NEED TO GET INTO SERVICE MENU AND KNOW WHAT ABBREVIATIONS OR FOR

Do you have the remote? After looking at the manual which you can download here:
http://www.retrevo.com/support/Zenith-H20F50DT-TVs-manual/id/277ci168/t/2/
it seems all that is needed is to hit the menu button.

hi
there is 3 possible cause
1=bad solder
2=defective capacitor
3= defective jungle ic (control pix functions)

Thank you for your quickly response.
Yes, is repairable your tv.
Need be replace STK 392-120 IC , two pieces. Plus possilbles resistors (burn), prices is variable , depend where are you located and depend labor on each shop. but, is around $285--$400.
Because after replace STK IC's, your tv need a lot work on service menu area ( is no customer menu setting, this is special section on eprom service menu.
I hope my information is good for you.
Appreciate any opinion from you
Thank you

To access the Zenith service menu: Hold down the menu button on the remote control until the menu disappears. Then type in 9-8-7-6-enter. This should do the trick. Be careful what setting you change. I would recommend writing them down before you change any. Hope this helps.

Hi,

You need to use the original LG RT52SZ60DB remote.

1. Press MENU buttons on the REMOTE and on the TV at exactly the same time and hold for about 3 seconds (TV buttons are just below lower left of screen)
2. Scroll down the SERVICE MENU to No. 14 LAMP REPLACE
3. Press VOL |> button to enter lamp hours
4. Press OK button to RESET hours, or CANCEL/EXIT to Exit menu

Hope this helps.

Cheerz ;^)

You need to go into the service menu and turn the ac power setting to off and read to see if you can get the channel to scan To enter service menu: hold down menu on remote until menu disapperar then type in 9-8-7-6 then enter. Continue as described

significant vertical overscan. It is such that it's impossible to read crawls and such at the bottom of the screen. I think this problem is a tv problem. it is due to vertical section. please change electrolytic capacitor in vertical output section. it will be ok. it is common problem can be fixed at home & very simple.

service menu code is 9876, i think. and you can manually adjust the focus using network54's post on "blurry z27x22d".

Does not seem like a bad tube alone. Could also be that the Video output Transistors Supply Filter capacitor having dried out. It is a 100mfd 160V capacitor, which on replacement will improve the brightness of the immage. And yes, you could also try increasing the heater voltage (Filament Voltage)of the Pictuire tube, this will definitely increase brightness, but will reduce the life of the Picture tube. You gotta think - 10 year old TV, should I repair or exchange and get a new one???

Done!