DISCLAIMER: I have no association with UVB-76 station, neither do I have any clue what is the content I am relaying. I can only assure, that the signal is received on 4.625MHz AM-modulated 900km NW from supposed origin and retransmitted unaltered. In no way can I guarantee this service, nor be considered responsible of any content re-transmitted. The only purpose for this relay to exist is because lot of people who do not have equipment or are located too far from station seem to be interested about listening to it. Should the UVB-76 station- or transmission content owners feel violated in any way, please contact me at uvb76.repeater@gmail.com and we will work it out.

Note, that because of shortwave radio signal propagation specifics the station can be more or less reliably received from around 4pm to 6am GMT on summertime. It is almost 24h audible during the winter, with short "skip-zone" blank-out around 6pm GMT.

The USB feed is considered as main source of audio today, as the voice messages are much better audible there than on the AM stream. However, the buzzer sound from the AM stream is somewhat more pleasant to listen at, so both feeds are kept simultaneously.

Wednesday, July 21, 2010

Receiver Upgrade for Listening Station!

I am glad to announce, that UVB-76 Internet Repeater has now its dedicated SDR (Software Defined Radio). The receiver is called Soft66lite and the improvement is nothing short of spectacular. It looks like this:

I have used to think that Icom IC-R20 what was used so far is pretty good radio receiver, period. The reason for replacing it was just that I wante to have my scanner back and therefore was looking for inexpensive replacement. The $18 soft66lite was pretty much the only alternative found on eBay and I had no problem having it in kit form. As this is fixed center frequency, the component needed was also a crystal with the frequency close to 4.625MHz. Got 4.608MHz from Elfa, which is good enough for tuning in with 48kHz sample rate soundcard.

I was stunned to find out, that the $18 receiver did way better than Icom had ever done with weak receptions! I am running it with ordinary long aerial of about 10 meters and as of 6pm GMT, Icom hears nothing with its magnetic loop, when SDR has audible signal. When I use Icom with aerial, the RF stage overloads from noise.

The station uses WinradHD as SDR software for tuning in and demodulating the signal. Despite some quirks on soundcard handling, it seems to be the most straightforward SDR software today. The screenshot looks like this:

So, as of now, the setup for monitoring station looks like this:

10m aerial antenna -> Soft66lite SDR -> Computer with Behringer BCD3000 -> WinradHD Software -> Virtual Audio Cable -> Edcast Standalone -> uk3-pn.mixstream.net

Happy Listening!

1 comment:

  1. I just wanted to say thanks for the feed and for sharing your setup. It's all pretty cool!