POT Readings for Saturn.. Helpful or Bogus?

So I picked up a Saturn on eBay in exchange for my first born, and of course it has a dud laser. Well, it did INITIALLY SPIN, and play Audio Tracks from a Sega CD game. Considering the Saturn is backward compatible, I couldn't find my copy of Virtua Figher so I tried to use Monkey Island for Sega CD. I could get Audio, but no Video.

Long research on the values of the proper POT settings for a Saturn laser came back with very little, but generally that you want the POT over 650 Ohms, but not higher than 720 Ohms. Here's where things get iffy, my POT readings read about 70 Ohms, so I figured that the correct POT setting was mislabeled as 650-720 Ohms, and should have been 65-70 Ohms. Needless to say, I can adjust to the 'recommended' values, but can't get the Laser to spin at all anymore.

Onwards, I've read on this Forum that values on a POT can vary wildly from different Systems. To have a system that is 600 Ohms off... does that indicate I am using a different model Saturn than was recommended (the above 650 recommendation was from a PAL version, I'm using NTSC.) A few members of this Forum are inclined to believe that you need an Oscillator to properly adjust a POT.. which might explain why my recent endeavors in fixing Gamecube lasers and this Saturn laser has come out with poor results.

If someone can shed a bit of light on if POT measurements can really vary that much, and if reading a POT is completely useless via multimeter or not.. any help or guidance is of course appreciated.

 

The Saturn can play Sega CD games? This is the first I've heard of this.

 

I don't think it's backward compatible...

From http://www.consoledatabase.com/faq/segasaturn/segasaturnfaq.txt

 

It's not backwards compatable with sega cd. you should set it back to what it was and try a saturn game. you can damage the laser by adjusting too far so hopefully it still works.

 

As I've said time and time again on the forum, this is not how you adjust a laser diode. You're right in assuming that using a multimeter is pretty useless, as is using other people's readings.

You need to check the RF level to see whether the diode needs replacing, then adjust the focus error bias and gain. It needs an oscilloscope and a special test CD (which, of course, isn't available any more).

Other consoles used even more equipment to calibrate!

 

OK, so I had read somewhere that they are backwards compatible... which really bothers me since I probably just ruined a perfectly good Sega Saturn. I can't get the Disc to spin after adjusting the POT, and even though I remember where it was originally... it just attempts to read but fails in spinning. What a bummer.

Anyways, I don't have an oscilloscope, or really the know how (or patience) to do all that. I suppose to check the diode (resistance via RF?) is what an oscilloscope is for? From there, a test disc would help exactly how? Anyways, interesting read.

Last question: On eBay the sell replacement Saturn lasers which also seem to be compatible with 3DO's and Jaguar systems. I have a few 3DO's with bad transistors, would I be able to swap lasers in to the Saturn? Thanks

This Seller has a Laser for a Saturn, the Listing Reads:

[h=1]NEW OPTICAL LASER LENS PICKUP for GOLDSTAR 3DO SEGA SATURN[/h]
Thing is, I have a couple 3DO's that have died on me, something internal and I gave up on a while ago. My Laser for my Saturn needs replacement. Can I just swap, or perhaps the Laser which is being Sold on eBay is specially formatted for both System? Just an inquiry, anybody know? Thanks

 

have you ever tried cleaning the lens of your sega saturn? the disk drive was made really well and close to never dies i bought my sega saturn faulty which had problems reading disks and i did have to clean the laser a second time when everything was put back but it worked, also depending on the price maybe i could buy one of those 3do's especially if it's pal which i doubt that it is

 

I've merged your two topics together, simply because you've asked the question in your previous thread, then made a new topic and asked the exact same question.

People will reply when they have an answer, don't create new topics because you haven't received an answer in 24 hours.

 

Sorry I hadn't thought a separate topic would hurt, but I suppose it is a repeat question.

Yes of course, the problem is that I have already adjusted it if you've read the post carefully you might see that, but anyways I fear that I have pushed the limits of the Laser too far, since now I get no readings at the same original OHms frequency.

 

Yeah and it's getting worse with time due to the necessary equipment bit. At least with the PS1 you can get away with dicking around with it and getting somewhere but I've never gotten anything from most CD based consoles from the 90s. An oscilloscope isn't remotely hard to get but the test discs are.

 

And I've merged all the double posts.

Slypty, please try to use the edit and multi-quote buttons rather than double posting

 

It'd be nice if there was a floating burnt CD file for this type of CD.. Hard modding a System with a broken CD, then booting it up to read a CD or DVD-R/RW through the burnt copy might make things easier.

What does multi-quote do?

 

Allows you quote various posts into one like I have done in this post.

Some text goes here.

Some more text goes here.

 

Yay, with a little bit of luck and one last try, I managed to find the correct POT setting. I just tweaked the concentration up a few notches and found my copy of Virtual Cop. Good stuff... now to find a decent mod so I can play my Japanese Saturn games. BTW do not attempt to exchange Lasers from a REAL 3DO.. they built the surroundings of the Laser like it's an A-Bomb.