redpackman
Active Member
I've got a Philips GA-212. My problem basically is that it only plays (judging by the strobe on the platter when looking at it with my fluorescent light) at 45 rpm. I can follow the service manual (which I have thanks to VinylEngine) and set the 33 and 45 controls to center and then adjust R471 to get the 45 rpm right on. But the 33 start button does start the turntable but it goes to 45 rpm and adjusting R449 or the 33 rpm trim does nothing. A couple of times when I first had it, it would play at 33 rpm AND the green light under the 33 would light. Now it plays at 45 rpm and the light stays dark though I know it's still good. The light for the stop button and 33 button both are good, but only the stop light works. There is no light in the 45 rpm socket.
I've adjusted R472 so that the voltage to the circuit board is -9v.
In short all three 33, 45 and stop buttons "work" in that they cause the TT to start turning or stop as directed, but the 33 rpm button starts it and it goes only to 45 rpm. I DO also know too that you have to press the "stop" button between selecting either 33 or 45.
Another question but unrelated to the above. The manual says that with the TT in the "stop" position and "on" one should get .75 volts "across" R404. Is R404 the light sensing cell? Secondly where does one take that reading? AT the end points of the two gray wires that emanate from the light sensing cell where they attach to the circuit board?
I've adjusted R472 so that the voltage to the circuit board is -9v.
In short all three 33, 45 and stop buttons "work" in that they cause the TT to start turning or stop as directed, but the 33 rpm button starts it and it goes only to 45 rpm. I DO also know too that you have to press the "stop" button between selecting either 33 or 45.
Another question but unrelated to the above. The manual says that with the TT in the "stop" position and "on" one should get .75 volts "across" R404. Is R404 the light sensing cell? Secondly where does one take that reading? AT the end points of the two gray wires that emanate from the light sensing cell where they attach to the circuit board?