RFI Via Cat Cable

Mike G4HCC

I am picking up spikes every 478 KHz. on 10m. The spikes are from my solar system.
I have used a battery portable on the aerials no spikes on that. I have disconnected everything else in the shack including the Ethernet switch and used smart link. to another computer. I have run the 6400 on battery still the spikes are -99dB The cable from the router is CAT 6

Mike G4HCC

Thanks

John KB4DU

The problem is much worse if individual inverters are used at each panel. Preferred method is to use one main inverter, then noise mitigation only need be applied to the one device.

Mike-VA3MW

Please review this story for some ideas. You have to stop the spikes at the solar cells.

https://www.fair-rite.com/wp-content/uploads/2020/10/Brock-Fisher-April-2016-QST.pdf

Erik Carling EI4KF

If you are certain the noise is being picked up on the Cat cable, you might want to try screened (shielded) Cat 7. This one https://www.amazon.co.uk/gp/product/B08R73J4YG/ref=ppx_yo_dt_b_asin_title_o06_s01?ie=UTF8&psc=1 solved my problem. Given the inexpensive nature of these products, they could be worth a try without losing too much if unfortunately they don't help in your case.

Mike G4HCC

I have changed the main run from the router from Cat 5 to Cat 6 because of a problem I had on 2metre FM so replacing the cables from the switch would reduce the RF noise if nothing else. I think I have tracked the spikes down to the DC cable to the Solar array. The Yagi is very close to the panels. The cable can have 470 Volts DC on it so I need to get an Electrician to move the cable out from the wall so that I can put some ferrite rings on. Thanks Erik

Ed Woodrick

Have you tried running your Flex on a battery? Does that hear it?

Have you tried it with no Ethernet connected? or at least with only short cable between your radio and computer or Maestro?

Is your computer a laptop? Make sure to try it not plugged in,

Basic steps are to isolate everything and then find the source or sources that the problem comes from. Then you can figure out how to fix it.

With solar, does it change between daytime and nighttime? Do you have batteries and an inverter?

Mike G4HCC

Yes there are very small marks on the waterfall at night. In fairness to the Inverter I have a very small garden and the antenna is close to the solar array and DC line.

I use a Mac Mini but being a flex I was able to run the rig without the Mac. that showed no difference.
Also tried to the Mac without the ethernet connected to the switch.
A filter on the 240V supply to the shack and that dropped the problem by 5dB.