[TMC] XFK - AC leakage to chassis

[Nick England]

Preliminary results are that Roy gets a gold star on his report card.
I disassembled the heater and ran it for a while - I now have a toasty warm
block of aluminum and my Simpson 260 doesn't budge when measuring from
aluminum to AC line.

In case you are curious, here's what the innards look like:
http://www.navy-radio.com/rtty-keyer.htm#oven
That's a thermostat next to one of the two 600 ohm/20w heater elements.

If this problem rears its ugly head in the future, I'll swap out the
crystal oven heaters and try them - unfortunately that involves removing
the power transformer whose terminals are buried beneath other wiring.......

Thanks to all,
Nick England K4NYW
www.navy-radio.com


On Sat, Aug 1, 2020 at 1:05 AM Roy Morgan <k1lky68 at gmail.com> wrote:

> It’s also possible now that I think about it, that the heater you have has
> gotten damp, and running it for a while would drive out moisture that Is
> causing the leakage you detect.
>
> > On Aug 1, 2020, at 1:00 AM, Richard Knoppow <1oldlens1 at ix.netcom.com>
> wrote:
> >
> >    Is it possible the heating elements are the same, that is could you
> put the good one in the 200Khz oven?
> >
> > On 7/31/2020 6:57 PM, Nick England wrote:
> >> I started to resurrect an XFK and before applying power checked for
> >> possible leaky AC line bypass caps - Uh oh - measure about 50K ohms
> from AC
> >> line to chassis.
>
> Roy Morgan
> K1LKY since 1958
> k1lky68 at gmail.com
>
>
>
>
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