Donkey Kong PCB Issue

VertexGuy

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Everything works dandy except when you first power on the machine it makes the JUMP noise, the jump noise continues to oscillate in the background while the machine is on.

I read somewhere the cause might be..
transistor Q4 on the CPU board

I dont have schematics, what it looks like, the rating or even sure if this is whats causing it.

Anybody ,, please.

Having bad luck with PCB's over the last month.. I just want this one to work .
 
I had the same issue with my 4 board, though I think q4 might be in a different spot. Anyways, the transistors are sc1815 I think, and you can get a bunch of them online for a couple bucks. I spent a few bucks and got 20. At the parts store they charged me 2 bucks for just 2. Anyways, I put those two in and switched the others around and that noise you described is gone. Try that
 
Should be noted that I wasted time first by replacing the caps on the audio board of the PCB. This did not solve the issue. Swapping out the transistors DID. :)
 
Should be noted that I wasted time first by replacing the caps on the audio board of the PCB. This did not solve the issue. Swapping out the transistors DID. :)

where is Q4 located?

I put the board it two diff donkey kong machines and it had the same issue.
so im pretty sure its not the monitor
 
Do you have the 2 board or 4 board? Q4 on the 2 board is on the CPU board, about 3 inches below the dip switches. On the 2 board, tr4(I'm unsure if this is the exact equivalent of q4) is on the lower left corner of the sound board. C1815 transistors, nte equivelent nte 85 I believe.
 
I'm having this exact issue. (At least I believe I am)

Here is my thread: http://forums.arcade-museum.com/showthread.php?t=364831

Here is the video of the sound mine is making: https://www.youtube.com/watch?v=vl1bEBO3RjM

Here is everything I've done so far and it has still not fixed the issue:

1. Capped the monitor
2. Replaced the audio amp with a repo from twisty wrist
3. New audio caps on the audio portion of the CPU board
3. All new transistors on the audio portion of the CPU board (including Q4 and Q6)

The only thing left (and I'm currently doing now) is capping the power supply itself.

However, I think capping the PS will only help the buzz sound. As far as the "siren" sound (or constant jumping sound) is somewhere on the audio portion of the CPU board.

I'm really dying to know exactly what this issue is as well.

EDIT: According to Mike's Arcade repair log:

Problem: Whirring sound all the time.

Sounds like the jump sound never completely cuts off.

Solution: replace transistor Q4 on the CPU board, a 2SC 1815

https://www.mikesarcade.com/arcade/repairs/dkong.html (scroll about 1/2 way down)

I already tried this and it didn't fix my issue, but I might try it again.
 
Last edited:
Do you have the 2 board or 4 board? Q4 on the 2 board is on the CPU board, about 3 inches below the dip switches. On the 2 board, tr4(I'm unsure if this is the exact equivalent of q4) is on the lower left corner of the sound board. C1815 transistors, nte equivelent nte 85 I believe.

Yeah i have both, a couple 2 board sets and 1 - 4 board set.
Imma go get those NTE ones tomorrow and change out Q4 see what happens.
 
I'm having this exact issue. (At least I believe I am)

Here is my thread: http://forums.arcade-museum.com/showthread.php?t=364831

Here is the video of the sound mine is making: https://www.youtube.com/watch?v=vl1bEBO3RjM

Here is everything I've done so far and it has still not fixed the issue:

1. Capped the monitor
2. Replaced the audio amp with a repo from twisty wrist
3. New audio caps on the audio portion of the CPU board
3. All new transistors on the audio portion of the CPU board (including Q4 and Q6)

The only thing left (and I'm currently doing now) is capping the power supply itself.

However, I think capping the PS will only help the buzz sound. As far as the "siren" sound (or constant jumping sound) is somewhere on the audio portion of the CPU board.

I'm really dying to know exactly what this issue is as well.

EDIT: According to Mike's Arcade repair log:

Problem: Whirring sound all the time.

Sounds like the jump sound never completely cuts off.

Solution: replace transistor Q4 on the CPU board, a 2SC 1815

https://www.mikesarcade.com/arcade/repairs/dkong.html (scroll about 1/2 way down)

I already tried this and it didn't fix my issue, but I might try it again.


Ok heres what i did..

New Diodes, Flyback, caps, filter cap, vert transistors,
Rebuilt sound amp, New pots.

CPU Board has caps replaced already.
 
I'm having this exact issue. (At least I believe I am)

Here is my thread: http://forums.arcade-museum.com/showthread.php?t=364831

Here is the video of the sound mine is making: https://www.youtube.com/watch?v=vl1bEBO3RjM

Here is everything I've done so far and it has still not fixed the issue:

1. Capped the monitor
2. Replaced the audio amp with a repo from twisty wrist
3. New audio caps on the audio portion of the CPU board
3. All new transistors on the audio portion of the CPU board (including Q4 and Q6)

The only thing left (and I'm currently doing now) is capping the power supply itself.

However, I think capping the PS will only help the buzz sound. As far as the "siren" sound (or constant jumping sound) is somewhere on the audio portion of the CPU board.

I'm really dying to know exactly what this issue is as well.

