"COLIN LAMB" wrote in message
m...
Hello Richard:

I think the Cardwell company was owned by another company,
which was owned by the Cardwell family. At some point,
during the demise of Hammarlund, that company purchased
the Hammarlund assets.

The specified audio output of the Cardwell receivers is
high enough that it was probably push-pull. So, if you
ever find one, the audio will probably be good.

I just had a thought about searching for this elusive
receiver. Check the various manual sources. If there
were a few radios made, there must have been a manual
floating around. Fun to see one.

73, Colin K7FM
I think so too. I'm not quite sure what happened to
either Hammarlund or Cardwell. There is some Hammarlund
history on the web. At the time the Cardwell RX went on the
market a number of receivers had relatively high quality
push-pull output stages. The Hammarlund Super-Pro for one
and a couple of National receivers, I think the SX-28 and
SX-32 had push-pull amps. I can testify as the owner of a
BC-779 that the low distortion helps even with CW since
distortion magnifies noise. Those having receivers with an
external connection to the detector may get surprize if this
is connected to a high quality audio system. Most of these
connections have DC on them so a series capacitor and a
resistor are necessary. An SP-600, for instance, will let
you hear all the clipping from the processing on AM
broadcast stations. There WAS, dear children, high-quality
AM in the dear, dead, long ago before being the loudest kid
on the block became the objective.
(I have created an alternative signature, here it is)

--
Richard Knoppow
Los Angeles
WB6KBL

Found data. From September 1946 QST, page 117, full page ad for the
Cardwell Fifty-Four.

1. Full turret R.F. Section
2. Wide coverage with coil strips to 40 mc - extra strip goes to 54 mc.
3. 100 and 1000 kc calibrator.
4. 5 degrees of selcetivity.
5. New noise limiter.
6. Band spread dial calibrated directly.
7. 10.5 inch direct reading dial.
8. Temperature compensated oscillator.
9. (This is an interesting one). Mechanical control shafts are brought out
back of set for linkage to other units, such as excited or transmitter. Can
you imagine the tracking nightmare for the homecuilder?
10. All aluminum construction (still weighs 78 lbs).
11. Push-pull class A-B output (8 watts).
12. 18 tubes - all miniature.
13. Panoramic adapter jack.
14. Threshold squelch.

They claimed they had a technical bulletin.

In the October 1946 issue, there is a full page ad with a drawing of the
receiver. The technical article was signed by Mack C. Jones. Said a
technical bulletin was available.

Cardwell ad for November and December 1946 was for other products.

Will research 1947 next.

Colin K7FM

And, as we move on to 1947, there is no ad in QST by the Cardwell Company.

I would take a wild guess, based upon my experience over the years, that the
company spent so much money on development of the CR-54 that they finally
threw in the towel and that none got out the door. I have seen what appears
to be photos, though, so there may be one that was made. But, the technical
bulletin should be around, so you can drool a bit.

73, Colin K7FM

I can add some information, based on research done back in 1980 by H.
L. Chadbourne of La Jolla, CA. Quoting from a letter of his to me:

"...I saw the name Ray Morehouse with call letters attached to one of
these ads [the QST ads] , so I looked him up in a recent callbook and
wrote him. Had a very nice letter back. He'd worked for Cardwell from
1924-1947. He had a little on the receiver, but referred me to Moe
Joffe in Los Angeles for more. Moe was directly in on the project.

....Allen D. Cardwell...toward the war's end...wanted to broaden the
product line. He talked with Grenby Mfg. Co. of Plainview, CT about
some sort of joint venture, with Cardwell doing R&D and Grenby as the
manufacturing arm. Grenby had started in 1940 and during WWII made
mainly parts for Pratt & Whitney. It was a sort of machine shop
operation. However at one point Lockheed gave them an electronic
assembly to make, and they liked the work, so decided on it for
postwar. Hence the Cardwell discussions. But the two firms could not
reach agreement and the talks ended by Grenby buying out Cardwell and
moving the firm to Plainville. Mack C. Jones, who had been an
engineer with Raytheon during WWII, was hired by Grenby as Ch.
Engineer, and he suggested the 54 receiver project. Moe Joffe was
under him.

