FA: HAMMARLUND SP-400 Receiver
 

Sold from 1946 * 1948.
Good condition.

http://cgi.ebay.com/ws/eBayISAPI.dll...9134&ssPa geN
ame=STRK:MESE:IT&ih=005

Thanks,
Steve

HAMMARLUND SP-400 Receiver
 

"North Lake Audio" wrote in message
...
Sold from 1946 * 1948.
Good condition.

http://cgi.ebay.com/ws/eBayISAPI.dll...9134&ssPa geN
ame=STRK:MESE:IT&ih=005

Thanks,
Steve


This is NOT a Super-Pro 400, it is an earlier receiver,
looks like military surplus SP-200. The exact model depends
on the frequency range. The missing label on the front was
the military identifier. Three frequency ranges were offered
535KC to 20Mc (standard) 1250 KC to 40 Mc, and a version
covering 100kc to 400Kc on the two lower bands and 2.5 mc to
20Mc on the upper three. There is a fair amount of material
on the web which will alow identifying the particular model.
If the original bottom cover is present it may have a
schematic diagram pasted to the inside which will also
identify the model. A large number of these receivers were
built under contract by Howard Radio Co. The SP-200 series
was replace by the SP-400 in 1946. The SP-400 has continuous
coverage from 535Khz to 32Mhz. In addition, the band
indication is engraved or printed on the front panel rather
than on the skirt of the bandswitch knob. I wonder if the
power supply is around someplace. They are not impossible to
build but the original would be nice. Most military
receivers came with rack mount supplies.


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

HAMMARLUND SP-400 Receiver
 

BC 779


"Richard Knoppow" wrote in message
link.net...

"North Lake Audio" wrote in message
...
Sold from 1946 * 1948.
Good condition.

http://cgi.ebay.com/ws/eBayISAPI.dll...9134&ssPa geN
ame=STRK:MESE:IT&ih=005

Thanks,
Steve


This is NOT a Super-Pro 400, it is an earlier receiver, looks like
military surplus SP-200. The exact model depends on the frequency range.
The missing label on the front was the military identifier. Three
frequency ranges were offered 535KC to 20Mc (standard) 1250 KC to 40 Mc,
and a version covering 100kc to 400Kc on the two lower bands and 2.5 mc to
20Mc on the upper three. There is a fair amount of material on the web
which will alow identifying the particular model. If the original bottom
cover is present it may have a schematic diagram pasted to the inside
which will also identify the model. A large number of these receivers were
built under contract by Howard Radio Co. The SP-200 series was replace by
the SP-400 in 1946. The SP-400 has continuous coverage from 535Khz to
32Mhz. In addition, the band indication is engraved or printed on the
front panel rather than on the skirt of the bandswitch knob. I wonder if
the power supply is around someplace. They are not impossible to build but
the original would be nice. Most military receivers came with rack mount
supplies.


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

HAMMARLUND SP-400 Receiver
 

Richard Knoppow wrote:
"North Lake Audio" wrote in message
...
Sold from 1946 * 1948.
Good condition.

http://cgi.ebay.com/ws/eBayISAPI.dll...9134&ssPa geN
ame=STRK:MESE:IT&ih=005

Thanks,
Steve


This is NOT a Super-Pro 400, it is an earlier receiver,
looks like military surplus SP-200. The exact model depends
on the frequency range. The missing label on the front was
the military identifier. Three frequency ranges were offered
535KC to 20Mc (standard) 1250 KC to 40 Mc, and a version
covering 100kc to 400Kc on the two lower bands and 2.5 mc to
20Mc on the upper three. There is a fair amount of material
on the web which will alow identifying the particular model.
If the original bottom cover is present it may have a
schematic diagram pasted to the inside which will also
identify the model. A large number of these receivers were
built under contract by Howard Radio Co. The SP-200 series
was replace by the SP-400 in 1946. The SP-400 has continuous
coverage from 535Khz to 32Mhz. In addition, the band
indication is engraved or printed on the front panel rather
than on the skirt of the bandswitch knob. I wonder if the
power supply is around someplace. They are not impossible to
build but the original would be nice. Most military
receivers came with rack mount supplies.


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


The SP-400-X coverage was from 540 kc to 30 mc. The SP-400-SX covered
1250 kc to 40 mc. Those were the only two variants.

But, you are correct on the bandswitch and panel engravings.

Just wanted to set the record straight.

H. State

HAMMARLUND SP-400 Receiver
 

"Harold" wrote in message
ups.com...

