As far as economical project power supplies go, you simply can't beat plugpacks anyway with extra filtering and regulation on board as needed. Author will remain anonymous. Frank, You say you are an amateur radio operator but you did not give me your call sign . The short answer is forget it, i.e. payback. I can recollect some 20 odd years ago experiencing a similar problem although that was largely rectification in mine and my neighbours' Hi-Fi's.
Matters only escalate.
The long answer is for you to contact a local amateur radio club or the A.R.R.L for guidance. Submit your problem to them because if the problem is as bad as you describe then certainly others are similarly affected. C.B.er's after a lot of trouble and expense to yourself and worst of all, as you say you are an amateur operator, lower our high standards of behaviour down to theirs. Sorry but that is the advice I can and will be prepared to offer. Best regards in your endeavours and thanks for your note.