PAL Vader - the saga continues... Missing C201, 30min then OFF?

[Microswitch]

Right-o

 

 

So... retro gaming was never supposed to be easy.

 

Continuing on from my previous thread:

 

http://atariage.com/forums/topic/249036-pal-vader-comp-mod-getting-scrolling-interference-pics-ideashelp/

 

All was working well... or so I thought then after 30min of gaming everything stops working, all carts tested, no sound, no picture? Leave it off for about an hour and then everything works fine again, crazy stuff!

 

I should note that, I've replaced the voltage regulator and 2x of the 3x caps with the following (C201 is missing, I'll explain)...

 

C243 = 2200uf 16v
C214 = 4.7uf 35v
C201 = "

 

On my Rev 6 Vader board C201 seems to be completely missing (see picture)... with a nice neat connector in place making me think that this is how it left the factory, intentionally missing?

 

I checked Atari domestic field service guide: http://www.atariguide.com/pdfs/atari_2600_vcs_domestic_field_service_manual.pdf

 

PDF (page 24) shows Revs. 1-13 as having C201 in place... my question is: does anyone know if I should cut the trace and just put C201 in?

 

Could that be causing the 2600 to turn off?

 

My other thoughts are to resolder/reflow the cartridge connector points, perhaps something is expanding with the heat and a bad solder joint is failing.

 

Who knows?

 

I guess it could be my power supply but these things usually either work or don't work at all.

 

Any thoughts are most appreciated.

 

 

 

 

[+Stephen Moss]

I am not certain that trace you indicated is a replacement for C201, tracing it to when it connects would help indicate its purpose but I think it is just a link bridging a track on the underside of the PCB, although the lozenge shape next to it look more like a crystal that could be where C201 is meant to be. I would be suprised if it was removed as part of a design revision as in the circuit diagrams I have seen it is a 4.7uF that is part of a CR time delay for the Reset line of A200 (6507) that holds A200 in reset for a brief period to allow the power supply to stabalise.

 

In any event even with it removed it should not cause the problem you are facing which is more likely to be a power/dry joint issue.

If you have access to a multi-meter I would measure the input and output voltage of the 7805 regulator when the unit goes wrong, that would help to indicate if the problem is the power unit, 7805 or lies elsewhere.

If you are getting around 9V DC into the regulator and 5V DC out when the problem occurs try looking at my post in http://atariage.com/forums/topic/246217-help-troubleshoot-2600-resetting.

If you are still getting around 9V DC into the regulator but around 3 volts out of the regulator then something is drawing too much current and the regulator has shut down.

If you are getting less than 9V into the regulator then the power unit could be the problem.

 

[alex_79]

That 2600 service manual is for NTSC models. Pal boards like yours have a different layout so you cannot use that as reference. Unfortunately, there aren't scans of service manual for PAL 2600 available.

I missed one a while ago on ebay for the PAL-B/G 2600/2600A/2600Jr (The most common PAL standard used in most european counries). There should be also manuals for PAL-I (used in UK and Ireland) and SECAM versions, as well as PAL-N and PAL-M used in Latin America (actually the PAL-M one can be found online, but that version is completely different from the European PAL version).

[Microswitch]

 

Arrrrrr yes... PAL vs. NTSC board revisions that would explain it, it's always so obvious after someone tells you. Thanks alex_79, shame the PAL manuals aren't online.

 

 

Cheers Stephen, that's a great trouble-shooting post you linked to... I got small kids and not much spare time so highlighting the most probable causes is a big help! I'll post back once I get it working (prob a week or 2).

 

 

I'd like to say that this is one awesome community, very helpful... I spend most of my time in Commodore land over at the Lemon 64 forums (username: Addicta Balls) they're a great bunch too, I urge you to check them out if you ever need any hardware help:

 

http://www.lemon64.com/