[R-390] Tracking down low sensitivity 0 to 8 mhz problem

[Jacques Fortin]

Hi Jordan,
Well, that confirm my initial suspicion.
An Y5F ceramic class capacitor is a "Class II" capacitor designed for
coupling and decoupling purposes, but not for use in a resonant circuit.
This is described in length here :
https://en.wikipedia.org/wiki/Ceramic_capacitor
And in the attached AVX datasheet.

And yes, you can post your .pdf(s) here.

I have also run some tests with my HP 4192A Impedance Analyser.
The best 100pF ceramic cap I have in my bins scores a Q of 220 at 1MHz.
A 100pF EL-MENCO from a R-390A RF deck scores a Q of ~1800 at 1MHz
A 100pF EM dipped silver mica pushes the instrument to it's maximum reading:
Q of 2000 at 1MHz !

73, Jacques, VE2JFE in Montreal
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