Marantz CD63 & CD67 mods list

[SimontY]

Sorry if this mod's been posted before with pics, but I can't remember with the thread being so long!

To feed the servo chip cleaner power, cut R122 (digital feed) and R123 (analogue feed) and plumb in a 7805 for each (or share one, it will still give good gains).

Pin 3 of the 7805 is output so solder it to the resistor leg you left in place (you don't even need the board out for this work), pin 2 is ground - solder this to the PCB top (scratch the lacquer off with a fibreglass pencil) and bend the input pin (pin 1) back and feed it with a wire tapped from C813 ("+10V"). U236 or U237 is good for soldering your power wire to, but may need a clean-up with the fibre pen to make the solder flow easily.

[SimontY]

Here's Q106, which the service manual tells me does "radial" and "focus". That sounds important to me

This player didn't like -8V here (reg inserted in-line with U149) so I restored it, as you can see in the picture. I left the 7808 in place - perhaps it's useful to see how it's done. The negative regulator has a different pin-out so don't just wire that up the same - make a drawing of it and refer to it as you solder it up, and check it after you solder it. Otherwise it'll probably go bang on power-up

It's 100% happy with just 3 of the 6 voltage rails on the drivers regulated. I will do wire jumpers from the other 7808/7908 and regulate QM01 too.

[SimontY]

Here's where you can easily feed Q105 (sled/laser diode driver). My pics don't show it clearly but it's the same as with Q106, except you're cutting out resistors rather than a wire link.

ps - that blue wire feeds the analogue regs on the servo, decoder and DAC. The others currently run off the big 10V rail.

[SimontY]

These pics show the easiest way to add another transformer and power supply (or supplies) to the player. If you position it just right a fairly large toroid can be bolted to the back without affecting the lid fitting properly or causing other clearance issues.

I hope this helps some of you.

Simon

[Glenn2]

Originally Posted by grofus

Do you need to run a wire to ground from the ground pins also?

Yes, to U274 is the best place.

When I said insert regulators there, by regulator I mean regulator circuit, not just the three-legged item itself.
You at least need to add output decoupling capacitors, 100uF-470uF/16V is my recommendation, in addition to ground connections.
I always use a little bit of veroboard containing LM317/337, voltage setting resistors, decoupling caps.

[Malefoda]

Simon,
very nice that how-to series, nice pics!
Grofus, as Glenn said it's handy to work on protoboard.
Marantz CD63 & CD67 mods list

Matthieu

[SimontY]

Cheers.

For a beginner I think it's a bit much to be using separate boards and extra caps. It's much easier just to wire the regs in directly. The output caps are already on the board for you, but I usually add the odd extra input cap to make sure the regulator is happy.

Simon

[Glenn2]

Originally Posted by SimontY

The output caps are already on the board for you....

Not if you leave the resistors in the circuit, which is a good idea as it isolates the servos drivers from each other. These form RC filters with the caps at the drivers.

But basically, if you use the insertion points I suggested, you definitely need the output caps.

I think the big benefit of all of this is actually keeping the servo noise away from the rest of the player, i.e. less of it on the raw 10V supply for the rest of the player.

But if you are using the resistor points to insert individual regulators - so the existing caps are on the reg's output - then no you don't need any more caps.

[grofus]

Simon, thanks for the detailed info on fitting the regs. Glenn and Malefoda, thanks also.
I think I need to gen up on basic electronics, so I can "understand", rather than just copy. Anyone recommend a book ? Never realised how addictive this is! Cheers Steve

[Malefoda]

Maybe have a look at:
Ray's Audio Page
then:
Using 3-pin regulators off-piste: part 1
and Simple Voltage Regulators Part 1: Noise - [English]