Sony PS-X70 Wow and Flutter

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Could perhaps someone point me in the right direction? My Sony PS-X70 has fluctuating speed and the platter turns a bit back when you press the stop button. So far I have checked the voltages of the power supply, replaced IC CX193 and crystal. All the other functions such as auto start/stop, return, up/down, 33/45rpm, repeat are working.
 
Hi Jon, After a long search I found that C2 and C3 were out of spec (ESR too high). C15 measures an ESR of 50, which seems way too high. It's a tantalum cap and I don't know what the usual ESR is supposed to be (0.22uf 35V). Should I replace all the tantalums for new ones from e.g. Kemet?
 
50 ohms seems high even for a conventional Al electrolytic of that spec. You can probably find a suitable film cap to replace it, 220 nF @ 35 V isn't that much.

It is very unusual for tantalums to go high - they can go short when overstressed, but other than that they tend to be very stable.

BTW, what measurement frequency does your ESR meter use? Impedance of a 220 nF still is 72 ohms at 10 kHz, you'd probably need to measure at around 100 kHz for a halfway dependable result on caps this small. So the high reading of C15 may be a pure measurement artifact.
 
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