Sunday, February 03, 2013


I spent all of Saturday monitoring the FreeDV suggested frequencies but so far I haven't heard a thing. I am really surprised. Whenever a new data mode is announced the main problem is usually QRM as too many people pile eagerly on to the recommended frequencies. FreeDV is a development that is potentially as revolutionary for the hobby as the advent of SSB in the 1960s. I would have thought that more hams would want to be in at the start, especially as there is no cost apart from the time taken downloading the software.

Perhaps people just don't know where to go. Since my last post I have discovered the FreeDV QSO Finder. This is a tool to enable potential users of FreeDV to find out where others are. Suggested frequencies are: 14.236, 7.190 and 5.4035, though I've seen people using other frequencies. This weekend's contest will probably put the kibosh on attempts to set up contacts for now, but I hope for better luck next week when the bands are quieter.


Roger G3XBM said...

I must give this a try Julian. Am I right in thinking you need 2 sound cards? Could this be something that puts people off? I have a SignaLink USB - can that be used as a second sound card for this?

Bob G3WKW said...

oh the expense Roger! They cost about 2 pounds post paid. But the cheap ones do not seem to like driving a DC load and don't include a blocking capacitor. I have destroyed 3 this year! Whatever you use for Digital Modes like WSPR should suffice and you just need a headset in addition which could go to your standard PC soundcard, but a USB one is probably more convenient. The software seemed flaky the first couple of times I used it, having to use regedit between uses, but that seems to have inexplicably cleared itself. I spent a lot of time trying to get it working on Raspberry Pi but it is a heavy load and a very inefficient install there. But I can finally get my WSPR up and down from a web interface.

Roger G3XBM said...

Bob, how can they do these for the price INCLUDING postage?

Unknown said...

If you have a SignalLink then you don't really need another sound card, Roger. Your PC has an internal sound card which is connected to speakers already. It also has a mic input which probably isn't used unless you already have a computer mic. So all you need is a microphone - which you may already have.

I'm actually using one of the cheap USB sound dongles mentioned by Bob, which cost less than £2 from Hong Kong using eBay. I already had a mic.

Julian, G4ILO