[Boatanchors] Boatanchors Digest, Vol 126, Issue 20
Ron Bussiere via Boatanchors
boatanchors at mailman.qth.net
Wed Jul 23 12:35:22 EDT 2014
My latest "collectable", is a FR-149/USM-159. These are more modern Freq Meters that cover from 125 KHz to 1 GHz. They are solid state and can be operated from 6 D batteries. They have a very long, back lit tape drive with 3 segments. Really cool.
I have purchased several of these on eBay and the price is usually low, but they are heavy and shipping is NOT cheap any more. They are usually on there from cheap $ to insane $. Beware of ones for sale without the calibration tables....
The manuals are free on the www and these things are built tough as nails. All of mine but one came with the front cover. 2 were missing the power cords. I politely asked the sellers to pack the units carefully and they all arrived unharmed.
The best thing is, that all cleaned up 100% and look and function like new.
I also have a bunch of the old 221 series, but these are a quantum leap better......
ron
N4UE
-----Original Message-----
From: boatanchors-request <boatanchors-request at mailman.qth.net>
To: boatanchors <boatanchors at mailman.qth.net>
Sent: Wed, Jul 23, 2014 11:08 am
Subject: Boatanchors Digest, Vol 126, Issue 20
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Today's Topics:
1. Re: LM-13 Frequency Meter (Bill Cromwell)
2. Re: LM-13 Frequency Meter (Bill Cromwell)
3. Re: LM-13 Frequency Meter (Dave Brown)
4. Re: LM-13 Frequency Meter (Pete Lancashire)
5. Re: LM-13 Frequency Meter (Dave Brown)
----------------------------------------------------------------------
Message: 1
Date: Tue, 22 Jul 2014 09:16:06 -0400
From: Bill Cromwell <wrcromwell at gmail.com>
To: boatanchors at mailman.qth.net
Subject: Re: [Boatanchors] LM-13 Frequency Meter
Message-ID: <53CE6416.1000007 at gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Hi Brian, and anyone else interested,
The heterodyne frequency meters (LM, BC221, others) can be used to
measure the frequency of our oscillators and other signals. These days a
digital frequency counter can do that of course. But the LMs can do
tricks the digital counters cannot do. The LMs can detect and measure
the frequency of other oscillators OR the LM can supply the marker for
your receiver - not at 100kc or 25 kc "steps" but right on the frequency
you want to tune.
Hams and experimenters who do not have one of these should get one,
maintain it, and use the bejeepers out of it. I already have two LMs and
I have waited for others who might not have one to speak up for the one
being offered by Jack. If the hacking disturbs you then maybe make an
offer for one of Brian's working machines. Don't be put off by an LM
without the original book (matching serial numbers). You can generate a
new book or tuning chart with a little effort and a computer. Does
everybody here have a computer? <evil grin>
For an example of the utility - a short, true story. I have a RAK-7 - a
large, low frequency regenerative receiver that was once use by the U.S.
Navy and some merchant vessels. The beast has extensive shielding inside
the metal cabinet and two rf amplifiers. The rf amps are not to increase
sensitivity but to isolate the oscillating detector from the antenna and
to control incoming signal levels. It has a log scale that can resolve
incoming signals to a few cycles per second with care. For CW operation
that is a great plenty. I wanted to check the calibration of of the dial
and make a new tuning chart (the old one was decades out of date). I
poked the end of a wire inside a small hole in the case with the other
end connected to the digital counter. Nothing. I connected the antenna
terminal directly to the counter. Nothing. I listened for the RAK on the
LM. Nothing. Then I listened for the LM with the RAK. I got my results!
Try that every few kc across the dial with your digital counter!
73,
Bill KU8H
On 07/22/2014 07:59 AM, Brian Clarke wrote:
> Hello Jack, and anyone else interested,
>
> The LM and BC-221 heterodyne frequency meters are designed to produce
> very many harmonics. Consequently, they are not good for VFO service.
