on start up spectrum has a pattern of up and down peaks

N4AB

6700 with GPSDO using Win 7 On start up I sometime get a spectrum that I don't know what it is or even know how to describe. It starts with a normal spectrum an slowly changes to this up and down peak and valley spectrum, 10 to 12 db swing and every 15 kHz (on 20 meter band). It lasts for 5 minutes to 30 minutes ( if I don't restart SmartSDR ) then slowly goes away. If I do a re-start, most of the time it "cures" the problem and everything is fine for the rest of the day. It does not happen every time but enough that it is a problem. This morning it lasted a little over 30 minutes and I was able to get a screen shot of the spectrum. Now if I can figure out how to send the picture. I hope this works. Tnx Al N4AB

philip.theis

Does it stay the same if you change bands? Do you have antenna attached?

Ed, K0KC

This looks like what I see on 160 meters which I traced to my cable modem. With my Flex-5000, I had to power-down the modem to make contacts, but I just realized that I cannot do that with the 6700 unless I make a direct connection to the computer rather than running it over the LAN. Let me think about this...maybe the LAN will work without an Internet connection if I just leave the router on.

N4AB

Yes, I have the antenna switched on at the external antenna switch, it is usually grounded but when I get this problem the antenna has been active. And the problem also follows band changing by using the band switch or by just entering a new frequency/band on the slice control panel. Tnx Al N4AB