Intripped wrote:thanks JOK3RX!
i've checked the schematic against your drawing of the circuit-layout, and i've found two errors:
- at the input, 68k and 1M resistors are swapped (should be 68k in series with the signal and 1M to ground);
- at Q4 - the 1uF capacitor that is connected to the source goes directly to ground, there's no 1K resistor in series with it.
I'm checking against the pics now
ok, i've checked the pics also, and spotted two other errors:
- there's a ceramic cap, connected to ground, after the 68k resistor (that is in series with the signal) at the input - can't read the value;
- at Q3 - the 1uF capacitor is in parallel with the 1.8k resistor, and not connected to 220k/22n/470k as in the schematic and drawing.
Ok, the 68k and 1M resistors are corrected (I blame that on copy/paste and bad eyesight)
On Q4, I believe there is a 1k8 in series with the 1u cap.. See pic attached.
You got me on the ceramic cap on the input.. I can't fully see it in any of the pics I have, I can only see that it starts with a 1.. I would say that it's pretty safe to guess that it's either 100p or less likely 10p.
Still looking at the last one you posted.
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