"I had a fine phone conversation with Joffe and hope some time to
interview him in person. He said the 54 was a very advanced set, but
was not put into production because of its extremely high cost, $700 -
$800 a unit. The market did not seem to be there at the
time--possibly again, the huge supply of surplus put a damper on new
sales. Joffe eventually went on to Squires-Sanders and their
communications receiver projects."

I have Morehouse's letter here also; he said he didn't know what
became of the 54 prototype.

Alan

"Alan Douglas" adouglasatgis.net wrote in message
...
I can add some information, based on research done back in
1980 by H.
L. Chadbourne of La Jolla, CA. Quoting from a letter of
his to me:

"...I saw the name Ray Morehouse with call letters
attached to one of
these ads [the QST ads] , so I looked him up in a recent
callbook and
wrote him. Had a very nice letter back. He'd worked for
Cardwell from
1924-1947. He had a little on the receiver, but referred
me to Moe
Joffe in Los Angeles for more. Moe was directly in on the
project.

...Allen D. Cardwell...toward the war's end...wanted to
broaden the
product line. He talked with Grenby Mfg. Co. of Plainview,
CT about
some sort of joint venture, with Cardwell doing R&D and
Grenby as the
manufacturing arm. Grenby had started in 1940 and during
WWII made
mainly parts for Pratt & Whitney. It was a sort of
machine shop
operation. However at one point Lockheed gave them an
electronic
assembly to make, and they liked the work, so decided on
it for
postwar. Hence the Cardwell discussions. But the two
firms could not
reach agreement and the talks ended by Grenby buying out
Cardwell and
moving the firm to Plainville. Mack C. Jones, who had
been an
engineer with Raytheon during WWII, was hired by Grenby as
Ch.
Engineer, and he suggested the 54 receiver project. Moe
Joffe was
under him.

"I had a fine phone conversation with Joffe and hope some
time to
interview him in person. He said the 54 was a very
advanced set, but
was not put into production because of its extremely high
cost, $700 -
$800 a unit. The market did not seem to be there at the
time--possibly again, the huge supply of surplus put a
damper on new
sales. Joffe eventually went on to Squires-Sanders and
their
communications receiver projects."

I have Morehouse's letter here also; he said he didn't
know what
became of the 54 prototype.

Alan

Very interesting and more than is known about some
other projects. Note that the cost of the SP-600 and 51J
receivers was up in the this range. The 51J is advertized in
the 1950 edition of the ARRL Handbook at $875, a veritable
fortune at the time and the SP-600-JX was also up around
$900. However, I think both had a market base in military
sales and civilian sales were just extra. It would be
interesting to know more about the Cardwell receiver.
Evidently it was single conversion which would have put it
at a disadvantage in comparison to the Collins and
Hammarlund products. There is an ad featuring the Cardwell
54 in the 1947 edition of the ARRL Handbook with a fairly
large illustration but I can't tell for certain if its a
drawing or a retouched photo. It might be a photo of a
prototype or possibly a mock-up. If anyone has a Radio's
Master or Allied or other large catalogue of the time please
see if you can find this rx advertised there. I know such an
ad existed but don't know what year. The question, of
course, is whether the receivers were actually available,
the above post, and lack of any actual receivers, suggests
they were not.


--
Richard Knoppow
Los Angeles
WB6KBL

"Richard Knoppow" wrote in message
...

"Alan Douglas" adouglasatgis.net wrote in message
...
I can add some information, based on research done back in 1980 by H.
L. Chadbourne of La Jolla, CA. Quoting from a letter of his to me:

"...I saw the name Ray Morehouse with call letters attached to one of
these ads [the QST ads] , so I looked him up in a recent callbook and
wrote him. Had a very nice letter back. He'd worked for Cardwell from
1924-1947. He had a little on the receiver, but referred me to Moe
Joffe in Los Angeles for more. Moe was directly in on the project.

