IIYAMA MT9017 only vertical 1cm band

The choke coil should read low resistance. If it does it is probably not bad. It sounds like the problem is in the vertical deflection circuit. Is there an IC for vert deflection? I would look in that circuit. Good Luck. Scott

I do not agree with you : i have vertical line, so vertical circuit and hight voltage (separe circuit) seem good. The problem is realy in horizontal deflection : two transistors died , the main HOT , collector directely connected to the horizontal deflection coil, and correction one that provides variable B+ via choke coil. to collector of HOT . This coil (it is a transformer), shows 0.3 ohms in primary, 0 to 0.1 ohm in secondary (use for regulation) but i dont have a precise ohmeter for this range.May be a short turn somewhere (this coil normaly support 900V pulses). All other components seem to be good. I want to try a swap of choque coil, but I cannot find a replacement.

Olivier

I have solved my deflection problem by rebuilding the choke coil that was short (and replacing the 2 HOT transistors that died)and now I have a good image on the display when I power on. But I think there is another defective component somewhere in B+ regulation circuit, because B+ is quickly growing and screen become lighter and I have to shut down power to not burn other components (a fuse resistor already burned). I have only 10 seconds to make measurements, so it is not easy to find what is wrong. No evident died component.

Any idea ?

Thanks

On Thu, 28 Sep 2006 21:35:17 +0200, OGT Has Frothed:

Put it on a variable ac supply.