Spurious signals in VHF 135-150 mhz band?
Posted: Sun Dec 24, 2017 2:58 am
I am trying to isolate a spurious signal that runs a portion of the VHF band. I see a series of spikes 25khz wide every 61mhz from about 135 mhz to 150 mhz. See screen shot.
I know these are from an external source as they disappear when I disconnect the antenna. (an external discone antenna)
Also, I know they are not SDR related, as I hear them in my 2 meter radio and its rubber duckie.
My best guess is a noisy power switching supply? (but there are lots of 'em around here. I'd probably have to kill circuit breakers to stop them)
Any ideas?
Russell
I know these are from an external source as they disappear when I disconnect the antenna. (an external discone antenna)
Also, I know they are not SDR related, as I hear them in my 2 meter radio and its rubber duckie.
My best guess is a noisy power switching supply? (but there are lots of 'em around here. I'd probably have to kill circuit breakers to stop them)
Any ideas?
Russell
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