Re: Uher CR240 Troubleshooting Best Practice
John - I did check, as that was the problem I discovered with the 6.2V supply. It measured all OK, with continuity between the two ends of the wires that connect the PSU to the motherboard, but the 6.2V on the PSU end was a fluctuating 2.8V on the other! I was glad to catch that one.
However, these traces are being made with the signal coming almost directly into the motherboard, with the plug assembly that links the tape heads to the motherboard out of circuit and the problem's still happening.
Lawrence - I *think* so. Perhaps you can tell me otherwise. Here's board 300 with the relevant transistors and the accompanying pinout. As it's showing the legs I thought it must be from underneath. The photograph is labelled with the transistors. The flat sides are all on the left. The top of the board is seen when in place, so the upper legs of the transistors are easiest to get at with the probe.
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