EDIT: According to Mike's Arcade repair log:

Problem: Whirring sound all the time.

Sounds like the jump sound never completely cuts off.

Solution: replace transistor Q4 on the CPU board, a 2SC 1815

https://www.mikesarcade.com/arcade/repairs/dkong.html (scroll about 1/2 way down)

I already tried this and it didn't fix my issue, but I might try it again.


Also, i believe if you "JUMP" sound is effected , its more than just the Q4.

I still have all my sounds including a nice clean jump sound.
 
Also, i believe if you "JUMP" sound is effected , its more than just the Q4.

I still have all my sounds including a nice clean jump sound.

Interesting. Good to know.

Mine plays fine, no graphic glitches and all sounds are clean. (the jump sound doesn't sound warped in any way) I just have a constant hum in the background and that siren sound in the background.

Also, when you initially turn on your DK, it should normally make a "boing" sound. Well, mine tries but it gets cut off and only plays the 2nd half of that noise.

I've got a glitchy DKjr that I'm going to throw in the cab. That will narrow the problem down pretty quick.

Sorry, didn't want to derail your thread. Just excited to see that I'm not totally alone! Between the 2 of us, I'm hoping we can narrow this down.
 
sounds like your missing your music and some sound effects too. I had this happen and I swapped out my 8035 mpu chip and this solved it. Your whirring sound is exactly what mine sounded like and replacing the transistors fixed mine

Interesting. Good to know.

Mine plays fine, no graphic glitches and all sounds are clean. (the jump sound doesn't sound warped in any way) I just have a constant hum in the background and that siren sound in the background.

Also, when you initially turn on your DK, it should normally make a "boing" sound. Well, mine tries but it gets cut off and only plays the 2nd half of that noise.

I've got a glitchy DKjr that I'm going to throw in the cab. That will narrow the problem down pretty quick.

Sorry, didn't want to derail your thread. Just excited to see that I'm not totally alone! Between the 2 of us, I'm hoping we can narrow this down.
 
Interesting. Good to know.

Mine plays fine, no graphic glitches and all sounds are clean. (the jump sound doesn't sound warped in any way) I just have a constant hum in the background and that siren sound in the background.

Also, when you initially turn on your DK, it should normally make a "boing" sound. Well, mine tries but it gets cut off and only plays the 2nd half of that noise.

I've got a glitchy DKjr that I'm going to throw in the cab. That will narrow the problem down pretty quick.

Sorry, didn't want to derail your thread. Just excited to see that I'm not totally alone! Between the 2 of us, I'm hoping we can narrow this down.


Welp , you are alone again lol.. those transistors fixed my problem.
 
You need to check balance pot on the cpu board...Must be turned all the way to one side since sounds are missing....
I'm having this exact issue. (At least I believe I am)

Here is my thread: http://forums.arcade-museum.com/showthread.php?t=364831

Here is the video of the sound mine is making: https://www.youtube.com/watch?v=vl1bEBO3RjM

Here is everything I've done so far and it has still not fixed the issue:

1. Capped the monitor
2. Replaced the audio amp with a repo from twisty wrist
3. New audio caps on the audio portion of the CPU board
3. All new transistors on the audio portion of the CPU board (including Q4 and Q6)

The only thing left (and I'm currently doing now) is capping the power supply itself.

However, I think capping the PS will only help the buzz sound. As far as the "siren" sound (or constant jumping sound) is somewhere on the audio portion of the CPU board.

I'm really dying to know exactly what this issue is as well.

EDIT: According to Mike's Arcade repair log:

Problem: Whirring sound all the time.

Sounds like the jump sound never completely cuts off.

Solution: replace transistor Q4 on the CPU board, a 2SC 1815

https://www.mikesarcade.com/arcade/repairs/dkong.html (scroll about 1/2 way down)

I already tried this and it didn't fix my issue, but I might try it again.
 
Nice VertexGuy! Glad you fixed your issue. I might try the transistors again. I need to finish cappng my power supply first though.

You need to check balance pot on the cpu board...Must be turned all the way to one side since sounds are missing....

Sorry, where is the "balance pot"?

(And just to be clear, I don't have sounds missing while the game is playing. The only sound that gets cut off is the initial "boing" sound the game makes when you turn it on.)
 
I thought that was kind of funny, especially with the username.
Not being critical, just sharing my joy.

That's funny. I didn't realize the misspelling, and now I see the irony. As for the music missing, I was going by the video provided, and their were sounds missing ;)
 
As for the music missing, I was going by the video provided, and their were sounds missing ;)

Aw crap...sorry! That was an old video. I've since fixed the "lack of sounds" issue. I can now hear intro music, coin inserts, game music, DK stomping, jump sounds, etc.

Here is a more recent video of my sound problems. Background buzz and that background siren:

https://www.youtube.com/watch?v=dPQKSIgcQfY
 
Noticed my DK Jr is starting to have a similar problem. Sounds like a portion of the jump sound is looping, but it is very faint at this point, you really only notice it if the sound is cranked. Hasn't been bad enough for me to fix, but if it gets worse its good to know there are a few things I can try
 
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