Dear friends, just finished my remote HF station running on solar energy and a big disappointment on 21mhz.All band during day time is unusable due to LO RFI of my MPPT 100/30 charge controller.
Does any one find any filter solution about it?
Is there any other MPTT model with no EMI/RFI at least on hamradio bands?
I ll try tomorrow with some ferrites on power input & output to see if there is any difference.
Thank you.
Hello sv9djo,
I experience the same problem on the HF radio on our yacht. RF noise seems to be a design parameter that many manufacturers are not too concerned about. When I am really trying to use the radio I mostly turn off the MPPT via the bluetooth. A bonus is it does not interfere at night! :-)
Regards,
Trevor
Update, I tried some Ferrite clamp - KGS TFCK 16-8-16 on both input & output voltage about 3 per cable, and seems to work ! I ll try FT-240-31 to check the if the result is the same.
Yes, the MPPT is an "all-band transmitter" when active. The RFI is coming from the MOSFETs. The design didn't incorporate slew-rate control. Ferrite RFI chokes help, but not completely.
I've done much the same as Trevor, but I installed a relay that's powered up with my antenna turner to disconnect the PV output, thereby shutting the MPPT down. You can do the same with a switch. Kinda sad we have that problem...
73 N8QH
I use 2 100/20 on my garden plot and I have no problems. A panel is located under the FB53 antenna. all cables are laid 35m parallel in empty conduit up to the garden shed. We also use an FD9 antenna there for 160m.
Nice setup Marcus!
With sailboat installations, part of the problem is the very small area in which everything is crammed together. The RFI I see appears to be common mode noise, and may very well be inductively coupled to my receiver. A few meters of separation between the MPPT and the radio or antenna would probably mitigate the issue but, on a boat, that spacing isn't available.
RFI suppression seems to be a Black Art where successful trial-and-error efforts work in only one specific installation. The only advice I could offer is: keep trying until you find something that works. Bonding, shielding, inductive or capacitive suppression ... just keep trying each until something works. Then sample every frequency, since you may have just moved the problem to another band.
