Donkey Kong Troubles

Just picked up a non-working DK cab with a 4 board set for a friend of mine. Upon powering up the screen comes up bluish black with vertical white lines and the sound blasted an annoying sound. After scouting for info, we notice dip 8 was off(cocktail), switched it on(upright), re-energized and the sound disappeared never to return again? Still no screen. Figured I throw out a few pics of questionable areas for some feedback. 1. there appears to be a transistor missing. 2. one of the large caps on the monitor board appears warped on the outside. 3. there is a shoddy looking daughter board soldered on with one wire containing three pots as well as other components.
The boards have a sticker on them that says it was tested and working in 2000 by Eldorado Games. This cab was bought from someone who got it in a bulk buy, so no other info is available. Thanks for any input.
-Scott

More pics:
Missing transistor:


Bad Cap?:


Daughter board front:


Daughter board back:


Daughter board solder connection:

might want to contact eldorado games. http://www.eldoradogames.com/

forgot who, but a member here used to work for them and highly recommended their service for board repair.

You're gonna be just like that guy on The King of Kong.

Neo Alec said:

You're gonna be just like that guy on The King of Kong.

Click to expand...

The thought of a potential kill screen gives me a raging hard on.

Looks like your board doesn't have any video output. Those lines you see are retrace lines on the monitor. Someone has cranked up the screen control on the high voltage transformer.

Check your power supply to make sure all the voltages are there. Replace the transistor with the proper replacement and fire up the game again.

If you need a manual with schematics I may have it here or you might find it out on the crazykong.com website.

If you don't feel like tackling it yourself you can always check on the KLOV.com forums for folks that repair those old Nintendo games.

RJ

Cleaned the shit out the pcb's, checked power supply and the 12vdc was at 14.7, brought it back to 12 and no change. What should I be checking for as a video output? Is it just a voltage from the R,G,B, or Sync to ground?

LameKat said:

Cleaned the shit out the pcb's, checked power supply and the 12vdc was at 14.7, brought it back to 12 and no change. What should I be checking for as a video output? Is it just a voltage from the R,G,B, or Sync to ground?

Click to expand...

As CM said, there appears to be no video drive, that shitty looking sub board may have something to do with RGB drives going by the pots. Does the IC mounted to it have 5 volts supply. I dont know what it is for (maybe a video drive amp) but perhaps a wire has come loose ?
What happens if you take direct RGB and sync from the edge connect to the monitor.

Dont worry about the 12 volts, thats only to supply the audio output stage.
Make sure the 5 volts is correct at the boards edge connect.

Nintendos have inverted video signals compared to other games... so if it doesn't have the original Sanyo monitor (20EZ I think...) then you need that little board.

Try the folks over at the klov.com forums. There are a few DK gurus over there.