TV PROBLEM

Good answer.

The number of posters that seek answers on CR4, as opposed to looking in the Original Equipment Manufacturer[OEM]'s Operation and Maintenance Manual or contacting the OEM directly, never ceases to amaze.

Removing and replacing cards "hot" - even me who like to fiddle around with repairs while knowing little haven't tried that yet. I will rather get my adrenaline rush from somewhere else.

Note There are potent voltages inside the box.

I believe by HOTs he meant to say, Horizontal Output Transistors.

Are the horizontal transistors mounted onto a heatsink when they are inside the chassis? If they appear to short when you reinstall them there, the reason might be that you have forgotten to use the thermal washers from the original transistors (you may find they are still stuck to the original transistors with heat sink compound). The case of the HOT's is NOT floating but is usually connected to one of the transistor terminals (e.g. the collector). Without the thermal washer, the transistors can be shorted out and appear to be faulty. Get those washers, apply some new heatsink compound if you have it and reassemble.

Hope this helps

Thanks for this.I actually did what you have described here.What is happening is that when I replace the transistor and test the board without connecting the card to the picture tube,everything seems to be ok,but once the card is fitted to tube,the transistor shorts out upon switching.I am still figuring it out,is there still a problem with components on the board or is the picture tube faulty?

When you remove the card, is the horizontal deflection coil still at the CRT? if you not remove it too, please check it also every component at the card that connected with horizontal deflection coil.

To test CRT, give the filament of CRT about 4,5 - 6 vac, wait until the filament warm, then give 150 vdc to G2 and connect the GND to filament GND, then use volt meter to measure R, G, B pin, if its appear about 75 - 100 vdc from RGB pin, so the CRT is good.

Ok,I will try to remove the horizontal deflection coil and see what happens.I will also test the CRT as described and will bring a feed back.Thanks

Hello again, The Bishop

Please remember not to wear a lurex tie during that procedure.

Kind Regards....