Tuesday, June 08, 2010

Another K3 panadapter option?

Cross Country Wireless recently introduced a new product, a built, boxed and ready to use SDR receiver that is optimized to work with the bog standard sound card provided with every computer. It covers two 48kHz segments which may be on one or two bands using a switched local oscillator. At £49.95 it looks like something of a bargain.

I was looking at the product's web page this evening and the thought occurred to me that this might make a rather good inexpensive option for a panadapter for the Elecraft K3. It would need a different crystal to cover the K3 IF output frequency which is 8.215MHz, but that shouldn't be a problem. CCW might even offer this as a stock option if there was a demand for it.

As the receiver covers 40m and 30m everything else should work OK unmodified. The key point would be whether there is adequate isolation to prevent the local oscillator leaking into the K3 IF and desensitizing the receiver - the reason why most people use a buffer amplifier when using SoftRock boards for this purpose.

I don't have a great urge to have a panadapter display and I already have three sound cards (well, one and two USB sound modules) in use with my shack computer so this isn't something I'm planning on trying. But I thought it might be worth mentioning the possibility for other K3 users. Even if the idea is a non-runner, the Cross Country Wireless receiver still looks like a very nice product.


LY2SS said...

Hi Julian,
Have you seen these?

g4ilo said...

No. It looks a bit more sophisticated than the CCW SDR so perhaps a bit wasted as a panadapter. Useful link, though. Thanks for posting it, I'm sure others will be interested.

LY2SS said...

I've already assembled lite version.
It has _very_ interesting multiplication chip in it - ICS512M - you must see it's datasheet. (Dunno if it's available in EU)
I should thank you because you helped me to buy qrp crystals in ebay - they fit lite rx very well ;-)
Regarding lite rx itself - mixed feelings.
Potential, ideas (and price too!) are _great_, but so far sensitivity is quite poor. Don't know what to blame for - poor soundcard or...