22-09-2019, 12:30 PM
(22-09-2019, 06:31 AM)Crackle Wrote: I tested the PSU and there was some noise on receive, but this mostly went when I reconnected the PSU earth link, which I had lifted. Transmission reports come back with clear mod and no background noise, may need to confirm this with more local reports.
Also no indication of breakthrough on FM which I was getting before with the commercial Ham type PSU I bought and sent back. The breakthrough on that was cured when I isolated the earth to the PSU, but I didn't wish to run the PSU with no earth and didn't want to invalidate warrantee by adapting the internal circuit to remove the mains earth from the DC output negative.
But I am happy to say the PSU seems suitable from RFI point of view, I think further improvement can be made on receive by earthing the PSU to the transceiver, better screening, and or adding more common mode filtering on the OP.
Its interesting to note that when the PSU is turned on there is a brief increase in noise on receive which goes after about 3 seconds.
Thanks
Mike
That's encouraging news. Shows it's worth persevering with this - I will do my best to borrow a PSU when I'm back at work tomorrow...
