Section
Power Supply
Amplifier
Tuner
AUX
Tape Deck
Audio CD
Description
Unit #1
- Tape Deck CPU reseted by the use of the hardware test circuit in the Motorola data sheet.
- Security circuit (not so important) of the tape deck removed by removing 3528
- Power supply capacitors replaced
- 7516 replaced
Not perfect since FM radio fails and left channel is a little bit silent during recording of a tape. Also it seems head to read the right channel of the cassette is almost dead.
Unit #2
Power supply
- Fuse 1476 broken
- 7477 broken
- 7478 broken
- undocumented fuse resistor 2.2E broken, right before C40 pin 8 (prepares the +12V for the uProc Board)
AM/FM Board
- 3404 broken
- 7310 toasted
- 7311 and 7314 replaced
- 6311 toasted
- Gear broken
- CPU toasted
- Lever out of shape
- Servo Slide sensor not working in fast forward mode
- LED not working probably
- Rec Mode killed internal fuse, also 6771 broken
- SAA7000 & SAA7020 replaced
- CDM2 replaced with one from Philips CD150
- Capacitors out of range and replaced
- Sometimes does not play tracks directly above track 10
Modifications
- OpAmps for CD Player and pre-amplifier
- New tape deck CPU with more features
- Bluetooth module for AUX channel
- New heatsink plate at the back
Unit #3
Tape deck
Tape mechanism required a reset of the CPU, a new gear, proper cleaning of oxidised head and a refresh of the pinch rollers. In addition the grease of the soft eject mechanism had to be replaced.
CD Player
CDM2 was back working by just replacing the capacitors.
Modifications
Added a full range of modification:
- OpAmps for CD Player and pre-amplifier
- Controller Board Revision C
- Remote Control
- New digital tape counter with position memory and clock
- Bluetooth module for AUX channel
- New heatsink plate at the back, fan at fixed speed
Unit #4
Tape Deck
The fly wheel is broken, lost almost all teeth and cannot be repaired. Waiting to get my hands on a donor with SER1 mechanism. Built a temporary solution with a printed fly wheel – we do to want to talk about wow and flutter.
I am using the tape mechanism from Unit #5 since it is working perfectly even with the original gear (let’s see if it lasts for a while)
CD-Player
CDM2 back working by replacing the caps
Power Supply
Transistor 7477 broken – however, all values of the service manual point out different values as on this machine.
Amplifier
The TDA2030 of the left channel was broken. I replaced both to avoid any disharmony.
Modifications
- OpAmps for CD Player and pre-amplifier
- Controller Board Revision D
- Remote Control
- New digital tape counter with position memory and clock
- New heatsink plate at the back with active cooling and USB connectors for uploading new firmware
- New improved gear and help for tape mechanism
- A lot of cables replaced
Unit #5
Tape Deck
Lid does not open, LCD shows all segments
CD-Player
Spins backward, does not read TOC. I used another controller panel from a device which has some issues with the swing arm. Now it’s back working.
Power Supply
Seems to be fine
Amplifier
Left channel not working
Unit used for spare parts since several plastic brackets and buttons are broken.