BandidoII improvements!

[Marcello]

Hi Carl, I have realized the BandidoII
The voltage on c5 is -3.7V. to the exit of the emitter of the transistor it is -2.3V... is it regular?
Frequency tx=10KHz amplitude 9V with light distorsion.
Rx confused of 180° respect tx and amplitude on the pin 1 of u7A of 80mV.
for now I feel a 50 cent to 20cm in air.
Can you give me some help on as to improve?
I forgot: Is C29 470 pF or 10nF?
If I give to the circuit with 8V as the eldorado do they increase the performances?
grazie!

[Goodrat]

Re: BandidoII improvements!

You should have -3.0 on T7 emitter.
Xmit signal I get 8vp-p.
One change I had to make was to add a 150K resistor to Ic5b pin 6 to ground. The signal at R69 was too high on the negative cycle when the Disc control was full CCW (4vp-p) and would cause the output of IC5b to double pulse or oscillate decreasing my depth. The 150K prevents this by cutting down to 3v.

[Carl]

Re: BandidoII improvements!

Voltage on C5 sounds right, I think you should see about -2.7v on the emitter. Other stuff sounds right.

C29... I measured 0.43nF, so I assumed 0.47nF. I can't guarantee that I did not make a mistake, though! I doubt running at 8v will help.

- Carl