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Output from flyback transformer question? Answered

I scrounged and old crt flyback and I have set up a small transistor-driven oscillator to put power into the primary. It works too, but I don't know if the output is AC or DC. I think it may have a rectifier in it, but I'm not sure. Is there an easy test to determine whether it is AC or DC? I'm planning to use it for a tesla coil, but I want to know the output wave form first. Some sort of pulsed DC would as be acceptable for my uses as well.  Does anyone know what I can do to determine the output wave? 


(PS: I don't have an oscilloscope)



8 years ago

Depends if you are feeding it AC or pulsed DC. if you are simply pulsing the DC input you are getting pulsed (intermittent) DC output. If you are in fact feeding it positive then negative voltage (with an h-bridge) then you'll be creating crude square wave AC. Alternating in AC refers to the + and - actually switching. Transformers work on the principle of CHANGING electric fields induce CHANGING magnetic fields - Pulsed DC has the same effect on a transformer as true AC, but only at half the voltage (zero-to-voltage rather than negative voltage to positive voltage).


Answer 8 years ago

No, because the coil is experiencing currents that vary from 0 to some value and back again. Where is that measured from ? On the primary, you can say "oh yes, this is from the ground line, but from the point of view of flux in the coil, flux goes up, flux goes down. Switched properly there is no direct flux in it.


Answer 8 years ago

I guess so :) I was considering it from the point of a common ground or neutral - which isn't a requirement of a transformer.


8 years ago

Out = in, generally as frollard says.
Small transistor-driven oscillator should give you pulsed / rippled DC.
Now, I haven't got my soldering iron ou to try it (yet), but how about this oscilloscope?