm pretty sure that it was but wanted to make sure before I
started
getting to deep into it. Are there any problems that jump out at anyone
right away that could be easy to check?

Tracy

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------------------------------

Message: 6
Date: Sun, 19 Mar 2006 12:44:17 -0600
From: "Bill Hawkins" <bill at iaxs.net>
Subject: RE: [R-390] Hosing those 390A, a short pictorial
To: "Fernando Quinones N2FQ" <n2fq at sbcglobal.net>,
	<r-390 at mailman.qth.net>
Message-ID: <014f01c64b85$2097f140$0500a8c0 at darius.domain.actdsltmp>
Content-Type: text/plain;	charset="iso-8859-1"

Fernando,

It's been my experience that spraying detergent just irritates the
dirt without removing it. You need a soft bristle brush to break it
loose. Soft bristles so you don't break any wires. Detergent is
pretty good at removing the identification from the tubes.

Any detergent or even hard water can leave a conductive residue.
Tektronix service people used to wash the big scopes with detergent
and then follow with a distilled water rinse. The conductive residue
can drop the Q of coils or change the value of trimmer caps.

It might not be too late to rinse, but once hard water deposits dry,
they're hard to remove. Don't allow water to sit around after you
rinse. Use canned or compressed air to blow water out of sockets
and other places it can get into, then leave it to dry.

I've washed and rinsed many Tek scopes and other pieces of test
equipment. They always worked fine afterwards. Never tried to wash
a 390 class radio, though.

Bill Hawkins


-----Original Message-----
From: r-390-bounces at mailman.qth.net
[mailto:r-390-bounces at mailman.qth.net]On Behalf Of Fernando Quinones
N2FQ
Sent: Sunday, March 19, 2006 11:23 AM
To: r-390 at mailman.qth.net
Subject: [R-390] Hosing those 390A, a short pictorial


Hello to all.

Awhile back I posted a picture of my R-90A's in a rack, which all  
needed a good cleaning.
So.. after reading previous posts here as to how go about it, I  
decided what someone
suggested but never shown, that is to  hosed them down.

I used Simple Green and a water hose, perhaps I committed HariKari.
Here are some pictures for your enjoyment.

< http://pages.sbcglobal.net/nf6q/R-390A's/R-390A's.html >

Oh.. the darn thing are to heavy for my oven self, so they are  
bathing in the California Sun. hi

While I'm at it, let make a plug now. To subsidize the rebuild of two  
of my keepers,
I'm selling two R-390As (Collins), one with engrave panel and the  
other with decals,
they both work by the way, as well as the SSB Adapter ( never plug in  
so don't know if it works or not, but all there).

Please contact me off list if interested.

Fernando  N2FQ
<http://pages.sbcglobal.net/n2fq>



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------------------------------

Message: 7
Date: Sun, 19 Mar 2006 14:31:33 EST
From: ToddRoberts2001 at aol.com
Subject: Re: [R-390] Hosing those 390A, a short pictorial
To: r-390 at mailman.qth.net
Message-ID: <2a0.78c413a.314f0b95 at aol.com>
Content-Type: text/plain; charset="US-ASCII"

In a message dated 3/19/2006 12:25:43 PM Eastern Standard Time, 
n2fq at sbcglobal.net writes:
I used Simple Green and a water hose, perhaps I committed HariKari.
Here are some pictures for your enjoyment.

Hi Fernando, thanks for the interesting pictures of your R-390As being 
sprayed with simple green and hosed off with a garden hose. There are
several things 
I would worry about with this procedure. It looks like you left the
tubes in 
their sockets? The dirt and muck loosened up from the simple green and
water 
could settle in the sockets causing problems? I would also worry about
water 
possibly migrating into the fiberlass insulation in the crystal oven and
PTO and 
just sitting in there wet unless the covers were removed and allowed to 
air-dry. Not likely but water could get into the meters and it could
also get 
inside the carbon pots and RF/IF transformer cans and sit in there. The
only thing 
I would dare to give the radio like the R-390A a bath in would be
something 
non-conductive like Kerosene or Diesel fuel. In that case you have to
remove the 
small ceramic trimmers or else the kerosene will get into the rubber
gaskets 
and cause them to swell up, but normally kerosene will not rust or short
out 
electronic components. But your radios may turn out just fine if
everything is 
allowed to thoroughly dry. I know people have rebuilt the Blue-Stripers
and 
they were sitting out in the weather and rain for who knows how long. I
once 
washed and hosed off a really dirty SP-600 with soap and water and it is
the best 
working SP-600 I have. I put it in front of a dehumidifier for 3-4 days
and 
it was bone dry but I did have to take the meter apart to dry it and
took off 
all the covers from the IF cans, etc.to air dry the innards.  Good luck
and let 
us know how the R-390As turn out!  73 Todd WD4NGG


------------------------------

Message: 8
Date: Sun, 19 Mar 2006 14:30:51 -0600
From: "Barry" <n4buq at knology.net>
Subject: Re: [R-390] Where would you start?
To: "Tracy Fort" <beerbarrel at cox.net>, <R-390 at mailman.qth.net>
Message-ID: <002c01c64b94$03f70080$6401a8c0 at knology.net>
Content-Type: text/plain;	charset="iso-8859-1"

Tracy,

A few weeks ago, I replaced some out-of-spec components on the underside
of
one of my IF decks.  When I put it back in place, I noticed the
bandwidth
selector no longer had any effect.  I got the same bandwidth no matter
what
position I selected.  I scratched my head for a while and then realized
I
had removed the bandwidth selector switch's shaft (the one that connects
it
to the front panel of the IF deck) so I could more easily get to some of
the
parts.  Duh.

