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Message-ID: <00bc01ca059d$bd1bcac0$0900a8c0@AM>
From: "Alan Melia" <alan.melia@btinternet.com>
To: <rsgb_lf_group@blacksheep.org>
References: <20090715.172949.3828.1.riese-k3djc@juno.com>
Date: Wed, 15 Jul 2009 23:40:00 +0100
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Subject: Re: Re: LF: Microwave oven transformers
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Great but of "recycling" Bob :-))
Alan

----- Original Message ----- 
From: <riese-k3djc@juno.com>
To: <rsgb_lf_group@blacksheep.org>
Sent: Wednesday, July 15, 2009 10:28 PM
Subject: Re: Re: LF: Microwave oven transformers


> 
> On Wed, 15 Jul 2009 21:59:44 +0100 "Alan Melia"
> <alan.melia@btinternet.com> writes:
> > Hi Ken yes I appreciate the usage. I was a little concerned that if 
> > the
> > transformer was not designed for that kind of use it might not 
> > necessarily
> > have sufficent insulation from that end of the winding to ground to 
> > survive
> > the different stresses of of bridge rectifier. However Bob says he 
> > has been
> > using one like that for years so I guess they must have been 
> > conservatively
> > designed. I have had problems with transformers parallel primaries 
> > and
> > series secondaries ( a common way of getting high voltages for 
> > valves ....in
> > my youth :-))  ) breaking down under the voltage stress. I have 
> > several
> > transformers I salvaged from MOs and I now feel a lot happier about 
> > their
> 
> I was able to mount a porcelain stand off at the same hole the ground lug
> was mounted to ,, I think I then added a gob of clear silicon from the
> local
> hardware store,,, was surprised that it held up,, but it did
> 
> Bob K3DJC 
> 
> 
> > use in HV PSUs. In the 50s.60s I was brought up with thick 
> > insulation and
> > porcelain standoffs :-))
> > 
> > An interesting thread.
> > Best Wishes
> > Alan G3NYK