There was a little problem left on unit 2: pressing record caused an electrical short and a fuse on the AM/FM Panel got toasted. With he help of some picture from the other machine I figured out the undocumented cable was on a wrong pin. Hell, someone soldered it to the wrong position! Just took me some hours to recognise […]
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Two CDM2 repaired
Since the CDM2 from the donor Philips CD150 is not working properly – if has problem to jump to tracks, especially track 7or higher – I had to prepare another spare part. The CDM2 from the second donor CD150 was working fine and I just replaced all the capacitors. Inside the CD150 I got a CDM2/10 and a CDM2/29. Seems […]
Unit #2 almost finished
During the last days I reassembled unit #2. Of course it was not as easy a I thought. First problem was my CPU replacement board which builds too high to have enough space between the uProc and the cassette panel. However, I had a third PCB and completed it with elbow connectors and lower IC sockets. Furthermore I removed the […]
The hardest thing…
when repairing this old machine is the cat. I am always searching for parts which are spread around the house. Very nice when you step on an IC, gives a nice pattern on you foot. Lego is for beginners…
CD Player working
Since there were a lot of issues with the CD Player it took some time to solve them. First the Decoder Panel was not working. After putting all the ICs on a socket and after I exchanged all capacitors the replacement of SAA7000 and SAA7020 did the job. In the same time I have done some optimisations to the circuit. […]
CPU replacement issues solved
I have tested the new CPU replacement board outside with a 12V supply. When finally mounting it to the uProc board and used the 6.4V supply of the board I run into one issue. The clock signal for the CD-CPU should be 5.8MHz but was flat. One issue have been the two capacitors I was using for the 7805 to […]
CD spare parts and where to find them
To be able to locate the defect on the CD-Player I do need some spare parts. Right now the error could be somewhere at the CDM2 mechanics/controller board or at the decoder panel. I do not want to disassemble one of my other two devices for testing purposes, thus I have done some research in which CD-Player from Philips or […]
More CD-Player issues
After the amplifier is working it is time to check the CD-Player. Unfortunately it was not all the time working. Sometimes the CD was spinning faster and faster, the controller was unable to read the TOC returned an error. It was working better when the Decoder Panel was in a vertical position. So I thought it might be a loose contact. I […]
Repairing the amplifier – Part2
Well, the preamplifier is working and not to continue with the TDA2030. Since the channels are separated but both do not have a signal it was quite clear it can only be a control of both channels which is not working. Luckily there is only one circuit that can cause the troubles. The circuit around 7310-7314 mutes the signal for […]
Repairing the amplifier – Part 1
After I have repaired the power supply of the second unit and check all of the provided voltages it was time to continue with the amplifier. Since there is no sound on both channels it must have something to do with either the supply or controls. In a first step I checked the voltages and noticed F with +38V was […]