recently I built new Voltag regs for the 5v servos end the decoder. It was set by fault to 5,25 which caused some Track finding issues. but maybe i have som picky parts ...however - reducing to 5V resolved the issues.
If I use Super-Raygulators to regulate the servo amps will they provide enough current?
Q105 and Q106 I'm fairly confident about, but I know QM01 draws quite a bit of current, just not sure how much and can't find any data...
If I do need to change some components what are the recommended changes? BD139 has been suggested rather than BC547, but this has a lower hfe so the circuit becomes less efficient - is there a replacement with the same hfe that can handle higher currents? Of course I'll need both NPN and PNP for these amps.
TIA
Q105 and Q106 I'm fairly confident about, but I know QM01 draws quite a bit of current, just not sure how much and can't find any data...
If I do need to change some components what are the recommended changes? BD139 has been suggested rather than BC547, but this has a lower hfe so the circuit becomes less efficient - is there a replacement with the same hfe that can handle higher currents? Of course I'll need both NPN and PNP for these amps.
TIA
Hi,
I wouldn't use the super-regulator at all...
Just an LM317/337 combo will work fine for the servo's. Set it to 8 or 9V, but you need sufficient input voltage! 10,5V is the bare minimum, under load that is. 7808 & 7908 will work as well, even simpler.
If your input voltage is low-ish, you can use low-drop regulators, they need about 1V between input and output, or even less, depending on the type.
If you really want to try the super-regs, you should be aware that this requires an even larger voltage drop because of the extra input filter. If you're using an external transformer, this won't be a problem of course. You could use a darlington for the gyrator, so the base-current stays low.
Regards,
Ray
I wouldn't use the super-regulator at all...
Just an LM317/337 combo will work fine for the servo's. Set it to 8 or 9V, but you need sufficient input voltage! 10,5V is the bare minimum, under load that is. 7808 & 7908 will work as well, even simpler.
If your input voltage is low-ish, you can use low-drop regulators, they need about 1V between input and output, or even less, depending on the type.
If you really want to try the super-regs, you should be aware that this requires an even larger voltage drop because of the extra input filter. If you're using an external transformer, this won't be a problem of course. You could use a darlington for the gyrator, so the base-current stays low.
Regards,
Ray
Last edited:
Thanks, Ray. I'll go with one of the simpler options then, probably 317/337's with the power tapped from the +/- 12V rails - the opamps will have super regs on them and won't be connected to these rails any longer, so no danger of noise transfer.
I'm afraid that's not possible... The analog power rails can't supply the high current draw of the servo's. This secondary winding is much thinner.
There are two solutions: use an external transformer, or enlarge the caps for the servo voltage and use low-drop regulators.
There are two solutions: use an external transformer, or enlarge the caps for the servo voltage and use low-drop regulators.
Ah, thanks for the heads up on that winding, didn't realise it was thinner. What sort of VA rating would I need for a suitable tx?
I did some measurements on these players in the past, the servo/5V winding is loaded with max. 225mA during skip actions. Peaks can be a bit higher.
You need 10V AC minimum for the servo voltage, so at 225mA that's a power rating of 2.25VA. This goes times 2, because you need +/-10VDC, so that totals at 4.5VA continuous power consumption for the servo's.
Since you'll want to cover the peaks as well, I'd recommend a transformer that's twice or three times as large, say 15VA. But if you come across a slightly larger tranny, that won't hurt of course 🙂
Ray
You need 10V AC minimum for the servo voltage, so at 225mA that's a power rating of 2.25VA. This goes times 2, because you need +/-10VDC, so that totals at 4.5VA continuous power consumption for the servo's.
Since you'll want to cover the peaks as well, I'd recommend a transformer that's twice or three times as large, say 15VA. But if you come across a slightly larger tranny, that won't hurt of course 🙂
Ray
Excellent, thanks Ray. I'll have a trawl thru the Farnell website and find a suitable transformer.
P.S. Just installed your Flea kit on the DAC, player still warming up but it already sounds much better, soundstage has really opened up😀
I thought it was going to give me grief at first as it didn't spin the disk at all on the first startup; gave a radial error code (error 10). Out with the board again to find out what I'd done and discovered that when I'd soldered the earth wire onto the Flea board the other end had got hot enough to come off the earth plane next to the DAC! (it's a very short wire). One connection re-soldered and all is good.
P.S. Just installed your Flea kit on the DAC, player still warming up but it already sounds much better, soundstage has really opened up😀
I thought it was going to give me grief at first as it didn't spin the disk at all on the first startup; gave a radial error code (error 10). Out with the board again to find out what I'd done and discovered that when I'd soldered the earth wire onto the Flea board the other end had got hot enough to come off the earth plane next to the DAC! (it's a very short wire). One connection re-soldered and all is good.
Wow 2085 pages! I'm not lazy but that's like 10 years of posts to read :O
Hi 6h5c! Can I start with the pdf you posted in March 2005, or do you have a latest cd63mk2 modification PDF?
Hi 6h5c! Can I start with the pdf you posted in March 2005, or do you have a latest cd63mk2 modification PDF?
Just hooked my modified CD67 OSE to a Pioneer A-400 amp, holy **** it sounds good!
My system now finally sounds like I always dreamed it would.
Tom
My system now finally sounds like I always dreamed it would.
Tom
@ Steven Z - Yes you can use Ray's list on page 1 of this monster thread - it's what I'm basing most of my mods on and is still valid, though some part numbers may have changed. Check out his site on Ray's Audio Page for service manuals and a few more tips on some of the mods eg voltage regulators etc. - it's an excellent resource!🙂
Yep, it's a loooooooooooooong thread! 😀
The old list is still valid, but the CD63mkII-KI list is the most recent for this type of player. The CD 53, 63, 63mkII and KI all have the same board inside, so the list can be used for all players from this series.
Regards,
Ray
fav
btw whats your fav. mod - or lets say which of your moded machine sounds the best (for you) ?
sorry if this question is redundant.
btw whats your fav. mod - or lets say which of your moded machine sounds the best (for you) ?
sorry if this question is redundant.
My favorites tweakings are improving the analog output stage / filter and fitting a good clock. Enter DOS and the Flea, but other products can give equally good results of course. I have both in my SA8400 and I think they are great upgrades.
That doesn't mean that other tweaks have no effect, like upgrading the power supply or regulating the servo's. But the DOS, for example, replaces the entire analog output stage in one go, and that's a large step (and that's not just because I happen to sell the boards... It's the other way around in fact, I initially etched some boards for myself. Then I got more and more requests for it, so I decided to order a small batch) 🙂
You need a good power supply and regulators for both, to get the most out of them.
That doesn't mean that other tweaks have no effect, like upgrading the power supply or regulating the servo's. But the DOS, for example, replaces the entire analog output stage in one go, and that's a large step (and that's not just because I happen to sell the boards... It's the other way around in fact, I initially etched some boards for myself. Then I got more and more requests for it, so I decided to order a small batch) 🙂
You need a good power supply and regulators for both, to get the most out of them.
Last edited: