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[CLD-97] The CLD-97 alignment project
https://forum.lddb.com/viewtopic.php?f=53&t=7463
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Author:  pbiancardi [ 29 Nov 2017, 12:56 ]
Post subject:  [CLD-97] The CLD-97 alignment project

So I bought a McIntosh MLD-7020 (CLD-97) that needed a new laser pickup, I brought it to a local McIntosh authorized service center that claimed they could do the work but when I got it home it became clear that they did not know how. The pickup has been swapped by the service center (with one from a 2080 that I provided) and it will play after 30-45 seconds of searching but with no chapters so I know everything CAN work but needs to be aligned. In messing with it I did get it to play once with chapters so I am very confident that it can work.

In a perfect world I would send out to Kurtis but he is busy so I figure rather than continuing to bother him with email questions (thanks for always answering Kurtis) I will post here and maybe we can all learn together. We are fast running out of options so we are forced to learn ourselves if we as a community want to keep these players running. This might take a long time but hopefully by the time I am done this thread has a lot of information in it that everyone can use (since I am starting basically from scratch maybe this can help others that are also). I will document my efforts with pictures and video in the hope that it ends up helping others in the future. If I can get this one working I will do a similar thread for the 704 type players which by all accounts are much easier to align.

I have -

1. Pioneer service remote.
2. 8" Test Disc GGV1239.
3. CLD-97 service manual
4. McIntosh MLD-7020 in need of alignment

I need -

1. Oscilloscope / Waveform Monitor
2. Skill (which I can hopefully develop)

So question #1 is which oscilloscope do I get? The guy that did all of the CLD-99 mods on YouTube has a waveform monitor is that what I need or an oscilloscope?

Options -
https://www.ebay.com/itm/Tektronix-1740 ... SwbiFZQa8Z
https://www.ebay.com/itm/GW-Instek-GDS- ... 1438.l2649
https://www.ebay.com/itm/GW-INSTEK-Osci ... 1438.l2649

Are any of these appropriate / does analog or digital matter?

Question #2 is the coarse / fine grating adjustment, I cannot for the life of me figure out where the adjustment point is? I see in the service manual where it shows and I have the old pickup in my hand to look at but I cannot figure it out? Kurtis has told me its like an arm with a slot but I have been poking around the thing for hours and still cannot locate it. The other adjustment points seem very easy to get to but this one I cannot figure out, here is pic from service manual -

Image

Author:  zoidbergforever [ 30 Nov 2017, 14:31 ]
Post subject:  Re: The CLD-97 alignment project.

I wouldn't even go near the coarse/fine grating unless absolutely necessary. In any case it would be good to know how to if needed.

Author:  pbiancardi [ 30 Nov 2017, 20:29 ]
Post subject:  Re: The CLD-97 alignment project.

zoidbergforever wrote:
I wouldn't even go near the coarse/fine grating unless absolutely necessary. In any case it would be good to know how to if needed.


Sounds like its necessary? It is the first adjustment listed in the service manual, are you suggesting I do the other adjustments first? The issue is I do not get chapters if the disc does play so how would I adjust anything without being able to find frames on the test disc?

Also this is where Kurtis told me to start...

Author:  zoidbergforever [ 30 Nov 2017, 21:01 ]
Post subject:  Re: The CLD-97 alignment project.

If Kurtis suggested you start with it then fair enough. Just keep in mind that if it's out of alignment it won't work at all. You'll need all the alignment gear

Author:  pbiancardi [ 01 Dec 2017, 14:30 ]
Post subject:  Re: The CLD-97 alignment project.

zoidbergforever wrote:
If Kurtis suggested you start with it then fair enough. Just keep in mind that if it's out of alignment it won't work at all. You'll need all the alignment gear


By all the alignment gear you mean scope, test disc, and service remote correct?

Author:  happycube [ 01 Dec 2017, 18:18 ]
Post subject:  Re: The CLD-97 alignment project.

Generally the older the player, the more jigs you need (when you get to 1995 or so, you can get away without anything else!) - but that's detailed in the service manual.

Author:  pbiancardi [ 01 Dec 2017, 19:28 ]
Post subject:  Re: The CLD-97 alignment project.

happycube wrote:
Generally the older the player, the more jigs you need (when you get to 1995 or so, you can get away without anything else!) - but that's detailed in the service manual.


Maybe that is why I am struggling to understand how to adjust the coarse grating....especially with an 8" disc playing...

Author:  pbiancardi [ 10 Dec 2017, 18:23 ]
Post subject:  Re: The CLD-97 alignment project.

So the project is basically dead because I got it working without a scope, here is what I did -


Started with centering adjustment as Kurtis has described (half way between points where a CD will stop playing) and got CD playing with chapters.

Next moved to tracking balance and trial and error until it would read an LD with chapters (this was huge breakthrough, couldn't get it to do this before).

Digital audio was distorted so fine tuned RF level up until digital was clean.

At this point it would not get to the end of a side without huge crosstalk so I adjusted tilt balance (with disc playing) until everything seemed to play clean.

Now it appears to be playing clean side a and side b, verified AC3 is working as well as digital audio.

Author:  rein-o [ 10 Dec 2017, 22:24 ]
Post subject:  Re: The CLD-97 alignment project.

pbiancardi wrote:
So the project is basically dead because I got it working without a scope, here is what I did -


Started with centering adjustment as Kurtis has described (half way between points where a CD will stop playing) and got CD playing with chapters.

Next moved to tracking balance and trial and error until it would read an LD with chapters (this was huge breakthrough, couldn't get it to do this before).

Digital audio was distorted so fine tuned RF level up until digital was clean.

At this point it would not get to the end of a side without huge crosstalk so I adjusted tilt balance (with disc playing) until everything seemed to play clean.

Now it appears to be playing clean side a and side b, verified AC3 is working as well as digital audio.

Thanks for posting this, I'm sure it will help some in the future.

Author:  zoidbergforever [ 11 Dec 2017, 00:51 ]
Post subject:  Re: The CLD-97 alignment project.

Great job! Just in time for Christmas :)

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