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134 Khz spaced signals

Aug 26th 2020, 15:50

W1KYB

Joined: May 3rd 2020, 21:37
Total Topics: 0
Total Posts: 0
I am seeing a 5 KHz wide 'white' audio signal every 134 KHz between 5 MHz and 20 MHz. Any clues?
Aug 27th 2020, 09:26

W1VT

Super Moderator

Joined: Apr 4th 1998, 00:00
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That is a rather high frequency which would suggest perhaps a high resolution monitor screen rather than a switching power supply. It may also be a high speed digital device.

Typically it makes more sense to locate a device first, rather than to spend a lot of time trying to ID it.

I'd suggest listening on a battery powered radio and shutting down all the power in your own home. There may be issues with battery backup and slow shutdowns of devices.

Zak Lau W1VT
ARRL Senior Lab Engineer
Aug 27th 2020, 13:14

W1KYB

Joined: May 3rd 2020, 21:37
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Total Posts: 0
Why would any device repeat every 134 KHz across a wide spectrum?
Aug 28th 2020, 15:19

W1VT

Super Moderator

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
Here are some attempts to answer the question of why signals have harmonics.

https://electronics.stackexchange.com/questions/32310/what-exactly-are-harmonics-and-how-do-they-appear#:~:text=The20of20square,so20signals20distorted.

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