Just Re-capped a DK Jr. Monitor...question...

sk8ersublime

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Hi,

I just recapped a DK jr monitor that my cousin gave me. I finished the job, everything went really smooth. Here is my question.

I plugged it directly into the wall, no game attached, will it turn on? It did not power up. I am wondering if I did something wrong. I do not have a PCB board to test it with right now, but I was hoping to atleast hear it power up or give me light.

Any suggestions or ideas?

Thanks,
Chad
 
Hi,

I just recapped a DK jr monitor that my cousin gave me. I finished the job, everything went really smooth. Here is my question.

I plugged it directly into the wall, no game attached, will it turn on? It did not power up. I am wondering if I did something wrong. I do not have a PCB board to test it with right now, but I was hoping to atleast hear it power up or give me light.

Any suggestions or ideas?

Thanks,
Chad

OH NOES!!! DON'T DO THAT!! The monitor is a 100V monitor. Your wall is 120V.

Plug it into the outlet on the bottom of the cabinet. That is a 100V outlet.

Check the fuses, you might have nuked them or worse yet, your monitor's board! D'oh!!!!!!
 
From what I understand you should not plug a monitor directly into a wall socket!!!

This is true if the monitor requires an Isolated Transformer (which the 20EZ does). My newer Wells does not and is plugged into an outlet.
 
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I didnt hear any pop either....oh man, now im worried...lol...the monitor was already discharged, now i cant mess with it because i dont have a discharge tool...i guess ill be going to radioshack.
 
I didnt hear any pop either....oh man, now im worried...lol...the monitor was already discharged, now i cant mess with it because i dont have a discharge tool...i guess ill be going to radioshack.

Discharge tool = long screwdriver, electrical tape and some wire.
 
Discharge tool = long screwdriver, electrical tape and some wire.

lol yea...

I checked the fuses, they seem to be fine, but does it seem normal that the monitor will not fire up with out it being on a switch in a cab? I would think it would just turn on regardless if a game is hooked up.
 
Found this in Ian's post:

DON'T connect a monitor directly to a wall socket! Most game monitors are "hot chassis", and as such require an isolation transformer. Plugging such a monitor directly into a household wall socket will fry stuff. This especially includes Nintendo monitors. They have a standard looking wall plug on the cord, but that's meant only for the 100v isolated socket in the bottom of the game.

Sorry dude- hope it's not that big of a deal...
 
Arcade monitors are hot chassis, and therefore REQUIRE an isolation transformer. Plugging one directly into the wall will destroy several parts in the power supply. There should have been a pop or some smoke, but maybe not. You've more than likely fried at least a couple of the rectifier diodes and blown the fuse - check those parts first.

ONLY plug the arcade monitor into the oultet in the cabinet, never directly into the wall!!! The Nintendo monitors look like they have a normal plug on the end - but this really needs to be connected to the isolated 100v AC power source in the game. The extra voltage (120v versus the 100v) isn't the main issue - the monitor will actually operate like that for a while without destroying itself. The issue is that you've plugged a hot chassis monitor in without the isolation transformer, effectively shorting out the monitor's power supply.

Chances are, when you plug the monitor back into the game, it'll be dead - the main fuse is blown. Put in a new fuse, and watch that one blow too. Time to start replacing blown power supply components. Start with the rectifiers, the move on to the current limiter transistor in the B+ supply. Also check the large ceramic resistor.

-Ian
 
How to make your own discharge tool:
http://www.therealbobroberts.net/sb.html

grinding drilling connector meh thats to much work lol

heres my hndy dandy discharge tool its been used for over 100 monitors and works like a champ

all i did was strip about 1 1/2 inches of wire and wrap it around the screwdrive a few times zap a little solder on it to hold it in place then wrap that in elect tape

and at the time i was a little parnoid so i wraped the handle of the driver as well in elect tape lol

HPIM0447.jpg
 
lol yea...

I checked the fuses, they seem to be fine, but does it seem normal that the monitor will not fire up with out it being on a switch in a cab? I would think it would just turn on regardless if a game is hooked up.

Check the main fuse again (larger one) with a multimeter, sometimes they can blow without being visually obvious.

The monitor IS supposed to come on when simply connected to power. With no video input, you should get a white or grey screen (Nintendo monitors use inverted video signals). Non Nintendo monitors will come on with a black screen - but you can turn the SCREEN control up to get retrace lines and a light raster.

Plug the monitor into the socket in the cabinet, and power it up. If you're getting nothing, and you hear no high voltage, start checking voltages in the monitor - starting with the B+. The B+ supply test point is labelled BJ on the board. Put the black lead from your meter on the monitor's metal frame, and the red lead on the BJ test point. You want it to be 108v DC. If it's really high, like 145v, then the monitor is in HV shutdown mode. If it's zero, then you have something really wrong with the power supply. Check for AC at the input, and right after the fuse.

-Ian
 
Arcade monitors are hot chassis, and therefore REQUIRE an isolation transformer. Plugging one directly into the wall will destroy several parts in the power supply. There should have been a pop or some smoke, but maybe not. You've more than likely fried at least a couple of the rectifier diodes and blown the fuse - check those parts first.

ONLY plug the arcade monitor into the oultet in the cabinet, never directly into the wall!!! The Nintendo monitors look like they have a normal plug on the end - but this really needs to be connected to the isolated 100v AC power source in the game. The extra voltage (120v versus the 100v) isn't the main issue - the monitor will actually operate like that for a while without destroying itself. The issue is that you've plugged a hot chassis monitor in without the isolation transformer, effectively shorting out the monitor's power supply.

Chances are, when you plug the monitor back into the game, it'll be dead - the main fuse is blown. Put in a new fuse, and watch that one blow too. Time to start replacing blown power supply components. Start with the rectifiers, the move on to the current limiter transistor in the B+ supply. Also check the large ceramic resistor.

-Ian

I just took the board out again...nothing looks/smells burned, no fuses are blown. I really think there is another issue...i guess i need to get that isolation transformer to test...ill take the monitor back this weekend to the cab.
 
How to make your own discharge tool:
http://www.therealbobroberts.net/sb.html

That's a very nice way to make a discharge tool, but it's way overkill. I just take a cleaplead and attach one end to a screwdriver shaft, and the other end to the monitor's frame. No need to make up a permanent tool, but you can if you want to. I used to have a screwdriver like that with a wire attached to it (only I just wrapped the wire a couple times and taped it) - it was too much of a pain to have getting tangled up in the toolbox for how little time it saved. Easier just to use a regular clip lead when I needed it.

-Ian
 
Thanks guys, I will check it out this weekend then I guess. I dont see how i screwed anything up during the re-cap, it was rather simple. (ive never done this before if you havent noticed yet lol...) I wanted to use this monitor with an ArcadeVGA for my scratch built DK cabinet.

I usually post of BYOAC...i dont know the feeling here for repos and mame....

Here is my DK cab thread I had over there if anyone is interested.

http://forum.arcadecontrols.com/index.php?topic=100572.0;all
 
lol yea...

I checked the fuses, they seem to be fine, but does it seem normal that the monitor will not fire up with out it being on a switch in a cab? I would think it would just turn on regardless if a game is hooked up.

A monitor by itself will power up without a game attached, but you might not see anything on the screen if the brightness is properly set. You should see the heater element in the tube's neck glow, and if you adjust the brightness all the way up, you should see a raster pattern on the monitor.

An isolation transformer is not required for a monitor plugged in by itself (without a game), simply to see if it works. However, risk of shock is increased, and you should never use a monitor without an isolation transformer with a game or with any test equipment!
 
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