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recommendations for large flyback models?

Quote:

Originally Posted by Eric57 (Post 3217391)

Iwhat models/ manufacturers can you recommend for flybacks with secondary sizes of 3" diameter (9"+ circumference) or more

It may help people to identify what you've got to post up some good clear pictures of it , with a common item in the shot for size reference (I use Bic lighters a lot , since everybody on earth has a good idea of what size they are)

What are you using it for?
(Tesla coil?)

It will be more helpful if you can give any hint of a spec such as voltages involved, as well as the application.

When you say the unit 'burned out', did it physically smoke? If not, how did you determine it's the fly that's bad and not some other component? Open winding? If no open winding, did you test it on a ringer?

Quote:

Originally Posted by Eric57 (Post 3217415)

No, a high voltage power supply. This is the design I have with the burned out flyback I pictured above. Current is limited, so was hoping for a larger flyback so I can eliminate the multiplier and get more current this time. Some of the early color flybacks apparently were large and capable of 25- 30 kV output which is what I am looking for ideally.

I would think that whatever color sets of the late 60's/ early 70's did not use triplers and their flybacks put out the 25 kV+ by themselves would be the ones I am looking for, without the built in rectification of course.

You have some misconceptions about your old failed supply....your burnt up flyback was not a type that was meant to use a solid state trippler. It had a HV rectifier top cap connector on it so was a tube rectified type...by around 72 most makes had switched to tripplers in their solid state and tube/SS hybrids. Most makes stopped selling sets with tubes by or before 1975.
Using a trippler with a non-trippler fly like that will either short the trippler (they will sometimes straight rectify their input when they short and could feign normal opperation while loading the fly to death in such an application as a home brew power supply), or require you to drive the flyback much less than normal and possibly have lower current output.

If you want more than 1mA it really would be better to get a modern or even used neon sign transformer (last ARCI swapmeet I got a used one for $1) or something similar.

Also it can be hard for us TV collectors to find the flys we need...It would be better for future maintenance of your supply and for the collector community if you considered something else...

I agree with what Electronic M said.
Tripplers contain capacitors and diodes. The diodes and capacitors have a maximum voltage they can withstand. Diodes also have a limit on the maximum current they can handle. The capacitors have to charge through the diodes and the charging current depends on the size of the capacitors as well as internal resistances in the devices. The bigger the capacitors the more current the trippler can output but also the charging current is higher.
Flybacks can only output so much current, I doubt even a color flyback could stand more than 1.5 ma without burning out. You can't reliably predict how much voltage and power a flyback can handle by the size of the secondary winding. The cross section area of the core also limits the power. Even the frequency the transformer is operating at effects the output, the secondary is actually operating at much higher frequency than the 15,750 Hz horizontal because it is a narrow pulse.
The flyback circuit is something that evolved over time for one purpose and the design is complex. Neon sign transformers are simpler as is another device called a oil burner ignition transformer (those are probably harder to find). Still another idea is an old automotive ignition coil and transistor drive circuit. You could build you own trippler circuit using parts that you know the specifications on with the alternate transformers. Do be VERY careful with these HV supplies, they can be lethal.

What do you use your HV supply for? As I said before, knowing the application may help to find the best device for the job.

And, flybacks are a non-renewable resource.