Jaguar CD laser potentiometer impedence setting?

[Gunstar]

I'm in the middle of attempting repairs to a Jaguar CD unit, I actually had it working for a while earlier today, but the laser isn't reliable at reading the discs. I think the potentiometer needs adjusting (brighten the laser a tad). But I need to know what the proper impedance setting range is supposed to be for the Jguar CD laser eye. I repaired my Xbox with a similiar problem about a year ago, the factory setting was 1700, but adjusting it to somewhere between 1500-1000 got it working properly. But The Xbox is DVD and the Jaguar is CD laser eye, so I'm sure the impedance settings are different. Anyone know what the proper setting or "range" is for it?

[guitarmas]

I'm in the middle of attempting repairs to a Jaguar CD unit, I actually had it working for a while earlier today, but the laser isn't reliable at reading the discs. I think the potentiometer needs adjusting (brighten the laser a tad). But I need to know what the proper impedance setting range is supposed to be for the Jguar CD laser eye. I repaired my Xbox with a similiar problem about a year ago, the factory setting was 1700, but adjusting it to somewhere between 1500-1000 got it working properly. But The Xbox is DVD and the Jaguar is CD laser eye, so I'm sure the impedance settings are different. Anyone know what the proper setting or "range" is for it?

 

I usually try to go for 100% potentiol, but I never seem to get it right.

[Gunstar]

There's a prerequisite of actually being smart before you can be an effective smart-ass.

[atarifan49]

According to Atari's test procedures there is a current check. Here is text from the specific procedure for the laser current.

 

Laser Current (test # 4.3.4)

Voltage at TP60 (R24), focus off = (your measurement A)

Voltage at TP60 (R24), focus on = (your measurement B)

Calculate current: Ilaser = (B-A) / 4.7

Verify that Ilaser < 90 mA.

 

I'm not sure how you would control the focus on/off mention in the procedure. But this seem to be the only procedure dealing with the CD laser. Unfortunately the schematics don't cover the CDM12 mechanism. The above test point should be near U4.

 

But if you can manage to get a reading while the laser is moving up and down and one when it stops this might get the results your looking for. Then its just a matter of doing the math and hopefully the pot on the mech can adjust this current.

 

Good luck.

 

Glenn

[EmOneGarand]

I'm in the middle of attempting repairs to a Jaguar CD unit, I actually had it working for a while earlier today, but the laser isn't reliable at reading the discs. I think the potentiometer needs adjusting (brighten the laser a tad). But I need to know what the proper impedance setting range is supposed to be for the Jguar CD laser eye. I repaired my Xbox with a similiar problem about a year ago, the factory setting was 1700, but adjusting it to somewhere between 1500-1000 got it working properly. But The Xbox is DVD and the Jaguar is CD laser eye, so I'm sure the impedance settings are different. Anyone know what the proper setting or "range" is for it?

Try one of the PC-Engine forums, while the cd assembly for the Turbo Duo is slightly older the rating for the pots isn't too far off. The pots with the DUO lasers have the same problems as the Jag CD so it's good place to start.

[Gunstar]

Thanks guys! I'll check into both of these options.

[Symmetry of TNG]

iirc from DC laser modding its NEVER more than +-10% from original value anyway..

Overturning it will probably kill your laser diode & it will stop Lasing...

 

Good luck with the tuning.. and if you get a result plez tell us your findings =)

 

/Sym