[Collins] 51J4 vs 75A3?

[Christopher J Galbraith]

Hi Eugene,

I've been meaning to respond to this, and wanted to give you my experience.

I really like using my 75A-2 on SSB.  I am lucky to have found a product
detector that plugs into the NBFM accessory octal socket on the 'A2, and it
works very well on SSB.  You can find these around for $100-200, get a
Central Electronics Sideband Slicer model (an external unit), or build your
own.  There have been a few articles over the years, one of which I know
appeared in a late 1960s CQ.  You can also download the manual and schematic
to the Universal model here: 

http://tinyurl.com/ydecue

Note that the schematic is cut off at the bottom, but all of the connections
not visible are wired to ground.

I have owned a 75A-4 and a couple 75A-2s, but never a 75A-3.  In fact, I
wanted a 75A-2 because I wanted a receiver that excelled in audio quality
(and thus a wider IF) for AM and some SSB use, rather than the sharp
selectivity given by mechanical filters.  I find that the 75A-2's
transformer-coupled IF selectivity is perfectly adequate for SSB in nearly
all casual listening conditions (no Sweepstakes, etc.) and very nice in AM.
In some ways, I prefer the 75A-2 to the 75A-4, such as in control layout,
quick band scanning, and no need for additional filters.  I also like it on
CW.

So, if I had the money, I would have both a 75A-2 ($300-500) and a 75A-4
with 500 Hz, 3.1 kHz, and 6.0 kHz mechanical filters ($1000-2000).  But, if
I wanted to spend less than $500 on a receiver for AM and SSB, one of my
first choices would be a 75A-2 with a product detector.  (Aside, I am also a
big fan of the Drake R-4, R-4A, and 2-B.)

73, Chris KA8WFC


-----Original Message-----
From: collins-bounces at mailman.qth.net
[mailto:collins-bounces at mailman.qth.net] On Behalf Of ehertz
Sent: Thursday, February 15, 2007 6:58 AM
To: Dr. Gerald N. Johnson; collins at mailman.qth.net
Subject: Re: [Collins] 51J4 vs 75A3?

Hello! thanks to everyone for all the responses. I am unlikely to be able to
afford an A4 anytime soon, unfortunately. I was wondering if you had an
opinion as to whether an A3 with a product detector and agc mod would be any
"worse" of a ham receiver than the J4 with the prod detector/agc mod (dallas
lankford)? 
I've been satisfied with the J4 but the bandswitching is killing me. If a
modified A3 could perform at least as well as the J4 then it could be a good
replacement for the J4 in my operating position.  However, if the opinion is
that the J4 is better than the A3, I would likely stick with the J4.
Thanks again to everyone
Eugene

>-----Original Message-----
>From: Dr. Gerald N. Johnson [mailto:g369n792j at ispwest.com]
>Sent: Tuesday, February 13, 2007 12:03 PM
>To: collins at mailman.qth.net
>Subject: Re: [Collins] 51J4 vs 75A3?
>
>On Mon, 2007-02-12 at 18:15 -0600, Joe Eide wrote: 
>> Well Eugene, I can give you a few differences and opinions that probably 
>> don't mean much, but will give you something to think about anyway: 
>> 



______________________________________________________________
Collins mailing list
Home: http://mailman.qth.net/mailman/listinfo/collins
Help: http://mailman.qth.net/mmfaq.html
Post: mailto:Collins at mailman.qth.net