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N_Cook N_Cook is offline
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Default Tektronix 221 , hand held oscilloscope from the 1970s

Same static set up with changed Qs. Same ones high and low. Taking the base
of the off one high will switch it on, then returns on release, doing that a
few thousand times would put some charge in the batteries. Changing the
silver mica? cap made no difference. There are a few probably multilayer
ceramic caps that are the next things to change for the same reason,
especially C622 near the base of that off Q. I wish I knew what all those
+5V taps are doing on the hot side of the charger unit, the +5V only comes
up with oscillation of the main power supply off the batteries