powering a diy antenna matching unit illumination with rf

[p.larner]

i have a homebrew t match atu with a big roller inductor and 300+300pf differential cap,ive just made a stockton bridge and fitted twin needle meters,i have a white led in the meter,can i power that using a torroid over the internal coax rectified to the led ,just would be nice to have meter light when transmiting without more wires to a psu,is that a workable idea?.

[Terry Bites]

A high value resistor and neon on the line?

[CaptDon]

Sounds like a pretty horrible idea. LED's will blink when on SSB and their brightness will vary with SWR and CW power level. The best you might hope for is to rectify some of the RF and filter it with with a couple of hundred microfarads of capacitance then run that positive voltage to something like a 78L05 and drive your LEDS through a resistor or constant current diode. What power level are you typically transmitting at? It may take some digging to find a suitable rectifier diode that works well up to 10 meters and at your P.R.V. based on maximum expected power level at the 50 ohm input side of your A.T.U.

[p.larner]

its only for tuning at 10watts max in am or cw,as soon as the adjustment is ok i dont realy need to look at the meters,i am trying to cut down on the untidy wires hanging from my psu,thought using constant rf when tning a way of doing it?.