Barry@ I have cleaned and checked all the ribbon contacts as well as the IC tracks they are all OK. The problem still exists.
Ray@ I have not checked the voltages of QM01 but I believed they should be OK as the CDP functions normally. It can search all the tracks and play CDs like a normal CDP. The only problem is when I press the stop button the CD motor does not stop but rotates slowly in an anti-clockwise direction without stopping. May be I will change the laser unit to another new one and see if the laser unit is defective.
Ray@ I have not checked the voltages of QM01 but I believed they should be OK as the CDP functions normally. It can search all the tracks and play CDs like a normal CDP. The only problem is when I press the stop button the CD motor does not stop but rotates slowly in an anti-clockwise direction without stopping. May be I will change the laser unit to another new one and see if the laser unit is defective.
I am pleased that I have now solved the disc rotation problem. I will explain what had caused this problem.
With Ray’s advice I measured the supply voltages of QM01. The + and – voltages are alright and with no problem. I then measured the voltages of PIN 5,6,7 and 8 of QM01. All of them have 2.5V which are normal. After that I measured PIN 1 and 3 and they should be zero when at STOP mode but actually there were -0.15V on them. I then traced the source of this voltage and measured the voltage at R157. I found that the voltage was +5.5V instead of +5V. This +5 volt should come from Q811 (7805 regulator) which I had replaced with an adjustable low noise voltage regulator. I believed the voltage of this regulator had shifted when I carried out the repair work. After adjusting the voltage back to +5V the disc rotation had stopped and everything is back to normal. I have tried if the voltage to R157 is less than +5V the disc will rotate in the clockwise direction instead.
Problem solved and thanks for all the advice !!
With Ray’s advice I measured the supply voltages of QM01. The + and – voltages are alright and with no problem. I then measured the voltages of PIN 5,6,7 and 8 of QM01. All of them have 2.5V which are normal. After that I measured PIN 1 and 3 and they should be zero when at STOP mode but actually there were -0.15V on them. I then traced the source of this voltage and measured the voltage at R157. I found that the voltage was +5.5V instead of +5V. This +5 volt should come from Q811 (7805 regulator) which I had replaced with an adjustable low noise voltage regulator. I believed the voltage of this regulator had shifted when I carried out the repair work. After adjusting the voltage back to +5V the disc rotation had stopped and everything is back to normal. I have tried if the voltage to R157 is less than +5V the disc will rotate in the clockwise direction instead.
Problem solved and thanks for all the advice !!
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I forgot to mention that when I carried out the repair I also took the opportunity to change all the 100-120pF caps around the two opamps (Q605 and Q606) to polystyrene Axial capacitors. The sound is now more smooth than using the stock caps.
my marantz 67
hi the player looks really nice how does it stack up against £5000 cd player i ran a 67 off battery except the op
amps i was so happy with it it was as good as a linn player what clock do you use
Yep, only 1 clock in a 67 Al.
Also, there are 2 5v regs as the servo section is regulated as std. Std 67's sound better than 63's due to servo.
Same cap mods apply along with everything from the DAC backwards 😉
63's can be pushed further than 67's due to the more discrete decoder and servo.
Here's one i did earlier!!!!!
hi the player looks really nice how does it stack up against £5000 cd player i ran a 67 off battery except the op
amps i was so happy with it it was as good as a linn player what clock do you use
Not yet. I'm trying to decide what to do. I still have 7812/7912s and cheapo metal film resistors in my DOS that need upgrading.
Oh hey, higlander, I just read your previous post. My disc also spins slowly while in stop mode and I'd often wondered why. My LM317-based regs put out just over 5v, so that sounds a likely cause. Thanks!
No need to say thanks. We all learn from each other 😉🙂
I started my modding projects a year ago after going thro' more than 1000 pages of discussions here and dropped down all the important points before I decided what to do. The results are amazing and so far I have done modifications on 8 CD63s for myself and my friends 😀 I really enjoy all the soldering work and of course the music from all the CD63s 😀
It's amazing, almost 20.000 messages and this thread is still alive!
Next year we'll have a ten-year anniversary 🙂
Next year we'll have a ten-year anniversary 🙂
