Need help: Trying to restore a HMV TV with F5 chassis
 

G'day all. Early last year I picked up off the street an ancient HMV (His Master's Voice) B&W TV set dating from 1958-1960ish and am trying to get it restored to working condition with a lot of help from a mate who has had experience back then servicing a lot of those TV sets. Anyways we got it over to his place and he happened to have a book of schematics of old Aussie sets of the 50s and 60s and found the schematic for mine which is a HMV F5 chassis. Anyways the TV has audio and the tube is good, only problem with it is I'm getting a vertical collapse fault, hence a horizontal line across the screen. Anyways found what appears to be the main fault after a bit of testing around the vertical section, the vertical blocking oscillator transformer is buggered. Below are links to couple of webcam shots of the transformer and the circuit diagram of the TV, the vertical blocking oscillator transformer is "T3" on the bottom left side of the diagram in the vertical section. Now there's no ID on the specs of this transformer so I wonder if any of you guys could help identify this transformer and let me know the specifications or let me know of what replacement transformers I can get for this one? Any help would be most appreciated.

Cheers
Troy

http://www.box.net/public/hitr57t1ys (transformer)
http://www.box.net/public/bg5rekbzb3 (transformer)
http://www.box.net/public/y2fxsiou7t (schematic)
http://www.box.net/public/t49g96bsf0 (TV set)
http://www.box.net/public/ifj8d5gx0e (circuitry)
http://www.box.net/public/a4gm0ifzuy (vertically collapsed picture)

This is a very common part on early sets. I just replaced one in a Hallicrafter 820 that I restored. The one in my Hallicrafter is a stardard Merrit A3000, or a Stancor A8111. It has a turn ratio of 4.2 to 1 with 190 ohm winding and a 900 ohm winding. I would bet either one might get you up and running. It is a common part in many sets, so if you look around for junked sets you might find one you can canabalize. Ocassionally you will find one for sale on e-bay. Or an old tv repair shop might have one. It was a pretty common part.

Good luck

Hi Troy,
please measure the primary and secondary coils of the transformer. If the transformer is bad, you usually get a picture, but vertical deflection is distorted. No vertical deflection might indicate another problem. What is with the currents at the oscillator tube and vertical output tube? Have you measured?
Do you have a scope?

Eckhard