New Donkey Kong Jr - Few issues

mine did the EXACT same thing , H-HOLD was toast, TR901 was toast and the HOT .
order a kit from security or buffet would be your best bet, looks like it needs one anyway, if you ask security can put a "delux" kit together with B+ and H-HOLD pots.

http://forums.arcade-museum.com/showthread.php?t=366148
pic of mine doing that in this thread.
have you tested your B+ yet? report back what you get ( VDC setting) i chased my issues around forever! non adjustable B+ ( super high in the 130VDC) big resistors getting hot like crazy and going HV shutdown) , i only found my HV issue by accident when i was testing the B+ , shut the machine off and still had my DMM connected and on and touch a lead to the chassis by accident and saw my B+ was shorted to ground. HOT was shorted , took out tr901 and i am guessing the h-hold at the same time.


Thank you for this! I have not checked the B+

I will hvae to find that on the schematics and test it. I'll report back this evening!
 
No worries! My youtube video comments say the sync issue was caused by B+ not being at the proper voltage.

It was under 108V, and when I tried to increase the B+ POT even a tiny bit it would go into HV shutdown. I performed a much needed cap kit and then I was able to adjust B+ to 108V.

It even mentions this on the flowchart. The chart is essential for things like this:

https://www.flickr.com/photos/justbriand/7719747128
 
VR601 adjusts B+, as shown on the schematic. R609 is right next to it. R609 is a white thing that sticks up off the board, with a couple long legs that are easy to clamp to, to measure B+. You want to clamp the positive lead from your multimeter or voltmeter to the leg that is closest to the monitor. Clamp your negative lead to any metal part of the cabinet. The monitor frame is the easiest to clamp to.

You are best to use a non-conductive screw driver to adjust B+. Bob Roberts sells a plastic tool kit with 4 or 5 tools in it, one of which will work to adjust VR601. HOWEVER, in my case at least, after 3 or 4 uses, the ends of the tools deformed to the point that they no longer turned it. I have a small screwdriver with a plastic and rubber handle, and the smallest flat head bit works perfectly for these VR's. The bits are the only metal part on the screwdriver. Will try to get a picture of the set, and a make and part number, in case that info would be useful to anyone. You don't want to go sticking anything with long metal parts into your chassis. You also want to be extremely careful reaching around in there with the monitor on. Alternatively, you can adjust with power off, and turn it on to check, then power off and adjust, rinse and repeat. But, that can be time consuming.

Anyway, once you have multimeter/voltmeter hooked up, and set to the 200 VDC range, check B+. If it is not at 108V, adjust VR601 veeeerrrrry slowly in either direction to adjust accordingly.
 
see TP91?? beside that is BJ that pin is the B+ TEST POINT. alternatively as noaffinity stated you can also use the leg of R609 , close to the bj pin also. ( r609 is a large ceramic resistor) ,
also you can use the pink wire going to the audio board ( been a while, i think its the pink, check continuity from bj to the connector going to the audio board from the main chassis . see attachment , upper right area "TP91"
 

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see TP91?? beside that is BJ that pin is the B+ TEST POINT. alternatively as noaffinity stated you can also use the leg of R609 , close to the bj pin also. ( r609 is a large ceramic resistor) ,
also you can use the pink wire going to the audio board ( been a while, i think its the pink, check continuity from bj to the connector going to the audio board from the main chassis . see attachment , upper right area "TP91"


My BJ Test point reads 102.5V
 
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My BJ Test point reads 102.5V - so what does that mean?

Your volts are low. The volts should be at 108-110 usually try to get it as close to 108 as possible. If you can while you recap the chassis replace the b+ pot. Be super careful when adjusting the b+ don't touch the leads on the meter. You won't be able to sync the thing until the chassis is corrected.
 
Your volts are low. The volts should be at 108-110 usually try to get it as close to 108 as possible. If you can while you recap the chassis replace the b+ pot. Be super careful when adjusting the b+ don't touch the leads on the meter. You won't be able to sync the thing until the chassis is corrected.

Am I better off NOT adjusting anything now until after I do the cap kit?
 
It shouldn't hurt to adjust it now, and it may improve things, but likely not, as it's not too far off of nominal. But, yes, go ahead and adjust, get it to 108V or as close as possible, and see if things improve.

AND be prepared to adjust again after any work on the chassis.

BTW, here is the screwdriver set that I use to adjust VR's. There is no identifying information on the set. The bits are stamped "china" and then what appears to be some sort of size information. The flatheads are 'china 2', 'china 3' and 'china 4'. The smallest ('2') is the one I use for the VR's. I'm guessing that translates to 2mm.



 
It shouldn't hurt to adjust it now, and it may improve things, but likely not, as it's not too far off of nominal. But, yes, go ahead and adjust, get it to 108V or as close as possible, and see if things improve.

AND be prepared to adjust again after any work on the chassis.

BTW, here is the screwdriver set that I use to adjust VR's. There is no identifying information on the set. The bits are stamped "china" and then what appears to be some sort of size information. The flatheads are 'china 2', 'china 3' and 'china 4'. The smallest ('2') is the one I use for the VR's. I'm guessing that translates to 2mm.




I have some very similar. Just went to work on it. I can get it up to 107.8v, but if I turn it even slightly more, the monitor tends to shut off.....


Well, even now at 107.8 it just shut off.....
 
I have some very similar. Just went to work on it. I can get it up to 107.8v, but if I turn it even slightly more, the monitor tends to shut off.....


Well, even now at 107.8 it just shut off.....

Hmm very strange shutting off at 107.8 isn't good. You gotta turn your screen brightness down on the flyback see if that helps anything. Otherwise idk.
 
Hmm very strange shutting off at 107.8 isn't good. You gotta turn your screen brightness down on the flyback see if that helps anything. Otherwise idk.

The brightness was cranked to the max. I turned it back some....it ran about a minute and shut off.

Furthermore - when the monitor turns off, the marquee light comes on.....
 
I am sorry, what is "sync?"

Sync is like when the image isn't going ape shit. When the image is stable and sitting there holding that's the sync. Hard to explain but that's the best I can explain because I'm so tired.
 
Sync is like when the image isn't going ape shit. When the image is stable and sitting there holding that's the sync. Hard to explain but that's the best I can explain because I'm so tired.

Ha that actually makes sense. Unfortunately, the image is doing exactly as before.

Also my voltmeter is about the cheapest one you can buy from Home Depot!
 
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