Re: Rob's flyback circuit

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Steve Mach by way of Terry Fritz <twftesla-at-qwest-dot-net>" <gossamer-at-cox-dot-net>

Rob, In televisions with this type of flyback circuit they use a pp cap from
the collector to common to limit this "retrace"pulse amplitude which also
affected the HV out.Early designs used regular 2 lead caps(which would go
open over time,HV SOARED 60-90KV was not uncommon,turning your tv into x-ray
generator!
IF memory serves me values were .05-.15 uF/2-3 KVdc.
Ceramic and polyester caps are no good,have to use polypropolene.
Hope this helps,
SM
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Thursday, June 20, 2002 12:38 PM
Subject: Rob's flyback circuit


> Original poster: "rob by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<rob-at-pythonemproject-dot-com>
>
> Well, I can't get my own circuit working (the one in the archive
> robflyback.sch).  Blew up 2 2N3055's.  I have yet to remember the secret
> to getting high output from a cheap transistor.  I did get an NTE328 to
> work, but it had spurious HF oscillations, and didn't give really high
> output.  The really suprising thing was seeing 300V on the collector,
> using a 20V DC supply.
>
> As soon as I figure this out I will update the schematic.  Maybe I need
> to get hypnosis to bring me back to my childhood HV days :)
>
> Rob.
>
>
> --
> -----------------------------
> The Numeric Python EM Project
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