[Boatanchors] difference bet. 75A3 and A4?

[Jim Wilhite]

Todd I recently picked up an A2 and have a question about it versus the A1. 
In your answer to Gene, you stated the A1 had better audio than the A2.

I wonder to what the difference in the audio was attributed?  My A2 has had 
the IF section narrowed according to the book and is pretty narrow compared 
to other receivers I own.  The manual for the A2 says the conversion will 
produce 2.4 kc at 6 db down.

That is equivalent to most transceivers of the late 60s and 70s designed for 
SSB.  Needless to say, this makes any AM signal pretty crappy, but 
converting to broadband  gives 4 kc at 6 db.

Anyway, I don't have an A1 manual to look at and am curious from someone 
that knows.  Might it be a good thing to remove the narrow band conversion 
and look at converting the audio section to resemble the A1?

73  Jim
W5JO
.
>
> Eugene -
>
> Let's see if this one makes it to the list, my last post about Beckman
> was bounced back.
>
> The mechanical filters actually work only to narrow things in noisey
> conditions. The 75A-4 actually has a product detector for SSB
> reception. While the A-2 and A-3 are basically identical (except the
> A-3 having 2 mechanical filters which could be retrofit to the A-2),
> the A-4 is a 'new' receiver in comparison. The main difference is that
> the 75A-4 was designed for SSB operation with the associated
> refinements. Even the cabinet design is completely different, with the
> A-4 cabinet being made up of several pieces including the front panel.
>
> If you want a more traditional AM/CW receiver, stick with the A-3 or
> even get the A-2 and avoid the mechanical filters altogether. If you
> want the SSB option along with reasonably decent AM and CW with the
> ability to narrow things down to 500cps (with CW filter), the 75A-4 is
> tough to beat. And although 6kcs was the best you could do for AM,
> there is now an aftermarket filter available for 9kcs to broaden
> things out a bit more. You can tune SSB with the A-3, but not as
> easily. And there's also the passband tuning system on the A-4, which
> is very ingenious and fun to play with.
>
> As far as price, a 75A-4 will set you back at least twice as much as
> the earlier models if you shop online, depending on condition and
> optional filters installed.
>
> My choice would be for the 75A-1 with its nifty band-in-use lighted
> dial and very good audio. Tunes SSB amazing well too even though it
> has no prod det. Doesn't cover 160, though.
>
> de Todd/'Boomer'  KA1KAQ