Re: Replacing "micamold" caps in oscillator section
Well I put them on a capacitance bridge (low voltage AC at 1kc/s) set to read ideal capacitance with parallel resistance
520pF read 535.9pF || 120M
1500pF read 1571pF || 10M
2700pF read 2943pF || 8M
2700pF read 2700pF || 12M
3000pF read 2990pF || 7M
3000pF read 3033pF || 84M
3900pF read 4117pF || 1.5M
The capacitance values are remarkably accurate, but the 3900pF is starting to look a bit suspect but the 520pF may well be mica.
Probably worth checking leakage at HT, clearly need a better bench PSU, but somewhere I do have an HT supply and yes I'm tempted to open the 3900pF one to see what I find.
A randomly chosen one of the "special" decoupling caps we all know is quite different
4700pF read 19nF || 20K (umm we know all about these....)
|