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Mike. Watterson · 31st Mar 2019, 8:29 pm

I've a selection of saved highlighters, possible projects in addition to injector:
KV probe for 10M DMM using 33M HV resistors, a longer highlighter.
Peak detector 1nF series, 2 x 1N60, 100K load and 1nF. Feed wobulator in, scope or DVM.
L.O. or IF sniffer, basically very low capacitance FET buffer so as to not pull off frequency.
Voltage probe / battery tester with bargraph IC, high impedance or 470 Ohms.
Electrometer probe, either Rod pentode (robust) or FET to drive DMM, more than 100M input impedance.
RF probe, logic probe, logic pulser already mentioned.

Also useful and saved are the metal tip flat highlighter style white correction pens. I suspect the dremel cutting wheel will cut of the ballpoint tip if it's a problem.

31st Mar 2019, 8:29 pm	#5
Mike. Watterson Heptode Join Date: Dec 2014 Location: Limerick, Ireland. Posts: 901	Re: Signal Injector. Highlight Pen. I've a selection of saved highlighters, possible projects in addition to injector: KV probe for 10M DMM using 33M HV resistors, a longer highlighter. Peak detector 1nF series, 2 x 1N60, 100K load and 1nF. Feed wobulator in, scope or DVM. L.O. or IF sniffer, basically very low capacitance FET buffer so as to not pull off frequency. Voltage probe / battery tester with bargraph IC, high impedance or 470 Ohms. Electrometer probe, either Rod pentode (robust) or FET to drive DMM, more than 100M input impedance. RF probe, logic probe, logic pulser already mentioned. Also useful and saved are the metal tip flat highlighter style white correction pens. I suspect the dremel cutting wheel will cut of the ballpoint tip if it's a problem.