Atari Middle Earth issues

[thebman80]

Yeah I have no idea why I'm not getting the voltages out of the power supply yet I'm sure its going to be a total rebuild. Which also isn't that much a few resistors, diodes and transistors. I replaced the capacitors and most of the diodes and a few of the resistors. The problem is there some weird transistors and diodes I don't have and most of the resistors values I do have there just a higher wattage I don't have. So fun time ordering even more parts that I will sit on until I need in the future. It's getting to the point that I'm surprised when I still need to order more transistors and resistors since I have so many different kinds.

Oh so it looks like the blue wire is the bottom the red wire middle and white wire is on top of the J14 connector. I think the PCB might be silk screened wrong will have to double check on that later.

I know the manual was wrong about the main fuse block on the power brick that was a total misprint.

Here is the order their suppose to be this is from the pinwiki and is correct:

This is for all games EXCEPT for the Atarians that is different.

All other games

Position on strip Designation Circuit Protected Fuse Rating Notes Uppermost fuse F6 Audio 2 Amp fast-blow

F5 Displays 0.5 Amp slow-blow

F4 Displays 0.5 Amp slow-blow

F3 Lamps 15 Amp fast-blow

F2 Logic 7 Amp slow-blow

Bottom fuse F1 Solenoids 15 Amp fast-blow 5 Amp slow-blow substitution recommended.


This is from the actual manual and is incorrect. It says F1 starts at the top and goes down to F6 when its actually the reverse F1 starts at the bottom and F6 is at the top. So beware changing your fuses using the manual.

 

[thebman80]

Have an update today, I ordered a bunch of parts from china to rebuild the HV 90v power section on the main power PCB. I ordered everything like 4 weeks ago and the last part showed up in the mail today finally. So I went and shotgunned all the 90v section on the power PCB turned on the game and got this.

Now the coin display was out but after unplugging and plugging the connector on and off it finally came on. Problem now is that all the displays are on and read all 8's and never change. Credit and ball displays work great once the game is started. The score display shuts off the 2nd through 4th player scores like it should when you start a game. But it wont keep score just reads all 8's. I'm thinking I might have some sort of logic problem on the main PCB for the score keeping.


Here's what it looks like once the game starts up:

 

[thebman80]

Plugged in my spare display boards with the display glass pictured above since I only have one and now it works. Well almost it counts the score but it doesn't cycle through the 1st through 4th players and there is a lot of shimmering. I think I may have to recap the power caps for the displays. I may just figure out what IC is bad and use my original displays since it runs a lot more stable.


Fun fact as soon as I got the displays working and played a few games the out hole started to lock on (face palm). I will check the transistor for it a little later just cant catch a break here lol.

 

[thebman80]

Ok I found the problem seems that only the first player score was effected once I started up all 4 players 2 through 4 scored fine. This basically narrowed it to only one possible chip that could have been bad location C5 under the main display.

After replacing that chip from the one display PCB that flickered this one now operates fairly solid. I believe the capacitors are probably shot on that flickering display they are 2 years shy of 40 years old. I Plan to replace all the Capacitors on both displays just for routine maintenance. Hopefully they will last another 40 years then it wont be my problem lol.

Now I have to order a rubber kit, clean all the contacts and take apart and clean everything on the playfield and wax it.

 

[trueno92]

Bumping this as I have been working on one and it displays 88 88 on ball and credit but will not let me coin up.

Score displays look ok but go out after 2 mins.

Coin switch also doesn't register during the switch test, and I'm not sure what else to try...?