[Heathkit] Audio filter on HR-10B

[Jim Shorney]

On Tue, 04 Jul 2006 16:44:30 -0400, Harry Vaught, KT4AE wrote:

>I have a couple of the Radio Shack DSP-40's.  One is on my SX-101A and 
>the other on the SX-117.  They give a range of sharp cutoff bandwidths 
>much more useful than those on the receivers.  They come in very handy 
>in SSB and CW.  They're discontinued and I bought mine at clearance 
>prices.  I see them all the time at hamfests.
>
>They're called DSP's, but I don't know how much DSP'ing they do. 
>They're not much for noise reduction, but are good audio filters.


I love DSP40s. They do exactly what the claim to do - reduce noise. The auto
notch works fairly well, too. I've got three of them, and yes, they are a DSP
based noise reduction system. A lot of people were disappointed in them
because they expected them to perform like a $300 DSP unit - which they were
not. They do, however, perform like a $70 (original list price) DSP unit, so
it's all a matter of expectations. Any time I see one at a flea market for a
reasonable price, I snatch it up. They're great for vintage rigs, I used to
use one all the time for RS satellite reception on 10 meters with my TR7.

BTW, there is a mod on mods.dk to increase the output level from the
headphone jack. I haven't tried it yet. I've been toying with the idea of
adding input AGC as well, but haven't gotten a round tuit yet....

73

-Jim

-- 
Jim Shorney      -->.<--Put complaints in this box
jshorney (at) inebraska.com
Ham Radio NU0C
Lincoln, NE, USA
EN10ps
http://incolor.inetnebr.com/jshorney/