Re: Receive only version?


Scott McDonald
 

Hi Gerald,

It’s a very doable project if you have a bit of building experience or friends that build.

I got some good receiver building advice from a clever lady named Allison suggesting to break the radio into its parts and build them as 50 ohm blocks that could be built, tested and put together.  They can later be easily swapped out for ones that you like better, like different band pass filters or a decent AM detector.

My receiver is based on Version 3 and has been hot rodded a bit since I first built it, but the basic great Farhan topology remains, and other than adding an IF amplifier with AGC and a cw filter, none of the improvements made a dramatic difference in performance.  The basic design is very good.

If you’re pretty new to this you might consider picking up on old or new uBITX and studying it for a while first, I found that really helpful.  If you just want a good SWL radio for a nice price then the folks that suggest just picking up a stock uBITX have it right.  It would be hard to scratch build one for any less.

If you decide to build one in sections, there are inexpensive boards for things like the mixers (totally homebrew or using a commercial mixer) and post mixer amps (same as the UBITX but easy SMT) available on Osh Park.  And using an inexpensive EBay TDA2050 audio amp kit would provide lots of clean cheap power for only a few quid.

There are a couple pics of my V3 receiver on my QRZ page if interested.

Scott ka9p


On Sep 2, 2020, at 6:46 AM, Gerald Bramwell <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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