Posted on 07/20/2012 11:52:17 AM PDT by onemiddleamerican
Image of interference/jamming on WWV at 5MHZ:
And Image of same on WWV at 10MHz:
NIST website says their readability is excellent, but bar graph is not showing there.
My friend is getting the interference on his fancy radio rig. He asked me to ask Freepers for ideas, thoughts, similar experience. He doesn't have a Freep account but will read comments.
Solar Flares and Sun Spots cause interference on HF Radio!
HAM SWL DX Ping
;-)
/johnny
At 10mhz, wouldn’t that be cordless phones, 2 way radios, baby monitors and things along that nature?
WWV is pretty clear at 15 mHz.
Looks like local noise to me - very possibly from a computer or some device with a switching power supply.
No sign of anything like this at 5 and 10 MHz here in Northern Virginia. Can’t hear WWV at 5 MHz during daylight but there’s also no trace of noise or interference. 10 MHz shows only WWV. Weak due to poor propagation, but no broadband hash observed.
Jack
Damn squirrels...
Just for a laugh, maybe it is this?
http://www.photofacialmachines.com/shop.aspx?p=11603&k=10Mhz-Radio-Frequency-Facial-Lift-Body-Slim-Spa-Machine
And thanks to all for your replies. I will leave all the techie comments to you guys now. My work here is done. A new Freeper will be entering through the podbay doors soon...
“At 10mhz, wouldn’t that be cordless phones, 2 way radios, baby monitors and things along that nature?”
No.
10.000 - 10.000 Time Standard WWV
10.005 - 10.100 Aeronautical Mobile Transoceanic Flights
10.100 - 10.150 Amateur 30 Meters CW Only
10.100 - 11.175 Fixed Service
thx
No Problemo.
I haven’t a clue what it is, but it does appear to be local.
My first thought was a clock signal from something that is leaking.
Though I am used to seeing 10 Mhz clocks
is his beeber set to stune?
A leak in the local cable company plant will cause noise in the 5-42Mhz range (upstream carrier).
Otherwise I would look at power-line amplifiers, or any fluorescent lighting/signage indoor or outdoor.
It’s really hard to say from just looking at a spectrum plot. Listening to the interfering signal on a receiver would provide clues. If it sounds like a constant 60 Hz buzz, it could be a switching power supply, CFL bulb, etc. If there is a computery-sound to it, it could be a nearby PLC data link that uses HF frequencies on power lines for data transmission. If it a voice signal, it could be a harmonic from a nearby AM station that has a problem in the output filter. If the problem continues, have him look up a nearby ham radio club (search at ARRL.org) and they can help locate the noise source.
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