On Dec 19, 10:29*pm, "Phil Allison" wrote:
"pfm"

I was working on an CRT TV using an isolating transformer. I happened
to measure the voltage between the chassis 'dag' and a nearby metal
fixture and was surprised to find 75Vac. Without the transformer the
reading was 110Vac.

Something is wrong, right?

** Wrong.

DMMs typically have 10 Mohms impedance across the leads when in any of their
AC volts ranges *- *so a reading of 75 volts AC indicates there is leakage
of about 7.5 uA of AC current.

Equates to about 600 pF of capacitance ( primary to secondary) in the iso
tranny.

Try connecting a 0.1 uF cap from the TVs chassis to ground *- *that should
swamp the effect.

.... *Phil

Thanks Sam and Phil, you were right, it was just stray voltage.