QRM from switch mode power supply

This is the radio noise from a switch mode power supply affecting amateur radio band 1.800 - 2.000 MHz. The noise was removed almost entirely by inserting a 230V AC noise filter in series with the power supply cable.

Category:

Science & Technology

[umery2k75]

How did you get the idea, that noise would be present at 1.8-2.0Mhz?

This must be a hit and trial method.

You must have put a RF choke in the main line to prevent this interference from happening.

[rdehli]

Yes, I put a AC Line Noise filter on the Switch Mode Power Supply AC cable. That stopped 99% of the noise.

[umery2k75]

What is that instrument that you have?

[rdehli]

It is the amateur radio transceiver Icom IC-756pro3. It has a spectrum scope for monitoring up to +/- 100kHz from the receiver frequency.

[NZRadioGuy]

Hi there, thanks for video. 73  NZRadioGuy

[combatwombat71]

AM is always better for checking out your man-made 50HZ/60Hz noise floor. I have been chasing noise around my QTH for a long time now. It's pretty bad, as my videos show! 73.