Richard Knoppow wrote:
"North Lake Audio" wrote in
message
...
Sold from 1946 * 1948.
Good condition.

http://cgi.ebay.com/ws/eBayISAPI.dll...9134&ssPa geN
ame=STRK:MESE:IT&ih=005

Thanks,
Steve


This is NOT a Super-Pro 400, it is an earlier receiver,
looks like military surplus SP-200. The exact model
depends
on the frequency range. The missing label on the front was
the military identifier. Three frequency ranges were
offered
535KC to 20Mc (standard) 1250 KC to 40 Mc, and a version
covering 100kc to 400Kc on the two lower bands and 2.5 mc
to
20Mc on the upper three. There is a fair amount of
material
on the web which will alow identifying the particular
model.
If the original bottom cover is present it may have a
schematic diagram pasted to the inside which will also
identify the model. A large number of these receivers were
built under contract by Howard Radio Co. The SP-200 series
was replace by the SP-400 in 1946. The SP-400 has
continuous
coverage from 535Khz to 32Mhz. In addition, the band
indication is engraved or printed on the front panel
rather
than on the skirt of the bandswitch knob. I wonder if the
power supply is around someplace. They are not impossible
to
build but the original would be nice. Most military
receivers came with rack mount supplies.


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


The SP-400-X coverage was from 540 kc to 30 mc. The
SP-400-SX covered
1250 kc to 40 mc. Those were the only two variants.

But, you are correct on the bandswitch and panel engravings.

Just wanted to set the record straight.

H. State

I've never seen an SP-400-SX, there certainly was an
SP-200 with this coverage. It differed from the others in
having shunt-fed RF plate coils rather than series fed. This
resulted in somewhat sharper tuning of the RF stages and
lower image response. I am not sure if the same arrangement
was used for either SP-400 models. These are still very
respectable receivers.


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

HAMMARLUND SP-400 Receiver
 

Richard Knoppow wrote:
I've never seen an SP-400-SX, there certainly was an
SP-200 with this coverage. It differed from the others in
having shunt-fed RF plate coils rather than series fed. This
resulted in somewhat sharper tuning of the RF stages and
lower image response. I am not sure if the same arrangement
was used for either SP-400 models. These are still very
respectable receivers.
---
Richard Knoppow
Los Angeles, CA, USA


There's a 400-SX on ebay right now. As a major Hammarlund fan, I'm
tempted, but only mildly. It's been considerably modified, and by the
time packing fees and shipping are added to the BIN figure or something
close to it, we're in SP-600 territory. It's at
http://cgi.ebay.com/ws/eBayISAPI.dll...MEWA%3AIT&rd=1.

HAMMARLUND SP-400 Receiver
 

"Avery W3AVE" wrote in message
ups.com...

Richard Knoppow wrote:
I've never seen an SP-400-SX, there certainly was an
SP-200 with this coverage. It differed from the others in
having shunt-fed RF plate coils rather than series fed.
This
resulted in somewhat sharper tuning of the RF stages and
lower image response. I am not sure if the same
arrangement
was used for either SP-400 models. These are still very
respectable receivers.
---
Richard Knoppow
Los Angeles, CA, USA


There's a 400-SX on ebay right now. As a major Hammarlund
fan, I'm
tempted, but only mildly. It's been considerably modified,
and by the
time packing fees and shipping are added to the BIN figure
or something
close to it, we're in SP-600 territory. It's at
http://cgi.ebay.com/ws/eBayISAPI.dll...MEWA%3AIT&rd=1.


I am also skeptical about home made modifications. Its
easy to get the AVC unbalanced and create other problems.
My BC-779, bought surplus some 40 years ago, was heavily
modified to follow circuits published in CQ magazine. After
experimenting with these and my own modifications I restored
the original circuits and found they performed just about as
well, plus I eliminated some circuit loading of the RF tuned
circuits. The original uses what today would be considered
quite noisy tubes but one must take into account the
naturally occuring noise in the HF communication bands. Its
quite high so often a front end which is very quiet does not
buy much. Better to have one which can take overload. The
one worthwhile modification I've found for the SP-200 series
is the use of regulated voltage on the local oscillator and
mixer screen. This eliminates the frequency variation when
the RF gain changes.


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

HAMMARLUND SP-400 Receiver
 

Our reaction apparently was universal. The highest of three bids was a
little over $27. Needless to say, that did not meet the reserve.