> Sure they are stable, and you can dial up a frequency quite
> accurately, at least within 10 to 15 Hz of the on-board calibration
> xtal (the limit of resolution is the lowest frequency your headphones
> can reproduce and that your ears can discern - to get 10 to 15 Hz, you
> need really good cans). As a driver for a VLF, MF or HF transmitter,
> you would need to add filtration to attenuate the harmonics. To
> produce a shop standard, I have upon occasion added a 6AK5 and a short
> antenna.
>
> I have a few LM and BC-221 series with the correct frequency book, the
> calibrated crystal and all tubes. I even have one with all the spare
> tubes and a spare crystal. There are no extra holes, unlike Jack's one
> illustrated in his photobucket library. All the original components
> and wiring are still there - especially that wonderful Cardwell
> variable capacitor. I have one or possibly two mains power supplies
> for them. I have no need for so many het freq meters. So, if someone
> would like to make me an offer ....
>
> 73 de Brian, VK2GCE.
>
------------------------------
Message: 2
Date: Tue, 22 Jul 2014 09:22:10 -0400
From: Bill Cromwell <wrcromwell at gmail.com>
To: boatanchors at mailman.qth.net
Subject: Re: [Boatanchors] LM-13 Frequency Meter
Message-ID: <53CE6582.6040807 at gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Hi there Jack,
I will take the LM for the shipping costs if nobody else wants it. I
already have two but I don't want to see a working LM go into the
scrapper. I have already fixed up a couple of other orphans and donated
them to other, newer hams along with some demonstrations about how to
use them. At my qth that LM will be able to 'soldier on'. So wait a
little longer and if no other takers then figure the postage to 48630
and I'll send you the money.
73,
Bill KU8H
On 07/21/2014 10:28 AM, Holzer wrote:
> LM-13 freq meter free for shipping from 66212. At the Warrensburg MO
> hamfest I saw this and thought it was a really neat looking item and
> would make a nice VFO. I am usually good at resisting temptation but
> every time I walked by that table it would whimper "buy me", "buy me".
> Anyway when I got it home this is what I found: The good news is that
> it has the original calibration book and actually works! The bad news
> is that someone had removed all the vacuum tubes and associated
> resistors and capacitors and had transistorized it but done a poor
> job. They had also drilled air holes in the cabinet. I note that all
> the critical components of the original meter are still there so I
> suppose it would be possible to re-install the tubes, sockets, etc., a
> job I am not interested in doing. Another option is that it would make
> a good parts source. Pictures at:
>
> http://s909.photobucket.com/user/jackholzer/library/LM-13%20Frequency%20Meter
>
>
>
>
>
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------------------------------
Message: 3
Date: Wed, 23 Jul 2014 09:36:41 +1200
From: "Dave Brown" <tractorb at ihug.co.nz>
To: <boatanchors at mailman.qth.net>
Subject: Re: [Boatanchors] LM-13 Frequency Meter
Message-ID: <15C3E9EC656A4D6F828CC06476E3D646 at athlon3200>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=response
Were the LMs designed for a much higher HT voltage than the BC-221 series?
I have a couple of LMs here. One is virtually original- complete with
canvas cover and has not been powered on in a long time but I'm in the
process of sorting out a power supply for it. Which raised the
question-what should the HT supply voltage be? The other one has a
'commercial' PSU associated with it of UK origin which delivers 300 volts HT
and it drifts significantly- possibly as a result of the HT being too
high-or at least thats what I thought. I know the BC-221 used a battery
supply around 90 volts for the HT but - what was the original power supply
arrangement for the LM series and what was the nominal HT?
73
Dave
ZL3FJ
------------------------------
Message: 4
Date: Tue, 22 Jul 2014 14:53:59 -0700
From: Pete Lancashire <pete at petelancashire.com>
To: Dave Brown <tractorb at ihug.co.nz>
Cc: Boat Anchors List <boatanchors at mailman.qth.net>
Subject: Re: [Boatanchors] LM-13 Frequency Meter
Message-ID:
<CAA-F0u-+sBAouixq2gSnEjj_tGx+E6rO4H5Or+P1JeNgApp+zA at mail.gmail.com>
Content-Type: text/plain; charset=UTF-8
These may help answer the B+ question
http://www.vk2bv.org/museum/lm.htm
http://www.pa3esy.nl/military/us/meet/LM20/pdf/LM-13.pdf
On Tue, Jul 22, 2014 at 2:36 PM, Dave Brown <tractorb at ihug.co.nz> wrote:
> Were the LMs designed for a much higher HT voltage than the BC-221 series?