...Allen D. Cardwell...toward the war's end...wanted to broaden the
product line. He talked with Grenby Mfg. Co. of Plainview, CT about
some sort of joint venture, with Cardwell doing R&D and Grenby as the
manufacturing arm. Grenby had started in 1940 and during WWII made
mainly parts for Pratt & Whitney. It was a sort of machine shop
operation. However at one point Lockheed gave them an electronic
assembly to make, and they liked the work, so decided on it for
postwar. Hence the Cardwell discussions. But the two firms could not
reach agreement and the talks ended by Grenby buying out Cardwell and
moving the firm to Plainville. Mack C. Jones, who had been an
engineer with Raytheon during WWII, was hired by Grenby as Ch.
Engineer, and he suggested the 54 receiver project. Moe Joffe was
under him.

"I had a fine phone conversation with Joffe and hope some time to
interview him in person. He said the 54 was a very advanced set, but
was not put into production because of its extremely high cost, $700 -
$800 a unit. The market did not seem to be there at the
time--possibly again, the huge supply of surplus put a damper on new
sales. Joffe eventually went on to Squires-Sanders and their
communications receiver projects."

I have Morehouse's letter here also; he said he didn't know what
became of the 54 prototype.

Alan

Very interesting and more than is known about some other projects.
Note that the cost of the SP-600 and 51J receivers was up in the this
range. The 51J is advertized in the 1950 edition of the ARRL Handbook at
$875, a veritable fortune at the time and the SP-600-JX was also up around
$900. However, I think both had a market base in military sales and
civilian sales were just extra. It would be interesting to know more about
the Cardwell receiver. Evidently it was single conversion which would have
put it at a disadvantage in comparison to the Collins and Hammarlund
products. There is an ad featuring the Cardwell 54 in the 1947 edition of
the ARRL Handbook with a fairly large illustration but I can't tell for
certain if its a drawing or a retouched photo. It might be a photo of a
prototype or possibly a mock-up. If anyone has a Radio's Master or Allied
or other large catalogue of the time please see if you can find this rx
advertised there. I know such an ad existed but don't know what year. The
question, of course, is whether the receivers were actually available, the
above post, and lack of any actual receivers, suggests they were not.


--
Richard Knoppow
Los Angeles
WB6KBL

Do any of you guys know the SP400? I had one in the sixties. Nice glow to
the meter!

"MoiInAust" wrote in message
...

Lots of snipping here, very long quoted thread.....

Do any of you guys know the SP400? I had one in the
sixties. Nice glow to the meter!
I am more familiar with its predecessor the SP-200 and
210. The SP-400 is essentially identical except it covers
the range of 540Khz to 32Mhz rather than the 2:1 frequency
range bands of the earlier models. It contains the broadened
out RF stages for the broadcast band of the standard SP-200
and the shunt-fed RF of the high frequency model that went
to 40Mhz. Shunt feeding the RF makes it slightly more
selective which is desirable for reducing image response in
the highest band. Otherwise the 400 is the same receiver. At
the time the 200 was made it was probably the best receiver
on the market. I used a BC-779 version as my original
station receiver. I modified it to use an electron coupled
LO with voltage regulation. I later returned it to the
original configuration and found that the RF gain or AVC
would cause serious freqency pulling. The cure for this is a
voltage regulator. The ECO can be made to stay put despite
considerable variation of B+ and filiment voltages but it
had too low an output and loaded the tuning circuit
differently than the original causing some innacuracy in
calibration. I think a regulator on the LO and possibly on
the mixer screen will fix the voltage drift in these guys.
Otherwise they are very nice. Hammarlund had a patent on the
type of crystal filter used in their receivers. The
Hammarlund filter does not detune when the phasing control
is adjusted and has a much wider range of bandwidth than the
original Lamb type filter used by National and
Hallicrafters.


--
---
Richard Knoppow
Los Angeles, CA, USA