Working on a new Zeta-Sound design. I’m in the tryout of a new idea. Right now the circuit is undergoing some testing and tweaking of component values. Making it sound as I imagined it would. We’ll see what comes out of it. Stay tuned for more info.
Circuit board fitted in a Hammond 1590B enclousureCircuit board populated.
Got two Rats of different generations on the bench for repair. The v2 to the left, not working at all. The other one did not reach unity gain.
ProCo RatsProCo Rats guts
I had to replace a malfunctioning jfet source follower on the output stage on the old Rat.
Non working jfet transistor
The other one had already been messed with. There were several copper traces on the circuit board that had to be mended, the opamp was burnt and wires not connected. Managed to bring it back to life again.
Finally had some time to mount the hardware in my new tube pedal design, Lady Dirt. Strange how every build sounds so much better boxed up with some nice graphics.
High voltage tube pedal Lady DirtHigh voltage tube pedal Lady DirtHigh voltage tube pedal Lady Dirt
Led would not lit at and it did not pass any sound. Opened it up and took some voltage readings. It did not get any coltage due to a bad battery clip.
Morley Bad Horsie VAI-1 circuit board
After replacing the battery clip it powered up but the led L1 would not lit. Turns out the led was damaged. Had it replaced and adjusted so the circuit would go into bypass mode when the foot is of.
Morley Bad Horsie VAI-1 L1 replaced
I like the way that the bypass circuitry is built. Never seen a led/ldr combo used with a hex inverter to control the switching fets, works fine on a wah pedal.
Also fixed some new screws for the bottom lid, the old ones where missing.
Got this one in for repair, would not make a sound.
SubZero TUBE-H5
Sometimes it’s an easy fix, when opening the back I found the 12AX7 preamptube at the bottom of the chassie. Just put it back in place and it was ready o rock.
I opened it up and took a look at the circuit. Besides from the single 12AX7 preamptube and the EL84 power tube there’s two JRC4558 opamps on the circuit board, so what we got is a hybrid of solid state and tubes.