[R-390] Best approach for SSB mod on R-390A

[2002tii]

Cecil wrote:

>I think Ten-Tec uses a DSP implementation in the RX-340 and 350.
>Les can report on both as he has owned each and still has one.

I have an RX340, and the synchronous detector is -- IMO -- all but 
useless.  The WJ-8711 implementation is a tiny bit better, but also 
-- IMO -- useless.

I have heard from other sources what Les reported -- that SAM in the 
RX350 is better than the 340 -- but have not had the chance to play 
with one.  (I see that not everyone thinks the 350 SAM is great -- 
some of the eHam.net reviewers give it low marks, for example.)

With the 340, besides losing lock all the time, accompanied by 
distracting clicks, a number of the other features don't work with 
SAM on -- no notch filter or PBT, and the BW choices are limited 
to >= 4000 Hz.  So, even if it held lock properly, it would still be 
pretty useless because the very signals where you really need SAM are 
the most likely to require the other tools, too.  I assume the DSP 
just lacks the horsepower to run all the routines simultaneously, but 
I don't know for sure.

The blurb at the Ten-Tec website indicates that the RX350 lets you 
use PBT, notch filter, and narrow BWs, and allows you to select 
sidebands, with SAM on.  I don't know if you can also use SAM to hear 
both sidebands (DSB), as you can on the 340 and R8B.  (This feature 
can be useful to reduce atmospheric noise if neither sideband has 
interference.)

Best regards,

Don