This is a new one for me.?
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I copied a couple of old sources for ft testers but some of them just vanished from the hard drive. One was a real nice PNP/NPN with a VFO and meters. 1960s. You could test common base or common emitter max oscillator use. Alpha Test or something.
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An old VHF manual had this in it. Was trying to squeeze it into an altoids tin but moving interrupted that build.? I wonder where it is....
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At the time, I was looking for a small variable cap 1 to 100pf. Just may go with a multipole mini rotary.....
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There is this one from techlib
Ft tester and included is an LTspice file. This could be automated with a micro, 5351, a couple of diodes,
and a display.? Maybe add the DC beta test, and the BVcbo, BVceo, BVebo and .... mission creep.
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?The test is done at about 10 mA. The CAL and OUT points would typically connect to a scope, preferably
through coax terminated with 50 ohms at the scope, but 50 ohm resistors and scope probes
should work, too. Other measurement devices will also work. The user plugs in the transistor
and adjusts the frequency of the signal generator (set near 10 dBm out or lower) until the
signals at CAL and OUT are equal in amplitude. F is 20 times that frequency
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ND6T made a simple? tester from an ?absorption wave meter from a hamfest. I have only text, the images didn't come through
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