NeoTec NT-35E Could it be the FlyBack?

RC

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I have a NT-35E Chassis attached to a 38" Tube out of a Hydro Thunder dual focus pots (MRCFT-455 Flyback) that has thrown me for a loop. Symptom was Dark blurry Picture no color red. I re-capped chassis found one cap popped C426 (250v 1uf) and Q905 Transistor bad (C3955) tried to cross no luck talked to HAPP tech said (C3956) would work would have to replace all 3 I did so.
Now I have the OCP ticking and it still pop's the cap C426 ( 250v 1uf ) and no Picture?

Does anyone have an Idea? does anyone have a data sheet on the Transistors original C3955 Vs. C3956 (NPN or PNP)? or could I be fighting the flyback?
 
I had the same problem on a NT-3501

Check the ultra fast diode attached to that cap. When it goes the cap explodes. Also check all the mylar caps next to the large diodes. They split on the ends due to the heat.


http://forums.arcade-museum.com/showthread.php?t=82438

Here was the fix

"Just had a chance to work on this again. Found diode D404 next to the flyback was shorted (this caused C246 to blow) and Capacitor C423 (0.94Uf @400V film) was open. Also had a 470K resistor on the small board that was open. Replaced all of those parts installed a cap kit and also had broken solder joints on the large diode next to C423 and the connector going to the yoke. Now everything is working 100%."



2SC3955 can be found here. http://www.electronix.com/semiconductor-2sc3955-p-3224.html
 
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Regarding the Ultra Fast Diode

Thank you for the Input.
I checked the D404 Diode in circuit and it reads .010 both directions. My Schematic is hard to read do you know the value of this diode or component numbers?. The Mylar's seem to be ok even though is has been hot in this area I do not have a compacitance Meter to test with.

As for the transistors C3955 Vs. C3956 The link you provided looks like a good source for parts but they did not have a data sheet that I could find on these 2 transistors just want to verify the voltages and if they are NPN or PNP
 
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