Re: Receive only version?

Bob, N1KPR

I have not actually spec'd out the receiver yet, but can tell you that it is very sensitive and the MDS is excellent...guessing about -130dB. The one (of many) receiver controls missing is AGC for general SWLing. If I was going to build one for receive-only, I'd cut the 12V T/R relay rail and add an audio leveler to act as AGC (link below). Another definite addition would be a real RF Gain control. I'm using a 5K pot as an attenuator in the front end. And, of course, all receivers need an S-Meter. It would be a fun project for an SWLer who has some tech skills. Half the fun is building this stuff.

Go to the 3-minute mark to see the leveler

and the complete system here:

Gud signals to all,
Bob, N1KPR

NOTE Pls add backup address to your phone book: rwbetts@...


Engineering: Where Enigma meets Paradox

On Wednesday, September 2, 2020, 8:08:08 AM EDT, Bill Cromwell <wrcromwell@...> wrote:

Hi Gerald,

Your idea really is practical. To assure your radio does not transmit
you can disconnect the CW key line and the Push to talk. You could go so
far as removing the finals but just turning the bias and drive pots all
the way down should be good - just in case it does get put into
transmit. Some day you may want to sell it to a licensed ham (or get
your own ham license). All you have to do is connect those CW and PTT
lines and set up the bias and drive.

The fact is - I do a lot more listening than transmitting even though I
am licensed. I already have a general coverage receiver but I also use
my V3 for SWL. I also use it as a signal tracer and heterodyne frequency
meter on my bench. You do not have to transmit to get some work out the


BillĀ  KU8H

bark less - wag more

On 9/2/20 7:46 AM, Gerald Bramwell wrote:
> Hi all,
> As a SWL for a number of years and haveing found this group, I was
> wondering if a receive only version could be built as it looks like a
> very interesting project.
> 73s
> Gerald Bramwell (RS49875)

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