[Boatanchors] Xfmr temperature?

[msix@nmia.com]

Richard - Good info. Good pix. Nice work on amp.
I need to look at the primary waveform as I raise the AC
to see if any distortion.
Since the temp varys with primary turns, I'm assuming the
heat is due to a low turns/volt ratio and not a poor
quality core --- altho it looks like they weld all the
laminations together???
When you get a chance perhaps you can measure the idling
temp of the core and let me(us) know...
73 John

On Mon, 12 Jan 2004, Richard Post wrote:
> John,
> I put the 3 volt magnetron filament winding in series with the
> primary.  Same idea, similar results.  Did a current draw check when
> wiring up a pair of unloaded trannies (wired for full wave, grounded
> center tap).  Feeding by variac, the last few volts before 120 caused
> a substantial increase in current draw.  Looked liked a saturation
> point was reached.
> Pic of power supply on web page.
> <http://oak.cats.ohiou.edu/~postr/bapix/813amp.htm>
> 73,
> Rich KB8TAD
>
> At 11:26 AM -0700 1/12/04, <msix@nmia.com> wrote:
> >Testing several microwave xfmrs for an HV supply
> >showed the idling core temp stabilizes around 175F.
> >
> >Adding 4 turns to the primary lowered it to 140F.
> >
> >Wonder if others have seen the same thing?
> >73 John W7ZFB
> >