PVM 20m4u Coil Core

Ultrax

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Donor 2017
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I have finally found the cause of the high pitch noise in my 20m4u as a faulty coil core on the main board. Unfortunately, the service manual does not list its specifications and the diagram is very blurry. Also the doing a search for the part number yields no results. Has anyone replaced this and/or know how I can proceed in replacing this part? Thanks.
 

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I think that's the horizontal linearity coil (does the top attract small bits of ferrous metal?). It's not faulty, just not well insulated so the winding resonates at some frequency. It's not uncommon and unless the buzzing sound is making you crazy you'd better leave it alone. If you just can't stand it, remove the external insulation and dip it in insulating varnish (aka coil varnish) minus the legs and let it dry. Then put it back in and hope it stays quiet.
 
The coil was very loose sitting on the board although the solder looked fine. Yes the top is covered in metal, if the varnish doesn't fix the coil where would I find a replacement as it is extremely loud.
 
Linearity coils are the only coils that are magnetically biased. They have a magnet on top and if you put something metallic (not aluminum) near it it will attract it but there shouldn't be any metal on it.

I see there's some white residue on it, probably some silicon to secure it to the PCB or surrounding components. Other than redoing the varnish insulation and resoldering it more securely there isn't much you can do because it's not faulty. If it were you would have serious picture problems. It's a custom part and very critical to the CRT operation, you cannot replace it with a generic part.
 
I will apply the varnish and rtv silicone to secure it to the board. How do I remove the external insulation without damaging the coil, I appreciate all the help as I am rather new to this.
 
small scissors/cutter on the edge, then peel it off with fingernails.
 
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