From: "Chris Wheeler" <cwheeler2@TELSTRA.COM>
> HA! Thought so. The article has the C8050 pinout the wrong way around.
> http://www.ushasemi.com/pdf/Transistors/C8050.pdf
>
> Pins correct for the BC549 tho.
> http://www.electronicsplanet.ch/Praxis/datenbla/BC549.pdf
>
> The other circuit has inconsistancies too. There is a 220 ohm resistor
> between the capacitor on Q3's emitter and gnd. I don't see it on the
> schematic, but its there on the the PCB.
>
> I'm building the circuits on a breadboard with fresh parts to work out
where
> the problem is. So far I've verified the 555s work and the first stage is
> oscillating.

I tested the LM386 on breadboard and made a crude amp from the data sheet.
I've been able to verify The Fox works now on the pcb.

The probe PCB still wont amplify, so I'm planning to build the circuit up on
the breadboard, and if it works as advertised, then the PCB must be open
somewhere.

I built the other probe that Rick C posted and that works. I've had to
compromise with the component values, 220ohm and 270ohm rather than the 240
and 260 in his circuit.
It works very well.

--
CW

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