Donkey Kong Junior White Screen

ev9d9

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Except for phosphor burn in on the display my CRT is just white. I have no audio or game play. The coin mech's dont click ect. I found this on another site just didnt know if there were any other options.

Problem: White Playfield, no graphics

Solution: Replaced both ECL RAMS (HM10422) at 2E & 2F on the Video Board

If so where do I get the RAM chips or should I just replace the board? Any help would be appreciated. Thanks much, Tim
 
If its got a Sanyo Monitor , the colors are reversed .

So if its a white screen that means its really a Black Screen , its getting no video signal from the game PCB .

Sounds like something is unplugged , or if nothing is working , you don't have power to the PCB game board .
 
Sweet. Trouble shot to the power supply. Have 100V from transformer going to power supply then somewhere I lose it. There are 2 boards in it. No blown (visable) fuse, caps, resistors, diodes, or damage. Thinking of resoldering any thoughts?
 
I had cold solder joints on my power supply where the game's wiring plugged in that caused this. Resoldering the input headers fixed it.
 
Audio Blasting

Awesome guys thanks, got a new power supply and it works now but.... Now the audio is squealing loud and the volume is blasting. This would work out great in a bowling alley but not in my living room. Any ideas what to do? I turned down the sound board but it goes off and the squeal is still there.
 
The only volume control I found is on the V-Hold /brightness board next to the CRT.... Is there one on the main board too?
 
Annoying Buzz

Pot is bad. When I twist it (as if I'm ripping it off the board) the volume goes to a reasonable level. I still have that annoying loud buzzing noise that over powers the music. Any Ideas? I'm thinking a ground wire somewhere maybe
 
Pot is bad. When I twist it (as if I'm ripping it off the board) the volume goes to a reasonable level. I still have that annoying loud buzzing noise that over powers the music. Any Ideas? I'm thinking a ground wire somewhere maybe

Replace the pot and recap and replace the transistors on the audio amp. You will still have some hum, but capping it will fix the loud hum. - Barry
 
Is the audio amp the same board that the pots are on or the one above it that the 3 wire harness goes to? Also which capacitor? I wonder if it would help if I took a pic
 
Is the audio amp the same board that the pots are on or the one above it that the 3 wire harness goes to? Also which capacitor? I wonder if it would help if I took a pic

It is the small auxiliary board attached to the monitor chassis, buy Bob Roberts deluxe cap kit, it includes two transistors also.
 
Here is a picture

IMG_20110802_061836.jpg
 
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