Toshiba tn61x81 picture problem

[stlouis27]

I have a Toshiba rear projection tn61x81 cinema series tv. I only have a picture in the middle of the tv. The bottom 1/3rd is black and the top 1/3rd is black. Any ideas on how to fix this problem?

[RON_CET]

Re: Toshiba tn61x81 picture problem

can you take couple pictures of your problem and upload here?Is this set HDTV? What is the signal source being used? Sounds like from your description your viewing your programming in letter box settings.

[stlouis27]

Re: Toshiba tn61x81 picture problem

Here is a picture of the tv. The set is a HD Cinema series. I'm guessing what you mean by the signal source, that would be cable. No it is not set in letterbox.

[RON_CET]

Re: Toshiba tn61x81 picture problem

that's a vertical deflection problem,I've attached a picture of the vertical ic the photo best i can get because the schematic is very small scale on the original paper service manual.Do you have a digital meter to read voltages at the Q301 vertical?This is a very difficult set to work on do to the board layout and being able to get to the vertical Q301
I need to know what your voltage readings on pins 2,3,6 (pin2)= 19v (pin3)=35v (pin 6)
=35v also due to board age look for possible solder cracks around all pins of Q301 intermittent solder joints could also cause this malfunction as well a defective Q301 vertical ic

[stlouis27]

Re: Toshiba tn61x81 picture problem

Thank you so much. Yes I do have a meter, and I will check this out tomorrow after work and let you know what voltage readings I get.

[stlouis27]

Re: Toshiba tn61x81 picture problem

Can you tell me which board this is on? maybe a location. Having a difficult time locating the vertical output ic. Thanks

[RON_CET]

Re: Toshiba tn61x81 picture problem

Attached from schematic top view of the Deflection board,hard for me remember the chassis layout but I'm thinking the deflection board will be in the center of that chassis it will also be board with board number (PB8920A) marked in black somewhere on the board,also this board will have the HVT (High Voltage Transformer) on this board it's large black device will have maybe 3/4 wires exiting top,If you still have trouble finding take me picture inside top view of back TV and I'll circle the board and repost your image