> I have a couple of LMs here. One is virtually original- complete with canvas
> cover and has not been powered on in a long time but I'm in the process of
> sorting out a power supply for it. Which raised the question-what should
> the HT supply voltage be? The other one has a 'commercial' PSU associated
> with it of UK origin which delivers 300 volts HT and it drifts
> significantly- possibly as a result of the HT being too high-or at least
> thats what I thought. I know the BC-221 used a battery supply around 90
> volts for the HT but - what was the original power supply arrangement for
> the LM series and what was the nominal HT?
> 73
> Dave
> ZL3FJ
> ______________________________________________________________
> Boatanchors mailing list
> Home: http://mailman.qth.net/mailman/listinfo/boatanchors
> Help: http://mailman.qth.net/mmfaq.htm
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>
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer at usol.com **
>
>
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------------------------------
Message: 5
Date: Wed, 23 Jul 2014 10:32:54 +1200
From: "Dave Brown" <tractorb at ihug.co.nz>
To: "Boat Anchors List" <boatanchors at mailman.qth.net>
Subject: Re: [Boatanchors] LM-13 Frequency Meter
Message-ID: <E48B6E92A4994DBDBD56DDD6B248F2AA at athlon3200>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Thanks Pete. That handbook provides all the answers. I wasn't aware of the
power supply HT options built in.
I better look into the one I have with the drift issue as it may not have
been strapped properly for the higher HT rail.
In any case - the lower the better these days- I'll try with 150 initially
for the other one and see if its making enough 'noise' to be useable at
that.
73
Dave, ZL3FJ
----- Original Message -----
From: "Pete Lancashire" <pete at petelancashire.com>
To: "Dave Brown" <tractorb at ihug.co.nz>
Cc: "Boat Anchors List" <boatanchors at mailman.qth.net>
Sent: Wednesday, July 23, 2014 9:53 AM
Subject: Re: [Boatanchors] LM-13 Frequency Meter
> These may help answer the B+ question
>
> http://www.vk2bv.org/museum/lm.htm
>
> http://www.pa3esy.nl/military/us/meet/LM20/pdf/LM-13.pdf
>
> On Tue, Jul 22, 2014 at 2:36 PM, Dave Brown <tractorb at ihug.co.nz> wrote:
>> Were the LMs designed for a much higher HT voltage than the BC-221
>> series?
>> I have a couple of LMs here. One is virtually original- complete with
>> canvas
>> cover and has not been powered on in a long time but I'm in the process
>> of
>> sorting out a power supply for it. Which raised the question-what should
>> the HT supply voltage be? The other one has a 'commercial' PSU
>> associated
>> with it of UK origin which delivers 300 volts HT and it drifts
>> significantly- possibly as a result of the HT being too high-or at least
>> thats what I thought. I know the BC-221 used a battery supply around 90
>> volts for the HT but - what was the original power supply arrangement for
>> the LM series and what was the nominal HT?
>> 73
>> Dave
>> ZL3FJ
>> ______________________________________________________________
>> Boatanchors mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/boatanchors
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:Boatanchors at mailman.qth.net
>> Message delivered to xyzzypdx at gmail.com
>>
>> List Administrator: Duane Fischer, W8DBF
>> ** For Assistance: dfischer at usol.com **
>>
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
> ______________________________________________________________
> Boatanchors mailing list
> Home: http://mailman.qth.net/mailman/listinfo/boatanchors
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> Post: mailto:Boatanchors at mailman.qth.net
> Message delivered to tractorb at ihug.co.nz
>
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer at usol.com **
>
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
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