I'm interested in Hammarlund's receivers, but I know very little about the
various models in between the HQ-129X and the HQ-110/170/180's that (I
thought) ended the line.

Is there a comprehensive list of the various Hammarlund models, showing
their capabilities, produciton dates, and specs?

I'm not looking for engineering drawings, but if some posts an HQ-150, I'd
like to know what it's capable of.

TIA.

Bill Warren

(Email address is anti-spammed.)

In article 6X84c.12172$mM.93168@attbi_s02,
"William Warren" wrote:

I'm interested in Hammarlund's receivers, but I know very little about the
various models in between the HQ-129X and the HQ-110/170/180's that (I
thought) ended the line.

Is there a comprehensive list of the various Hammarlund models, showing
their capabilities, produciton dates, and specs?

I'm not looking for engineering drawings, but if some posts an HQ-150, I'd
like to know what it's capable of.

TIA.

Bill Warren

(Email address is anti-spammed.)



This url, for "Favorite SW Tube Receivers", gives the basic specs on
several Hammarlunds:

http://www.dxing.com/rx/tindex.htm

--
"Everything that rises must converge"
--Flannery O'Connor

In article 6X84c.12172$mM.93168@attbi_s02, "William Warren"
writes:

I'm interested in Hammarlund's receivers, but I know very little about the
various models in between the HQ-129X and the HQ-110/170/180's that (I
thought) ended the line.

I wish someone would do a Hammarlund book, like what Chuck Dachis did for
Hallicrafters. Yes, the HQ-170/180 pretty much ended the line, along with the
Super Pro 600, though there was a solid-state HQ-215, that didn't look much
like a Hammarlund.

Is there a comprehensive list of the various Hammarlund models, showing
their capabilities, produciton dates, and specs?
I'm not looking for engineering drawings, but if some posts an HQ-150, I'd
like to know what it's capable of.

Your best bet is the book on all makes, "Shortwave Receiver Past & Present" by
Fred Osterman. It has a capsule history of all major makers and detailed
descriptions (features and tube lineup and functions) for every model. The
Hammarlund chapter is 12 pages. But the book covers only back to 1945.

For the HQ-120 and 129X, get "Communications Receivers: The Vacuum Tube Era" by
Raymond S. Moore. It's just as good in most ways, better in terms of odd
models, and goes back to 1932 (Comet Pro). 13 pages of Hammarlund.

Either book will give you frequency band coverage, dual conversion, selectivity
controls, and the like. Osterman's gives published specs like sensitivity.

National could use a good book too. Of course the above two books cover
National, Halli, etc. just as well as Hammers. --Mike K.



Oscar loves trash, but hates Spam! Delete him to reply to me.

William Warren wrote:
I'm interested in Hammarlund's receivers, but I know very little
about the various models in between the HQ-129X and the
HQ-110/170/180's that (I thought) ended the line.

Is there a comprehensive list of the various Hammarlund models,
showing their capabilities, produciton dates, and specs?

I'm not looking for engineering drawings, but if some posts an
HQ-150, I'd like to know what it's capable of.

TIA.

Bill Warren

(Email address is anti-spammed.)

William:
See: http://www.hammarlund.info/ which is the home page of the Hammarlund
Historian!
BTW, I have a wonderful HQ-150.
--
Brian Denley
http://home.comcast.net/~b.denley/index.html

"Brian Denley" wrote in message
news:WCa4c.11250$i76.191312@attbi_s03...
William Warren wrote:
I'm interested in Hammarlund's receivers, but I know very little
about the various models in between the HQ-129X and the
HQ-110/170/180's that (I thought) ended the line.

Is there a comprehensive list of the various Hammarlund models,
showing their capabilities, produciton dates, and specs?
[snip]

William:
See: http://www.hammarlund.info/ which is the home page of the Hammarlund
Historian!

BTW, I have a wonderful HQ-150.
--
Brian Denley
http://home.comcast.net/~b.denley/index.html

Thanks to all those who replied: the links have answered my questions and
will provide a good reference source.

Brian, since the HQ-150 is single-conversion, how well does it handle
image-rejection? Is the Q-multiplier "reject" feature useful there?

TIA.

Bill

William Warren wrote:
"Brian Denley" wrote in message
news:WCa4c.11250$i76.191312@attbi_s03...

William Warren wrote:

I'm interested in Hammarlund's receivers, but I know very little
about the various models in between the HQ-129X and the
HQ-110/170/180's that (I thought) ended the line.

Is there a comprehensive list of the various Hammarlund models,
showing their capabilities, produciton dates, and specs?

[snip]

William:
See: http://www.hammarlund.info/ which is the home page of the Hammarlund
Historian!

BTW, I have a wonderful HQ-150.
--
Brian Denley
http://home.comcast.net/~b.denley/index.html


Thanks to all those who replied: the links have answered my questions and
will provide a good reference source.

Brian, since the HQ-150 is single-conversion, how well does it handle
image-rejection? Is the Q-multiplier "reject" feature useful there?

