Re: Ampeg VH140C

Posted by TheChaplain on May 14, 2016; 9:20pm
URL: http://guitar-fx-layouts.238.s1.nabble.com/Ampeg-VH140C-tp30301p30627.html

Ok ok ok, first off:

VERIFIED  

The circuit does work but mine sounds a bit chunky and off.

For the diodes:
6.8vz = 1N5235BTR
3.3vz = 1N746ATR
12vz = 1N5242BTR

My initial problem was with the 1N746s. The band is actually anode so I put them in backwards.

Voltages:

Battery = 9.04V (8.89 when connected)

TC7660SCPA
1. 8.47V      8. 8.44V
2. 4.82V      7. 5.06V
3. 2.1mV     6. 3.61V
4. -3.24V     5. -7.66V

JRC4558D (right upper)
1. 3.2mV     8. 14.28V
2. 5.1mV     7. 4.7mV
3. 4.1mV     6. 6.0mV
4. -14.03V   5. 5.2mV

JRC4558D (left upper)
1. 2.9mV     8. 14.21
2. 2.9mV     7. 6.5mV
3. 1.6mV     6. 2.3mV
4. -13.98V   5. 1.7mV

JRC4558D (left lower)
1. -0.6mV    8. 14.13V
2. 1.3mV     7. 1.01V
3. 2.07V      6. 3.9mV
4. -13.95     5. 3.0mV

I've made all my off board connections on a breadboard (minus the pots) to avoid having to work with this inside a box for now.