WG K4900 AC Voltage?

TCinTEXAS

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I've found lots of opinions, but no clear answers on this:

My Moon Patrol AC voltage from the isolation transformer to the WG K4900 is 130vac. Is this too high? If so, what should I do about it?
 
check the iso output rating listed on it and if its within +-10% it should be good, BUT 130vac does seem alittle high. i personally would switch it out just to be safe but i am overly cautious.
 
was this measured with the monitor unattached? If so, its totally invalid and means nothing. You must test the voltage under load. It will likely be spot on 120VAC.
 
was this measured with the monitor unattached? If so, its totally invalid and means nothing. You must test the voltage under load. It will likely be spot on 120VAC.

I tested it at the power connector with the monitor disconnected, then at the transformer terminals with the monitor connected. No change.

EDIT: By the way, the monitor has no neck glow, so it may not be drawing a load when attached.
 
yeah, that isn't any load. Check fuses, etc......

The fuse on the 4900 chassis was blown (4a, I don't remember the number.). I replaced it. The fuse on the AC source is good, and the 5(?) fuses on the P/S board all tested ok, not that they would have anything to do with the monitor. Is there another one I'm missing?
 
UPDATE:

I think I found part of the problem. I removed the chassis and found several jumpers, including a jumper bypassing the 4A fuse. There are a couple of others. Does anyone know what they are? Are they useful? Should I remove them?

Chassis top:
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Chassis bottom
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The only jumper that is factory is the black wire. The blue wire may be there to repair a broken trace. But is not factory. First thing to do is get rid of the fuse holder and the white jumper bypassing the fuse. Get a 4 amp pigtail fuse and install it in the chassis where the fuse goes.

Here is a link to a flowchart to follow before powering the chassis up; http://antelopearcade.com/files/Monitor Manuals/FLOWCHART_-_WELLS_GARDNER_K4900_(U).pdf
 
The only jumper that is factory is the black wire. The blue wire may be there to repair a broken trace. But is not factory. First thing to do is get rid of the fuse holder and the white jumper bypassing the fuse. Get a 4 amp pigtail fuse and install it in the chassis where the fuse goes.

Here is a link to a flowchart to follow before powering the chassis up; http://antelopearcade.com/files/Monitor Manuals/FLOWCHART_-_WELLS_GARDNER_K4900_(U).pdf

Will do. Just so I'm understanding, what's wrong with a fuse in a fuse holder?
 
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Ok. Another question or two:

What's the part number and/or where do I get a Horizontal Width Coil for the WG K4900?

I'm doing the cap kit. It's going well. Inspecting the board, and noticed the HOT is shorted. Got one ordered. I also noticed that the Horizontal Size Coil is snapped off just below the windings. I've searched, but I can't find a part or model number for this. It has 0098 (or possible 8600, if I'm reading it upside down) stamped on the top.

In doing the cap kit, capacitor C366 doesn't have a capacitor to replace. There's a spot for it on the board, but no cap. On the bottom of the board, the hole is plugged with solder (looks original). I'm assuming I just leave that one out, right?
 
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Ok. Another question or two:

What's the part number and/or where do I get a Horizontal Width Coil for the WG K4900?

I'm doing the cap kit. It's going well. Inspecting the board, and noticed the HOT is shorted. Got one ordered. I also noticed that the Horizontal Size Coil is snapped off just below the windings. I've searched, but I can't find a part or model number for this. It has 0098 (or possible 8600, if I'm reading it upside down) stamped on the top.

In doing the cap kit, capacitor C366 doesn't have a capacitor to replace. There's a spot for it on the board, but no cap. On the bottom of the board, the hole is plugged with solder (looks original). I'm assuming I just leave that one out, right?

correct C366 if it doesn't originally have a cap then don't install it.
 
Ok, back to this guy again. I recapped the original MP K4900 chassis, and replaced the HOT. Still no neck glow. The P70 connector looks a little burned. Pins look good. Haven't checked continuity back to the main board yet.

So. No neck glow. Where should I start?
 
Ok, back to this guy again. I recapped the original MP K4900 chassis, and replaced the HOT. Still no neck glow. The P70 connector looks a little burned. Pins look good. Haven't checked continuity back to the main board yet.

So. No neck glow. Where should I start?

first thing is to check B+ and see what its at.
 
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