Adding SMD caps like that (say 10 or 100nf) is something I have done in the past. Benefits... I hate to say it but its probably more of a "it has to better" kind of scenario.
With anything like this you need to know your enemy... and that really means scoping and seeing if a problem exists. The problem with any reg is that no matter how clean and perfect the supply is at the pins, go a few cm down the print and that super stable voltage is being modulated by all the goings on of the processors. Its at the destination where the supply should be as clean as possible.
With anything like this you need to know your enemy... and that really means scoping and seeing if a problem exists. The problem with any reg is that no matter how clean and perfect the supply is at the pins, go a few cm down the print and that super stable voltage is being modulated by all the goings on of the processors. Its at the destination where the supply should be as clean as possible.
So straight on the chip pins then
Thanks
And make sure you get the correct grounds as there can be several around large chips... analogue ground, digital ground etc.
vam 1202
Brent used a vam 1250 im sure in his last incarnation of his cd63,As for regs lower the noise @ the supply pin the better the sq.
alan
I fitted 3x lm317 based ray regs @ the dac and the sq raised by a noticible amount, Checked this out on a scope easy to see why.
It would need to much fettling, yes
One word of caution while we are on about pickups... the worm gear and main gear are not always interchangeable between pickups of ostensibly the same appearance. I'm thinking specifically of the CDM12.1 and 12.4 here that use the white and blue gear sets respectively. Fit a 12.1 gear set to 12.4 pickup and the sled will just keep whizzing from end to end as it tries to read the TOC. I suspect the backlash rather than ratios are different.
Brent used a vam 1250 im sure in his last incarnation of his cd63,As for regs lower the noise @ the supply pin the better the sq.
alan
I fitted 3x lm317 based ray regs @ the dac and the sq raised by a noticible amount, Checked this out on a scope easy to see why.
Last edited:
Brent used a vam 1250 im sure in his last incarnation of his cd63
alan
I had read somewhere in this forum that Brent utilized the casing of VAM 1250 but not the laser unit itself, may be I am wrong
re casing
Gears too if my memory serves me well ( smoother operation),may be im wrong.
alan
I had read somewhere in this forum that Brent utilized the casing of VAM 1250 but not the laser unit itself, may be I am wrong
Gears too if my memory serves me well ( smoother operation),
may be im wrong.alan
CPC were pretty efficient at getting me the part, turned up today after ordering yesterday with standard delivery. The box claimed it was "Made in Japan". Unfortunately one of the notches that holds the shock mounts in place was damaged and half of the notch fell off. Still, I thought I may as well try it as everything else looked good and it would probably stay put with three of the mounts.
Unfortunately there seemed to be something wrong with my hands when soldering, so it took me longer to do this bit. The solder wouldn't melt, wires wouldn't stay put. I melted some bits of plastic but nothing critical...
This unit worked immediately once I'd put it in. I didn't have to fiddle with anything and I put some grease on it before starting. Maybe that helped. Also swapped the cone as I know it works with the clamp magnet. Initially I'd pressed it on too far and the spindle motor got stuck. No radial errors. Hurrah.
Clearly I should have sent the original unit back, but I was impatient. At least I learned how the thing fits together despite the wasted time.
I'm hoping no skipping. I may have to try and fix the shock mount thing but the fact that the CD is clamped in to the unit probably means I can get away with it the way it is.
Unfortunately there seemed to be something wrong with my hands when soldering, so it took me longer to do this bit. The solder wouldn't melt, wires wouldn't stay put. I melted some bits of plastic but nothing critical...
This unit worked immediately once I'd put it in. I didn't have to fiddle with anything and I put some grease on it before starting. Maybe that helped. Also swapped the cone as I know it works with the clamp magnet. Initially I'd pressed it on too far and the spindle motor got stuck. No radial errors. Hurrah.
Clearly I should have sent the original unit back, but I was impatient. At least I learned how the thing fits together despite the wasted time.
I'm hoping no skipping. I may have to try and fix the shock mount thing but the fact that the CD is clamped in to the unit probably means I can get away with it the way it is.
OK I'm a numpty
I changed C508 instead of C505.
Put C508 back in and the new cap in C505 and YEEESSS, she lives.
I remember Brent saying the values around the Decoder were critical.
Oh well, no harm done, just a few wasted hours.
Slips like that are easily done. Great to hear its working
All part of the learning curve.
Sounds great.
Servo driver Regs and 3TX mod now.
Then two Spowers, when funds allow, for the decoder
Then its done.
re done
till the next mod trust me its an obsession
alan
Its never doneAll part of the learning curve.
Sounds great.
Servo driver Regs and 3TX mod now.
Then two Spowers, when funds allow, for the decoder
Then its done.
till the next mod trust me its an obsessionalan
+1. After I have done the 1st mod I can't stop doing another and add more modifications to improve the CDP further. So far I have done about 10 mods for my friendsIts never done
alan