TIA.

Bill


The Q-multiplier can be used to reject any single undesired signal. It
would be as effective on an image as anything else. Problem is that if
it is occupied taking out an image then it can't be used to take out
another undesired signal.
Single conversion is not always a kiss-of-death. The real question is
how selective is the front end. If its sharp enough then images will be
supressed. After all thats where image rejection is done in any radio.

-Bill M

"William Warren" ) writes:
"Brian Denley" wrote in message
news:WCa4c.11250$i76.191312@attbi_s03...
William Warren wrote:
I'm interested in Hammarlund's receivers, but I know very little
about the various models in between the HQ-129X and the
HQ-110/170/180's that (I thought) ended the line.

Is there a comprehensive list of the various Hammarlund models,
showing their capabilities, produciton dates, and specs?
[snip]

William:
See: http://www.hammarlund.info/ which is the home page of the Hammarlund
Historian!

BTW, I have a wonderful HQ-150.
--
Brian Denley
http://home.comcast.net/~b.denley/index.html

Thanks to all those who replied: the links have answered my questions and
will provide a good reference source.

Brian, since the HQ-150 is single-conversion, how well does it handle
image-rejection? Is the Q-multiplier "reject" feature useful there?

The Q-Multiplier will not do a thing for image rejection. That would
be determined by front end selectivity, and the placement of the IF
frequency in reference to the signal frequency (ie if the IF is low
compared to the signal frequency, then image rejection is lower than
if the IF is high in frequency relative to the signal frequency).

While there was a period in the sixties when there were a fair number
of construction articles that featured front-end Q-multipliers, which
were supposed to improve image rejection (because it improved
front end selectivity), the Q-multiplier in the Hammarlund (and most
or all commercially made receivers) operate at the IF frequency, where
they only affect IF selectivity, not image rejection.

Michael VE2BVW

Bill:
I generally use the HQ-150 above 5 MHz and I haven't had any problems with
images. The 150 circuit is basically the same as the previous single
conversion 'Hammers' and, while a bit drifty for the first 10 minutes or so,
works very well. The receiver can usually hear anything my modern tabletops
can. Selectivity, however, is another issue. Those old xtal filters had
very poor shape factors and the skirt selectivity suffers.

--
Brian Denley
http://home.comcast.net/~b.denley/index.html

"William Warren" wrote in message
news:Qyi4c.15801$Gm5.46188@attbi_s04...

Thanks to all those who replied: the links have answered my questions and
will provide a good reference source.

Brian, since the HQ-150 is single-conversion, how well does it handle
image-rejection? Is the Q-multiplier "reject" feature useful there?

TIA.

Bill

In article ,
(Michael Black) writes:

The Q-Multiplier will not do a thing for image rejection.

Not per se, but it will notch out a het from an image signal just as well as
from a legitimate passband QRM signal. Although image heterodynes do tend to
drift around a lot, making them harder to keep notched out.

FWIW, my HQ-160 has a Q-multiplier that works only to peak desired signals, not
notch out QRM. The passive slot filter does that (same as on the 170/180,
which do not have Q-mults). Maybe the 150 is different.

Anyway, a peaking Q-mult is perfect for CW and nice for SSB, but not much good
for AM.
--Mike K.

Oscar loves trash, but hates Spam! Delete him to reply to me.

Mike Knudsen ) writes:
In article ,
(Michael Black) writes:

The Q-Multiplier will not do a thing for image rejection.

Not per se, but it will notch out a het from an image signal just as well as
from a legitimate passband QRM signal. Although image heterodynes do tend to
drift around a lot, making them harder to keep notched out.

FWIW, my HQ-160 has a Q-multiplier that works only to peak desired signals, not
notch out QRM. The passive slot filter does that (same as on the 170/180,
which do not have Q-mults). Maybe the 150 is different.

Anyway, a peaking Q-mult is perfect for CW and nice for SSB, but not much good
for AM.

But I was making the point that the Q-multiplier has nothing to do
with image rejection.

Your scenario is about treating the image like any unwanted signal, and
notching it out or peaking elsewhere in the receiver's passband. But
surely that only works if you're lucky. An image by definition is
a frequency that translates to the same IF frequency, and there's no
way you can knock out a signal on the image frequency if it ends up
right where your wanted signal is in the IF passband. To knock out one
is to knock out the other. The situation is identical to that in
a direct conversion receiver, where you can get good selectivity with
an AF filter, but it won't do a thing for the audio image, since it's
right there in the passband. You can only get rid of that audio
image by front end selectivity, or phasing.

On a different note, one use for a Q-Multiplier on AM is for
improved exalted carrier reception. The narrow peak works to
boost the carrier in reference to the sidebands, but the skirts
of the Q-Multiplier are relatively weak so it doesn't affect
the sidebands too much. You are in effect regenerating the
carrier, so the distortion seen with fading is reduced. A variant
on "synchronous detectors" but something in place long before such
detectors were practical.

Michael VE2BVW