An Transmitted RF-powered LED WARNING light?
I am a disabled Veteran with too much time to fill. So, I volunteer at the Sheriff's Office doing light clerical work and a little target shooting, but my first love is HAM radio. It is a GREAT hobby! It is not without its hazards, though. My main transmitting antenna is a ground-mounted vertical in the back yard. We have six children with four still at home and while my kids know to NEVER touch my antennas due to the danger of electrical shock and nasty RF burns, their friends in the neighborhood may not fully comprehend the hazard.
The Challenge (if you choose to accept it):
So, what I'd like to do is to have a circuit out on the post supporting the antenna that would light LEDs, (preferably, four), whenever I key the mike - AND - have the entire circuit use the power from my own transmission... no power supply or batteries! It would also simply be a cool thing to have!
This is a vertical for the HF bands, from 7MHz to 30MHz and I typically transmit at 100 watts. The circuit would be at a distance of no more than six inches from the active element. I have seen crystal radio circuits in the past that used received RF to power a LED but don't remember where.