New Donkey Kong Jr - Few issues

Constellation

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Hello! I know very little about arcades! I am learning a TON from my Asteroids project, but still not nearly qualified to even begin on many projects! With that said - I bought another project..... a Donkey Kong Junior.

This machine is essentially working. The image on the monitor has a lot of lines through it, but I can see it showing the gameplay. I can see the text that says insert coin, and it shows through the demo to entice players.

However, there are a few issues and with me being so new to this, I thought I would turn here for some help.

For starters, there is no sound. After some reading, I think there is a sound board/amp/something-rather. I haven't checked the caps on it, but if I recall, I believe there is some sort of an LED on there, and I don't recall seeing mine have an LED light up - if there was even one there.

The monitor - as I said - produces an image that is very hard to see. I am probably going to start with a cap kit on this and see what it produces. Who sells cap kits for DKJR? If this doesn't clean up the monitor (I'll post pics when I get home of what it does), any recommendations?

Lastly - it doesn't appear that the coin door is working properly. It doesn't register that a coin has been inserted. I checked the coin pin-outs on the board, and they're getting 5v, but I can put a coin in both slots, and the text still says "insert coin" - any ideas as to what to do here?

I'll attach a few pics! I paid $200 for the machine and am very very happy with it!

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First figure out which monitor you have, likely a 20EZ. Arcadeshop.com has cap kits for these and the sound board, they even have drop in replacements for the sound board. The monitor is COMPLEX to remove the chassis to work on. Look for YouTube video on removal...I think someone on KLOV posted a link to their video on YouTube. The sound board can be swapped out, or removed and recapped, without near as much trouble. Do some reading up on the monitor as there is a lot of good info out there. I have not recapped mine yet but have swapped audio board with a drop in replacement. Mine looks pretty good but I dread the day...
 
Do not buy caps from arcadeshop they're pictures show xicon caps and those are extremely low quality for the price. 5 more bucks and you get a kit that lasts you a lifetime from security001 and yes I do think a kit will fix this as I fixed someones monitor with same issue using a cap kit. You need to adjust it and cap it. The audio amp could be bad or something like the sound cpu could be off not sure cap the thing they come with security's kits anyways.
 
Do not buy caps from arcadeshop they're pictures show xicon caps and those are extremely low quality for the price. 5 more bucks and you get a kit that lasts you a lifetime from security001 and yes I do think a kit will fix this as I fixed someones monitor with same issue using a cap kit. You need to adjust it and cap it. The audio amp could be bad or something like the sound cpu could be off not sure cap the thing they come with security's kits anyways.

So the wire coming to the speaker isn't getting any voltage - so I am going to assume that the audio amp definitely needs a cap kit. As well as the monitor.....

Any ideas as to why the coin mechs aren't working properly? The board is showing 5v, and I measured AT the mech, and also get 5v...so I don't understand why it doesn't register a quarter.

It also appears that a wire for the test switch has been cut.
 
So the wire coming to the speaker isn't getting any voltage - so I am going to assume that the audio amp definitely needs a cap kit. As well as the monitor.....

Any ideas as to why the coin mechs aren't working properly? The board is showing 5v, and I measured AT the mech, and also get 5v...so I don't understand why it doesn't register a quarter.

It also appears that a wire for the test switch has been cut.

Tbh I dont know much about mechs as I never use them I bypass them anyway possible ;)
I think its connector p3 on the pcb if it's using little connectors rather than edge connector setup but anyways the board should be labeled coin and and there should be a 3 position connector. see if anything is connected to it.
 
Tbh I dont know much about mechs as I never use them I bypass them anyway possible ;)
I think its connector p3 on the pcb if it's using little connectors rather than edge connector setup but anyways the board should be labeled coin and and there should be a 3 position connector. see if anything is connected to it.

Yeah its connected, and putting out the correct voltages!
 
So the wire coming to the speaker isn't getting any voltage - so I am going to assume that the audio amp definitely needs a cap kit. As well as the monitor.....

Any ideas as to why the coin mechs aren't working properly? The board is showing 5v, and I measured AT the mech, and also get 5v...so I don't understand why it doesn't register a quarter.

It also appears that a wire for the test switch has been cut.

I wouldn't replace the sound amp I would fix it. Have you adjusted the volume pot by the sound amp to make sure it's not just turned down? Have you checked continuity of the wires running from the PCB to the amp and the amp to the speaker?

As for the mechs, try removing the two wires and touching "shorting" them together to see if you get a credit. If so then you just likely have a mechanical issue with your mech. If not and the wires have continuity to the board then I would suspect its a PCB issue. And like Mike said, check the test switch. I didn't know that one!
 
I wouldn't replace the sound amp I would fix it. Have you adjusted the volume pot by the sound amp to make sure it's not just turned down? Have you checked continuity of the wires running from the PCB to the amp and the amp to the speaker?

As for the mechs, try removing the two wires and touching "shorting" them together to see if you get a credit. If so then you just likely have a mechanical issue with your mech. If not and the wires have continuity to the board then I would suspect its a PCB issue. And like Mike said, check the test switch. I didn't know that one!



I have checked the volume pot, and I turned it all the way up. The speaker line has 0v, I haven't tested if the voltages are getting to the board yet. There is one wire cut on the test switch, so let me wire it back up this evening and see if that does anything.
 
As for the monitor, have you tried simple stuff like adjusting the screen knob on the flyback, and brightness on the remote board (next to the volume pot)? There is also a sub-brightness on the main video chassis board, which can be a bit tricky to get to. (3) things that can affect brightness, and based on your description (pics would be more helpful), might just be some simple adjusments to get you back in business with the monitor. Those would be good to start with, to see if you can get the image better and then start fine-tuning brightness and colors from there.

Arcade Buffett has a good Sanyo 20EZ chassis removal video on youtube, if you end up needing to go that route:

https://www.youtube.com/watch?v=1cIMzB7kLeY
 
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As for the monitor, have you tried simple stuff like adjusting the screen knob on the flyback, and brightness on the remote board (next to the volume pot)? There is also a sub-brightness on the main video chassis board, which can be a bit tricky to get to. (3) things that can affect brightness, and based on your description (pics would be more helpful), might just be some simple adjusments to get you back in business with the monitor. Those would be good to start with, to see if you can get the image better and then start fine-tuning brightness and colors from there.

Arcade Buffett has a good Sanyo 20EZ chassis removal video on youtube, if you end up needing to go that route:

https://www.youtube.com/watch?v=1cIMzB7kLeY

Thanks fro the link! Let me post a video of what my monitor is doing! I have adjusted all the knobs I could find to try and get it to clear up.
 
Here is a video of what my monitor is doing. It's hard to tell, but you can see the screen changing in the background showing the 'demo' mode. It also clears up some after its been on for a few minutes. Ignore my 5 month old complaining about something in the background! :)


https://www.youtube.com/watch?v=erjwXwSPKmM&feature=youtu.be

I guess you can't embed YouTube here?
 
Tried vertical and horizontal hold? That and re-seat all the rom chips on the game boards.

Past that, I defer to the more expert members.
 
Even if you can adjust the horizontal hold to get a picture... it's pretty apparent you're going to need to re-cap that monitor.
 
I have connected the wire on the test switch. No in the chaos of the screen, every so often a "push" button shows up. If you push Player 1, its like the game starts briefly, showing Donkey Kong going up the elevator, but then changes screens again to show high scores.
 
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