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Author Topic: Thompsons Dvd Drive Pot Tweaking  (Read 44 times)

illastic1

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Thompsons Dvd Drive Pot Tweaking
« on: May 13, 2004, 03:02:00 PM »

I am trying to tweak my thompsons dvd drive to read better but the only tutorial that seems to exist on it is hardly explained in great detail and i am new to this.

Here is the tutorial: http://www.xbox-scen...es/dvdtweak.php

it says "looking from underneath, on the laser unit itself, you will see a pot on the bottom left of the pcb, Scratch the resin off CAREFULLY, the pot can be easily damaged."

i dont know what is meant by a "pot" and i can't see any resiny substance around vital parts..only pink glue round the some screws. Could someone please explain this in more detail? as am new to this.

Thanks
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opjose

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Thompsons Dvd Drive Pot Tweaking
« Reply #1 on: May 13, 2004, 07:23:00 PM »

I'll be the first to caution you to AVOID doing this.

If you see any improvement it will be so marginal as to not be worth it.

There are a long list of reasons why you should not do this, including the sheer amount of people here who have ruined their drives.

If you are trying to use burned media and are having problems, look elsewhere for the cause.

DVD-R's work just fine.
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opjose

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Thompsons Dvd Drive Pot Tweaking
« Reply #2 on: May 14, 2004, 02:44:00 AM »

Sorry, I haven't seen much of a difference, especially enough to warrant advocating this rather delicate change to newbies who are trashing their drives right and left.

I've player with 20+ Xboxes vis-a-vis reading DVD-R disks, even the super cheapo, purple no-namers.

If the disk was burned burned properly, ALL of the 20+ machines I tried would read the disk flawlessly WITHOUT the pot tweak.

This includes 1.0 units with Thompson drives thru to the latest 1.4 models.

I haven't had my hands on anything later than 1.4 yet, so I can't vouch or denounce their performance.
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opjose

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Thompsons Dvd Drive Pot Tweaking
« Reply #3 on: May 17, 2004, 05:23:00 PM »

QUOTE (worse1 @ May 17 2004, 11:34 PM)
It didnt work for me, so i just went ahead an purchased another dvdrom. Hope it works for you!!!!

Yeap, another drive ruined, thanks to this tutorial.

It's simply not worth doing.
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clown88

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Thompsons Dvd Drive Pot Tweaking
« Reply #4 on: May 18, 2004, 01:00:00 AM »

Mine just died too...
DON'T DO IT!!!
Its not worth it.
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Blackfly1976

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Thompsons Dvd Drive Pot Tweaking
« Reply #5 on: May 18, 2004, 03:09:00 PM »

I'd just like to add to this thread (despite my drive being Philips) that pot tweaking made an enormous difference in my experience, also that whatever I did the drive has not been in any way damaged (despite it not working properly whilst using certain resistance values of course).
Interestingly, in order to get CDRs to work, CDRWs stopped being recognised (and vice versa). I personally think this may be a reflectance interference issue but have no clue really, anyone have any ideas?
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Killazincorp

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Thompsons Dvd Drive Pot Tweaking
« Reply #6 on: May 18, 2004, 03:22:00 PM »

Ive dont this to my thompson drive as well hoping that it would save me some cash so that i didnt have to buy a samsung drive. None the less i didnt break the DVD Rom doing this mod and there was a slim improvement. The drive will read some of my burned media better but as far as it allowing me to read data discs or backups of DVD movies, forget it same old BS. So to make a long storey short I did it and did see a slim improvement but not enough to change much and in the end felt satisfied to have gotten the courage to do such a thing and get some experience


P.S.
This was the first mod i ever did, never had opened the xbox prior to this mod.
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opjose

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Thompsons Dvd Drive Pot Tweaking
« Reply #7 on: May 18, 2004, 09:37:00 PM »

QUOTE (Blackfly1976 @ May 18 2004, 11:09 PM)
I'd just like to add to this thread (despite my drive being Philips) that pot tweaking made an enormous difference in my experience, also that whatever I did the drive has not been in any way damaged (despite it not working properly whilst using certain resistance values of course).
Interestingly, in order to get CDRs to work, CDRWs stopped being recognised (and vice versa). I personally think this may be a reflectance interference issue but have no clue really, anyone have any ideas?

The POT tweak does NOT adjust the laser strength as some have erroneously speculated.

It adjusts the noise floor of the optical pickup.

The "Noise" is fairly fixed, dependant upon the media which is inserted.

A "good" signal should produce output above a certain level.

Moving the pot adjusts this level.

If you move it too far one way, then the drive will read less effectively, as it will reject too much.

Move it too far the other, and it will pick up too much noise, which will cause misreads and slower performance.

-IF- you DO get an improvement with some media, you are sacrificing read speeds to get it.

That is, now the pickup is more sensitive to what it would have rejected as noise. When it picks up an error in a block (which it might have not done before) it will now seek and reseek more often.

It's a VERY VERY fine line with only tiny performance increments.

Not really worth doing, unless you are quite prepared to purchase a new drive when things go awry.
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FreqNasty

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Thompsons Dvd Drive Pot Tweaking
« Reply #8 on: May 23, 2004, 05:32:00 AM »

QUOTE (worse1 @ May 18 2004, 12:34 AM)
The resin is the pink stuff. You have to be real careful not to scrape too hard or you will knock the POT off the Lense. Once you remove that pinkish resin, there will be a screw (phillips) you will need to turn that baby to the left (counter clockwise). But before you do that you will need to get the readings. (see the tutorial).  It didnt work for me, so i just went ahead an purchased another dvdrom. Hope it works for you!!!!


Man those groove in that pot are so small..i can barely make out that its a philips..the resin is so hard to get off completely so its still dirty and obstructing a good view of it.
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opjose

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Thompsons Dvd Drive Pot Tweaking
« Reply #9 on: May 23, 2004, 05:42:00 AM »

QUOTE (Lugnut @ May 19 2004, 01:22 PM)
However occasionally i run across a tommy that has a resistance value of 2500+ ohms (seems like the oldest of the xbox's have this), and these seem to be the drives that gain the most from this tweak. I simply set them to about 1400 ohms.  

Actually that explains a lot.

Also why (few) people have seen gains, whereas the majority do not.

Someone must have been asleep at the wheel in the QA department.
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FreqNasty

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Thompsons Dvd Drive Pot Tweaking
« Reply #10 on: May 23, 2004, 05:45:00 AM »

btw..do u turn the pot counter clockwise with the laser facing downwards or upwards?
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opjose

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Thompsons Dvd Drive Pot Tweaking
« Reply #11 on: May 23, 2004, 05:48:00 AM »

Eh you should really do this with a meter connected.

That way you know if you are turning it in the wrong direction or too far.
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Lugnut

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Thompsons Dvd Drive Pot Tweaking
« Reply #12 on: May 23, 2004, 07:56:00 AM »

if you think about it counter clockwise is counter clockwise no matter which side is facing up lol,
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FreqNasty

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Thompsons Dvd Drive Pot Tweaking
« Reply #13 on: May 28, 2004, 09:50:00 PM »

yeh lol

that screw is hard to turn, i don't even know if its turning. I cant see any grooves for a screwdriver to get a grip on it. Anyone know if a philips head will turn it?
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