I got a non working Technics SU-Z2 that I have been unsuccessfully trying to get back to work. I am not an expert and I have been self learning about electronics on books and forums, and trying to apply that knowledge hands on with a few amps I got from friends or at carboot sales. This one had a lot of problems, from a very loose connection to ground, to filter caps in the power supply that measured 2pF, to one of the germanium diodes in the VU meter circuit that was shorted, together with some bad soldering joints in the cables sending the AC to the meters. I replaced all the caps, checked all the diodes and transistors and got new ICs just in case. Diode checking the STK2038 from pins 1 and 2, 4 and 5, 12 and 13 and 15 and 16 (collector base according to a schematic I found here on the forum for the STK2038) all measured OK about 0.6 volts. So I decided to turn the amplifier on, and after about 5 seconds the meters go full scale, and then slowly go back down to 0. The STK2038 becomes hot quite quickly. I checked all the voltages and what I found is the following: Pin 1, 3, 5, 6, 11, 12, 14, and 16 of the STK2038 jump to about +22V or more when I turn the amplifier on, and then slowly drop to about -4/-6V. All other pins measure OK. Q401 and Q402 measure OK, whereas the base of Q403 and the collector of Q404 jump around 1.5V and never stabilize. The collectors of Q301 and Q302 behave as the pins of the STK2038 that do not measure right in their voltages (jumping to about +22V when power is applied and then slowly dropping to -4/-6V) Both AN7060 have the same behaviour for pins 1 and 2 and 4, pin 5 measures -20V instead of -6V, and 6 to 9 measure OK. I also have the right +-15V for pins 4 and 8 of the 4559DD, but all other pins also jump to 22V and then drop. I thought that maybe the problem was in the AN7060, so I replaced those, but no difference. I am basically stuck, and even replacing all the other ICs has made no difference. There is something I am obviously missing here, but I can't seem to be able to figure out what it is. Does anyone have any guesses?