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Re: SP10 Troubles

Posted: Sun Dec 09, 2018 12:01 pm
by Nick
If needed, host them somewhere else and just supply a link. If you are going to post scope traces, get your scope to dump to a usb stick and send the images from that, no need to see the entire scope.

Re: SP10 Troubles

Posted: Tue Dec 11, 2018 1:10 pm
by Wolfgang Felber
Hi Nick, the SP10 Mk2 that I have has been modified by the ABC in OZ. I will attach some more photos.

Re: SP10 Troubles

Posted: Tue Jan 08, 2019 3:53 am
by Wolfgang Felber
Hello to all SP10MK2 owners, I finally got mine running but had problems locking onto speed, so in my haste I tested the oscillator using C1 and C2 on the drive board, bang, 32 volt fuse popped, replaced fuse and all I get is the clicking of the brake solenoid. Platter doesnt spin, I have put some of my measurements down below. Appreciate any help.

A3 & A4 the field generator coil measured 264.64 ohms
The motor windings each gave a reading of 14.1 ohms, that was from common to each of the windings
The voltage coming from AC to A1 was 0.625 volts or 625 millivolts
The voltage coming from AC to A2 was the same.
The voltage coming from AC to A3 was only 115 millivolts, is there something wrong there?
I also noticed that the heat sink was very hot, I could not pinpoint which transistor was causing that amount of heat.
I also test the MA150 diodes, d11 was giving a good reading of 0.625 millivolts from one side which was common on all the MA 150,s, the difference with D11 is that reversing the leads on the other three gave a reading of 1.125 volts where D11 was OL. Does this sound like a faulty diode. These I believe can be replaced with IN4148 diodes from Jaycar. I tested all the resistors and they were OK.
My next step will have to be testing all the transistors which is going to be a long job.

Open to suggestions.