Finally, an affordable CD Transport: the Shigaclone story

[ralphfcooke]

The platter height on a lot of these cheap mechanisms is simply a matter of pulling or pushing the platter ring on its interferance fit shaft.
I was given a quite expensive Sony unit recently because it was 'broken'; all it needed was the platter raised by about a millimeter to get it working perfectly

[Peter Daniel]

The platter ring is glued to the shaft, so without special tooling it's hard to move it. Besides, it should be self adjusting (fixed shaft length, platter pressed to the end)

[kevinkr]

Originally Posted by JC Fardo

Can I adjust the platter height ??

JC

Yes, you just need to know what it should be to a convenient reference point. If you purchase a replacement mechanism you can measure from the rail or mechanism chassis to the platter on that mechanism and check that it is the same on the old mechanism..

The platter can be carefully pulled off and replaced - and I have done this, so it can be moved on its shaft relative to the laser. You need to grip the motor shaft with needle nose pliers before pushing or pulling on the platter. If you have not disturbed your platter height somehow then you probably need to look elsewhere for the problem.

Make sure there is nothing amiss with the reworks you have done to the board.

[kevinkr]

Originally Posted by Peter Daniel

The platter ring is glued to the shaft, so without special tooling it's hard to move it. Besides, it should be self adjusting (fixed shaft length, platter pressed to the end)

Mine are all interference fit, no glue in sight. Platter is pressed nearly, but not quite to the end. Incorrect height settings caused by tinkering have caused me some minor issues quickly resolved by moving the platter slightly up or down on the motor shaft as necessary. Shaft must be clamped and no force applied to the motor or it will be damaged. (From experience)

[JC Fardo]

Yes, thanks so far for all those valuable hints

I found this tool after all this time, can be used in the future to replace the original platter and puck

HobbyKing Online R/C Hobby Store : Turnigy 25mm Flywheel Removal Tool

JC

[Peter Daniel]

Yes, the proper tool is necessary, here's what I was using: Finally, an affordable CD Transport: the Shigaclone story

[Henjo Edel]

Design dimensions and tolerances in a previous post.

http://www.diyaudio.com/forums/digit...ml#post1747150

Henjo

[uncle_leon]

Hi guys, I don't think anyone has done this before
LCD incadescent bulb mod:


I always loved the style of VU meters on my old NAD 3030 amp, backlit with actual little bulbs, so I swapped the LED in the display board for a 12V subminiature bulb (got it from Maplin, cost me a whopping £1 or so).

At the minute I'm feeding the bulb directly off the transformer, which makes it quite bright (I think I'll add a pot for changing brightness) - this also has an added bonus of bringing the transport "alive": it dims a bit on each seek or stop, it also dims intermittently when the reader is struggling with a scratched CD, or generally does something other than read or idle (I'm guessing this is because of poor regulation of the boombox transformer). In any case, I like the effect very much

The black thing covering the light is aluminium foil - the bulb didn't quite fit in the LED hole, so I couldn't use the stock plastic "cover". Cutting a bit of plastic should easily solve this, I just didn't get round to doing it yet.

Also, I took out the white piece of plastic sheet from behind the LCD (the one acting as a light diffuser of sorts) - I think it makes the display look boring. Without it, it looks kind of old school with the visible vertical glass "stripes", which I like.

Oh, and in case anyone is wondering - the bulb does get pretty hot, but not terribly so, and it doesn't seem to melt anything around it, or smell, or cause any other problems. I've had it running constantly all day today and all is fine

[woodturner-fran]

Did any one else try using the RF attenuators? Peter?

Well worth it - and you can dispense with the 300/100 resistors if you use a high enough dB attenuator.

Fran

[uncle_leon]

I'm pretty sure the resistors are there to create a 75Ohm impedance path, and to reduce the digital output level to the textbook 0.5mV... This has nothing to do with RF interference reduction (not to my limited knowledge anyway).

Also, I'm quite sure Peter wrote a while ago that he tried and didn't like RF attenuators (although I would wait for his confirmation on this). From memory, he never liked any "forced" forms of noise suppression, like power conditioning, chokes etc.

Personally, I'm a big believer in reducing RF interference by... moving devices that cause it away from your HiFi

In any case - if it works for you, then go for it, why wait for someone else's opinion?