I constructed this RF PROBE this afternoon. The idea is to be able to "sniff" for rf around circuit boards ,amplifier stages, oscillators etc, This probe has high spatial resolution which means that it will respond to close in signals. An amplifier might be amplifying on one frequency and oscillating on another higher frequency without the operators knowledge. With the probe connected to a scope it may be able to display the spurious signal as well as the fundamental. Sometimes a tunable rf amplifier will burst into oscillation at some particular setting of the tuning capacitor, due to a change of impedance etc. With the probe applied just above a tuned element in the amplifier stage, then by adjusting the capacitor through the tuning range and with reference to the scope the amplifier may be checked for stability. There must be lots of uses for this kind of probe. If higher sensitivity is required an amplifier may be placed between the probe and the scope. I hope others will build this probe as it is very useful
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