To all who replied:
Thank you for sharing your knowledge on this matter. The cellphone charger sounds like the easiest way to go as a low voltage device to trigger the Powerflash module, easier still because I already have one that I can use. I would have spent lots of time and some money trying to configure this arrangement; it is unfortunate that a thermostatically triggered transceiver does not exist, as I believe that I am not the only person to want that device. When I think that instead of this, X-10 manufacturers make a warmer to "fool" the central HVAC thermostat, well, it makes me shake my head. The heaters that this arrangement will control are nice, fairly low consumption, fairly high output ceramic heaters whose only drawback is the lack of an incorporated thermostat.
I am grateful that this post elicited the gracious, informed response that it did. It appears to be one of the few Internet forums that does not engage in name calling because of a difference of opinion, or chide the ignorant for their lack of knowledge. The Internet as it should be.
Thanks again.
Noop