As you make the RF probe better able to handle high RF voltages you will also cause it to be less accurate at lower RF voltages.
The common RF probe diodes have a turn-on voltage of about 0.2 volts. Below that, they are almost open circuits and have no output. Higher PRV diodes have turn-on voltages of closer to 0.6 volts - three times that of the more sensitive diodes. So it takes three times the RF voltage to even begin to show a DC output and you'll need to be well above the turn on voltage to show an output that accurately indicates the RF applied. Put two or three diodes in series and you'll need 1.2 to nearly 2 volts to just start showing some indication of an output. Bottom line, don't try to use such a probe for low RF levels. Ron AC7AC _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