As if that wasn't enough, a week or so ago, I was fiddling around with
the
5814A's in the same IF deck.  I was seeing the differences one tube or
the
other made in the AGC amplifier socket.  One of them gives good grid
voltage
and the others don't.  When I started trying to listen to it again, I
noticed some of the same symptoms you describe.  I then looked and
noticed I
had failed to plug one of the 5814A's fully back into its socket.

Those kind of things happen.  ;-)

Barry - N4BUQ


----- Original Message -----
From: "Tracy Fort" <beerbarrel at cox.net>
To: "'Francesco Ledda'" <frledda at verizon.net>; <R-390 at mailman.qth.net>
Sent: Sunday, March 19, 2006 12:05 PM
Subject: RE: [R-390] Where would you start?


Thanks for all the replies guys. I write this as I sit here red
faced....

It's amazing what happens when you put the Diode load jumper back
in.....

Tracy

-----Original Message-----
From: Francesco Ledda [mailto:frledda at verizon.net]
Sent: Saturday, March 18, 2006 8:40 AM
To: Tracy Fort; R-390 at mailman.qth.net
Subject: RE: [R-390] Where would you start?


What kind of speaker are you using?

-----Original Message-----
From: r-390-bounces at mailman.qth.net
[mailto:r-390-bounces at mailman.qth.net]On
Behalf Of Tracy Fort
Sent: Saturday, March 18, 2006 6:33 AM
To: R-390 at mailman.qth.net
Subject: RE: [R-390] Where would you start?



Paolo,

I'm so-so at it. I'm not close to an expert though. I do have the
manual. I
was just hunting quick things to check. I can't tell is sensitivity is
Ok
because volume is quite low. At this point, I'm thinking that it's only
audio. I'm think I might check for the leaky cap at V507 tube socket. I
lose
volume completely if I turn off limiter switch.

Thanks,
Tracy

-----Original Message-----
From: paolo gramigna [mailto:paolo.gramigna at controllo.it]
Sent: Saturday, March 18, 2006 7:20 AM
To: 'Tracy Fort'
Subject: R: [R-390] Where would you start?



Are you familiar with servicing a vacuum tube radio? Do you have the
R-390A
manual? You can get it here: http://www.hausernet.com/r390a/ if you
don't.
those radio will loose plenty of sensitiviti if just one of the RF slugs
is
off by a millimeter or so. You will need a few test instruments, and a
few
special tools (bristol key). Let me know about your situation...

Paolo


-----Messaggio originale-----
Da: r-390-bounces at mailman.qth.net [mailto:r-390-bounces at mailman.qth.net]
Per
conto di Tracy Fort
Inviato: sabato 18 marzo 2006 12.53
A: R-390 at mailman.qth.net
Oggetto: RE: [R-390] Where would you start?

I got carrier level to come up but no audio impoovement.

Tracy

-----Original Message-----
From: r-390-bounces at mailman.qth.net
[mailto:r-390-bounces at mailman.qth.net]
On Behalf Of Tracy Fort
Sent: Saturday, March 18, 2006 6:42 AM
To: R-390 at mailman.qth.net
Subject: [R-390] Where would you start?


Just got a new 390a the other day. It seems to have arrived with a
little
problem. It has extremely low audio output. I don't know if something
was
shaken loose in shipping or not but it all looks good and was packed
well.
Tuned to a local AM station with rf gain and audio maxed out I can
barely
hear audio. I get very little carrier reading. It's slightly above zero.
No
movement on the line meter either. I'm trying to figure out if it was
working OK before it was shipped and am waiting on a response from the
seller. I'm pretty sure that it was but wanted to make sure before I
started
getting to deep into it. Are there any problems that jump out at anyone
right away that could be easy to check?

Tracy



------------------------------

Message: 9
Date: Sun, 19 Mar 2006 16:22:55 -0500
From: "TChirhart" <sparks at codepoets.com>
Subject: [R-390] R-390A Front Panel restoration
To: <R-390 at mailman.qth.net>
Message-ID: <000001c64b9b$4ad64bd0$7001a8c0 at warnerp93v1mse>
Content-Type: text/plain;	charset="us-ascii"

Can anyone recommend where to get an R-390 front panel painted and
re-lettered? It has the engraved panel. I have an Imperial 1963 that has
the off Grey/Green front panel and I'd like to keep it the same color.
The reasoning is that the 1956 vintage US Navy Destroyer I served 30
plus years ago had these same receivers with the same color front
panels. The rear of the panel could be used for color matching and the
only part I want painted in the front panel and perhaps the edges and
outer margin on the rear. This color scheme matches the LS-474 speakers
which I have. This color is not the typical Battleship Grey that most of
us are accustomed to seeing. What is interesting is that the interior of
the tin can I was on pretty well matched this color as well. The color
is typical of the R-1051 line. Thanks in advance. 73's to all. Tom K4NCG




------------------------------

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End of R-390 Digest, Vol 23, Issue 32
*************************************