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Transformer overwind

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N_Cook

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Jun 29, 2011, 3:45:55 AM6/29/11
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Hypothetical as enough space for a second Tx this time. Open construction
toroid Tx mainly 45-0-45V 400 watt and 10 turns of fine wire to give an IC
supply of 35V,0.1 amp ac, over the thick windings and under the outer
taping.
No exact replacement Tx available. If you used a bulk standard 45-0-45 400VA
Tx and then over the outer taping you wound some turns , would you need more
turns ?
Then added taping over that overwind and allowance/padding for mounting
forces over the end faces.


Phil Allison

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Jun 29, 2011, 3:51:32 AM6/29/11
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"Nutcase Kook "

>
> Hypothetical as enough space for a second Tx this time. Open construction
> toroid Tx mainly 45-0-45V 400 watt and 10 turns of fine wire to give an IC
> supply of 35V,0.1 amp ac, over the thick windings and under the outer
> taping.

** Need way more than 10 turns.

> No exact replacement Tx available. If you used a bulk standard 45-0-45
> 400VA
> Tx and then over the outer taping you wound some turns , would you need
> more
> turns ?

** No.

You get a fixed voltage per turn - depending on the core size.

A 1 square inch core gives about 0.2 to 0.25 volts per turn - the bigger
the core, the more the volts.

Simple trick is to loosely wind about 10 turns on the tranny and check the
resulting voltage with a DMM.

Then you know the turns per volt.


... Phil


N_Cook

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Jul 2, 2011, 2:20:58 AM7/2/11
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N_Cook <div...@tcp.co.uk> wrote in message
news:iuel50$1pm$1...@dont-email.me...

3.5V,0.1 amp ac for CCD display , poor printing of schematic


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