Until the PLT takes over...
You have my sympathies Ken, I also suffer from a plethora of "transmitting devices" which seem to love hogging the more important frequencies at just the wrong time. Having gone to some considerable trouble to eradicate QRM from SMPSU's in my home and PC equipment (originally band was S7 broadband, now S0) it seems that EMC issues are set to take over.
I can vouch that for VHF, the homeplug style of PLT can be disruptive (for HF quite devastating in some frequencies) and like other areas of electronics it seems that the marketplace is being flooded with kit that is marked 'CE' but that certification is often dubious at best.
All we can do is club together and pool our knowledge and discoveries. The new page here http://www.70mhz.org/uss.htm
I feel will be an important contributor, I hope it stimulates an interest in a movement to stamp out some of this annoying QRM.
Like you say, sometimes it all gets too much and although we have a string affinity for this band, one can't help but throw one's hands up in the air sometimes and say "what's the point?"
But why should we have to switch off????
GL Ken, I hope you get your trouble sorted.