DigiTech GSP-21 Repair (Battery replacement + Power supply fix)

I bought an old rack mount effects unit from Digitech called the GSP-21. Initially, I thought it only needed a battery and while creating a video showing replacement of the battery I discovered there was a power supply problem causing a faulty memory. I got everything working now. Fun little unit.

1:41 - Battery Diagnosis
2:27 - Battery Replacement
3:14 - Testing New Battery
4:21 - EPROM / Firmware
4:59 - Photo of EPROM chip version 1.1u
5:15 - PCB tour / inspection
5:33 - Analog Equalizer Circuits
5:57 - OP Amp Datasheet
9:02 - Discovery of the Power Supply Problem
9:41 - Unit dead - troubleshooting
12:50 - Troubleshooting / measuring voltage across capacitor
13:36 - Found a bad connection in power supply
15:50 - Found cracked trace beneath PCB
17:01 - Power supply fix
18:38 - Testing unit
21:07 - Me Playing Music