JVC Mod AV27820 screen trouble

psychojim40 · Joined: 12 Sep 2005 Posts: 13

Hi every one, I've a trouble with my JVC AV27820. When I put at ON, the both top corner still black but the screen appeared. After 10 second, it shuting of by itself and the power light blink. The deflection seem to be ok ( I,ve seen there continuity in the wire) I really don't know what's going on !!!! Any help or service manual about this product will be really appreciated. I've already the first 6 page of the service manual on 23 and not able to find it!!!!

edolago

edolago · Posted: Sat Jun 17, 2006 5:37 pm Post subject:

Is it a KEYSTONE? If it is, Check again your deflection yoke. That trouble is an open upper horizontal yoke winding. If you check the continuity, you can not determine the open upper winding because it is connected in parallel with the lower horizontal winding. Mostly it is a corroded terminal that causes it to open. Rolling Eyes

edolago · Posted: Sat Jun 17, 2006 5:45 pm Post subject:

Or, maybe the yoke itself is defective. It has some shorted wiring of the upper horizontal winding. You can pull out the yoke from the tube and check if some windings are corruded or shorted. Rolling Eyes

psychojim40 · Joined: 12 Sep 2005 Posts: 13

I find all the bugs !!
Replace D422 (1N4761A,NTE5064A),C425 (100uf/35V),C425 (470uf/35)R526 1,8 Ohms Termal resistor IC421 (Vert.Deflec) and went to service menu to unlock channel and sound with the orinal remote control by pressing 2 button at same time (menu/mute)