12-25-2013, 06:08 PM
Well, as far as I remember a discussion here, those caps in backelite blocks are not micas and are usual papers.
You can easily verify that by measuring the capacitance of that 700pF cap; if you see it gone significantly it is not then a mica as micas stay put. I have just measured three micas in my 90.....if it says 110pF - it is in fact 110pF, and 330pF is 332pF or so.
Now as to the precision, this particular cap though it is in the oscillator is not frequency-defining cap, it is simply a DC feedback bypass cap and so it does not have to be any special type.
You can easily verify that by measuring the capacitance of that 700pF cap; if you see it gone significantly it is not then a mica as micas stay put. I have just measured three micas in my 90.....if it says 110pF - it is in fact 110pF, and 330pF is 332pF or so.
Now as to the precision, this particular cap though it is in the oscillator is not frequency-defining cap, it is simply a DC feedback bypass cap and so it does not have to be any special type.
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