Wah! It died!

[A.J. Franzman]

Hi, I noticed this thread and I thought I may as well post here in reguards to my 2 busted Woodys as opposed to create a new one.

Both switch on, but always on the screen is just a blank black screen. Both RF Modulators appear to be fine. The better of the condition of the two I did have working in the first place, I was working on the PC with it switched on with River raid in the slot when the screen got slightly darker (Not mistaking it for the colour change) and then went to black. Ive opened it up, cleaned out the slots, tried moving the cart slightly in the slot when switched on as this somtimes gets games to work on a Mega Drive, but to no avail. Ive tried looking up on google to see if I can find out what is directly to blame but all I get is junk. So with my first post I ask for your help, as being a 16yr old Student I have next to no money.

The RF modulator is not usually a suspect when the symptom is a blank black screen. It could be any of the ICs, but IMO probably not the TIA (the expensive one). Since you give your location as the U.K., I assume these are PAL units -- even if you wanted to ship them to me in the U.S.A., I don't work on PAL consoles. You'll need to fix it yourself or find someone in your part of the world that works on them. If you want to try to fix it yourself, in addition to looking for failed chips, you should also check the voltage regulator's output. But be aware that a bad IC can pull the voltage down, so don't replace it unnecessarily. A method you might use for diganosis would be to swap the chips from your bad unit into a known-good unit one-by-one to identify any bad chips, then put a good set of three into your console and measure the regulator's output. If you still have a black screen with three known-good chips and voltage between 4.75 and 5.25 V, then your problem lies elsewhere.

[Spirantho]

If it helps, I can fix it, but I tend to be rather busy so you may need to be patient.

 

I have about 40 2600s so spares aren't a problem for me. Let me know if I can help (I'm in the UK).

[sega2006]

I dont know which chip is which, but I am going to have to fix it myself as I cant afford to ship it any where, even just to the next town. The only working one I have is a jr and I dont want to dismantle it in case somthing breaks on that. If any member has a diagram detailing which chip is which then I may be able to find the faulty one, thanks for the help you have given me

[alex_79]

These pictures shows the boards of PAL consoles.

 

 

6 swicth model

 

4 switch model (This is actually a "vader" system, but I think that internally is the same as the 4-switch woody)

 

 

On AA archives there are schematics for the 6 switch and junior PAL, but not for the 4 switch. I hope this can help.

[sega2006]

Yep, it sure has.So now I know which bit is which, I can find out (Hopefully ) what is to blame and fix it

[sega2006]

Im going to have to get 2 new sets of chips as Im unable to test them with my Jr's chips are solderd in and I dont want to risk damaging them. Anybody have any idea of what it will cost me?

[A.J. Franzman]

Yes -- it will be cheaper to just buy another console on eBay, or maybe Spirantho will sell you one of his.

 

Most (or all?) Juniors have their chips soldered in, as do a few 4-switch woodgrain units and most Vaders (I believe).

 

If you're able to find some cheap chips, or a good console to diagnose exactly what's wrong with your other two, pay attention when removing the chips which end has the "U"-shaped notch -- it's different on some chips between the different console models. Usually once the chip is removed, you can see a matching notch in the socket or in the legend printed on the board.

 

Also, these chips are all highly static-sensitive and certain precautions must be taken to prevent damage when removing them or handling them when loose.

Edited March 12, 2007 by A.J. Franzman

[Spirantho]

I dont know which chip is which, but I am going to have to fix it myself as I cant afford to ship it any where, even just to the next town. The only working one I have is a jr and I dont want to dismantle it in case somthing breaks on that. If any member has a diagram detailing which chip is which then I may be able to find the faulty one, thanks for the help you have given me

 

I wouldn't recommend that unless you either a) know what you're doing or b) are willing to write it off when the repair operation goes wrong!

Old woodgrain Ataris are a real can of worms to repair because the wires inside them are old and tend to break off on the joining cable between the two halves. The Vader and Junior style is a lot easier but still problematic, and it really could be any number of things that's gone wrong - if you have duplicate chips and don't mind de/resoldering them you may be able to diagnose the fault, but even then it could be something like the 7805 regulator (I've had that produce a black screen as the power was enough for the modulator but not the ICs). If you have an oscilloscope it may make your life a bit easier, but the best debugging tool for repairs is simply another console so you can test chips.

 

One other thing - postage is cheap if you take the main board(s) out of the case and send them to me in an anti-static bag. Just let me know if I can help.

Edited March 12, 2007 by Spirantho

[sega2006]

I dont know which chip is which, but I am going to have to fix it myself as I cant afford to ship it any where, even just to the next town. The only working one I have is a jr and I dont want to dismantle it in case somthing breaks on that. If any member has a diagram detailing which chip is which then I may be able to find the faulty one, thanks for the help you have given me

 

I wouldn't recommend that unless you either a) know what you're doing or b) are willing to write it off when the repair operation goes wrong!

Old woodgrain Ataris are a real can of worms to repair because the wires inside them are old and tend to break off on the joining cable between the two halves. The Vader and Junior style is a lot easier but still problematic, and it really could be any number of things that's gone wrong - if you have duplicate chips and don't mind de/resoldering them you may be able to diagnose the fault, but even then it could be something like the 7805 regulator (I've had that produce a black screen as the power was enough for the modulator but not the ICs). If you have an oscilloscope it may make your life a bit easier, but the best debugging tool for repairs is simply another console so you can test chips.

 

One other thing - postage is cheap if you take the main board(s) out of the case and send them to me in an anti-static bag. Just let me know if I can help.

 

Thanks, I think I will be better off with your help. I think I may have a couple of Anti-Static bags lying around from a graphics card. Do you want anything for repairing the boards? It may be a week or so before I can send anything as I didnt work this Saturday so I havn't got any cash.