Stella ST459 motorboating
I can't recall the Philips eqivalent of this - it's a 4-speed, 4-track machine. Unusually for 1964 it's transistorised with OC series transistors.
There's a quiet motorboating (no hum) in the background, varying with the volume in stop. In play it's very much louder, but the playback sound behind the noise is fine. Oddly, in record mode the motorboating is almost silent.
The HT is stable at around -16v and doesn't vary. I've done the usual cleaning of switches but no good. The caopacitors are silver Philips which I haven't had much trouble with in the past, so not my first port of call.
Any ideas?
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