Hi, I have got Basic RX and Basic TX daughterboards. But i have no antennas for them as they are not provided with these daughterboards by the ettus corp. No reference at ettus.com's sales page either. While running usrp_wfm_rcv.py, i hear a very faint voice of the fm channel when using a 1 foot piece of copper wire. How can I get clear signals? Are there any antennas for these daughterboards? Secondly, is connecting wire as antenna safe? Are there any safety precautions to be taken e.g. using anti static straps? Thanks
on 2008-11-22 13:38
on 2008-11-25 14:55
Hi (1) I use the same daughterboards. It's difficult to buy antennas. Maybe you can buy some antennas in "radio store" and use F-SMA. (2) I don't know the second question. CJay ali siddiqi wrote: > Hi, > > I have got Basic RX and Basic TX daughterboards. But i have no antennas > for > them as they are not provided with these daughterboards by the ettus > corp. > when using a 1 foot piece of copper wire. > How can I get clear signals? Are there any antennas for these > daughterboards? > > > Secondly, is connecting wire as antenna safe? > Are there any safety precautions to be taken e.g. using anti static > straps? > > Thanks
on 2008-11-26 09:40
Hi, I just received my USRP today (thanks Ettus!) and am in a similar position, wanting to smoke test by FM demod. I probably have more or less the same antenna as you. I cut in half a 1M SMA pigtail I had lying around and soldered 2M of wire out of an Ethernet cable to the centre conductor. It receives strong FM stations just fine. I know this antenna is at least some use because when I unplug it I can't hear FM stations anymore. Mine is duct-taped to the ceiling. First, just to be sure: are you sure your volume is turned up? ;) I used alsamixer and turned master and PCM right up, then turned up volume in the app. If the station is just quiet (no hiss/crackle/noise) then this might be your problem. Or perhaps your speakers are wimpy and you need headphones. Second, what can you see in usrp_fft.py (or the wfm app) for the station you're trying to recieve? With the basicrx I see a fairly obvious peak about 25db above noise when tuned to a strong local FM station. I would also recommend you try the TVRX daughterboard if you have one. I am obviously new to g-r, and would love to hear what external RF hardware (antennas? preamps? external radios with IF outputs?) others are using, regardless of application. I have been lurking in the list for a while and searched the archives a bit, but there does not seem to be much discussion of the subject. > Secondly, is connecting wire as antenna safe? > Are there any safety precautions to be taken e.g. using anti static straps? I think you can get away with it, with a few caveats. Don't short anything, get struck by lightning, stick it in a microwave oven, trip over it, etc. I have been swapping the antenna around with the USRP powered on. Having now thought about it, I probably shouldn't be so cavalier. Regards, Blair.