[ARC5] FW: Q-5er

[D C *Mac* Macdonald]

One more thing. The Q-multiplier (QF-1 by Heathkit)
and others also offered a notch capability to null
out an interfering carrier OR peak the desired signal.
 
I did NOT use a Q-Multiplier with that old RCA radio,
but simply induced regeneration (controlled by a pot)
to improve the overall selectivity. No notch function
with that. A Heathkit QF-1 came later to use with a
Hallicrafter S-20R and then an S-40.
 
 
* * * * * * * * * * *
* 73 - Mac, K2GKK/5 *
* (Since 30 Nov 53) *
* Oklahoma City, OK *
* USAF, Ret (61-81) *
* * * * * * * * * * *

 

----------------------------------------
From: k2gkk at hotmail.com
To: jfor at quik.com; wrcromwell at gmail.com
Date: Sun, 6 Mar 2011 14:33:45 -0600
CC: arc5 at mailman.qth.net
Subject: Re: [ARC5] Q-5er

The Q-Muiltiplier introduced regeneration
into the last I.F. amplifier which greatly
improved selectivity. If the regeneration
were increased far enough, the I.F. stage
would go into oscillation which could give
the means to copy ICW on a receiver without
a BFO. Hammarlund used that shortcut on the
HQ-100 receiver.

I did it to an old RCA Model 10K 1930s multi
band console radio to use as a ham receiver.
Later I added a Morrow 5BR-1 converter to the
RCA to get much better higher band sensitivity.
That was my station receiver for several years.

* * * * * * * * * * *
* 73 - Mac, K2GKK/5 *
* (Since 30 Nov 53) *
* Oklahoma City, OK *
* USAF, Ret (61-81) *
* * * * * * * * * * *



----------------------------------------
Date: Sun, 6 Mar 2011 12:25:36 -0800
From: jfor at quik.com
To: wrcromwell at gmail.com
CC: arc5 at mailman.qth.net
Subject: Re: [ARC5] Q-5er

Thanks Mac.

-----
A Q multiplier was a posttive FB scheme to narrow IF bandwiths, hence
selectivity of the radio.

Using a second conversion, as by hooking up a 0.190 to 0.550 MHz SARC=-5,
does functionally the same thing.

Hence my question.

Best,

-John

================


Hi Ken,

I vaguely remember something about a signal report of Q5 or some such
thing that meant a good copy. That might not be quite right or
completely wrong. But the Q5ers I have and others I know about don't
have a Q multiplier involved so that might not be right, too. Maybe
earlier "Q5ers" did use a Q multiplier - before there were R-23 radios.

Any help here?

73,
Bill KU8H