Unidentified signal at 120 mhz

[sumanta39]

Hi guys,

So I was playing with a rtl sdr dongle lately and came across a strange signal exactly at 120 mhz. I am using gqrx for sdr side. Any idea what it is? Here is the gps info of my location if relevant:

Latitude:31.70677465 N
Longitude:76.52492523 E
Sea level: 882 M

 

[moonbounce]

Just a thought, try switching to WFM and see if you hear anything, it looks like an FM signal?

 

[DaveNF2G]

Does it seem to be modulated or just a "dead carrier" type of signal? Being on an exactly even MHz, it could be a birdie.

 

[sumanta39]

Nothing but hissing sound by WFM

Hi guys,

Thanks for the prompt reply. Tried the same with WFM but nothing but hissing sound. It does seem like a dead carrier like signal as Dave has said but when I zoom it I can see some activity. However when I swipe across the AM frequency selector over the signal I can here some whistling sound. Also I found similar signal at 480 mhz (480 = 120 * 4 does it ring any bell?? ) and it is stronger. Here is the screen shot of the same in the attachment.

 

[slicerwizard]

Probably noise from your PC or some other equipment.

 

[sumanta39]

It was not from the antenna indeed!

When I unplugged the antenna it was still there only without the harmonics. So it was noise indeed..

 

[Arminius75]

120 Mhz

Are you near an airport? I had the same problem and found that I am picking up Dulles main tower 120.250Mhz.