Blowing fuses after "dusting"

Evil Reny

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I picked up this NBA JAM thats non working the guy I got it from said it was working great until he went and "dusted" the back of the monitor. Now it keeps blowing the fuse thats in line with the 120 volt feeding the monitor.

I haven't looked at it yet I just unloaded it last night but want to take a look today.

Any suggestions at where to start?

BTW what value should this fuse be?
 

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Is this a K7000A? I see the double wire to the anode cup. Make sure during his "dusting" that he didn't disconnect the DAG wire...
 
There is a black wire from the tube to the neck. if it comes unconnected, you gets multiple sparks from the chassis to the tube/frame. After a little bit, the VR can blow, causing the fuse to blow.

Not saying this happened, but it might have...
 
O.K I tested and found that D20 and D21 are shorted. After reviewing the manual it says that these "should be replaced with exact factory replacement parts" Is this really necessary?

Parts list calls for "Diode SI 1A 600v" for both

Or can I find this at an electronics store?
 
As long as they are 1A 600v, it'll work. Or you can pull the part, look at the number on the diode, and and then find the NTE cross reference...
 
Replaced the two diodes and she fired right up.

Need to degauss a bit but looks good.

Thanks for the help Mod. :)
 

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AHHH!!!!! I missed a good chance to say "check the diodes in the bridge" !!!... and it would've been right this time... dangit.
 
I rarely seen those diodes go out unless someone hook that monitor up without a isolation transformer. Was that monitor always in there? If not, then other parts might have become weaken from that and will go out after awhile. Also sitting in certain areas dust and other build up on the tube can cause arcing to go from the anode down the tube til the ground strap or something else shunts it to ground.
 
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