HOT chassis

[Scott Johnson]

Barring any dielectric failure,you might want to check to see if there are
any bypass caps to ground from the AC line. these are present in many
military and commercial receivers, and will bit you if the chassis is not
grounded.
73,
Scott

-----Original Message-----
From: Boat Anchor Owners and Collectors List
[mailto:BOATANCHORS at LISTSERV.TEMPE.GOV]On Behalf Of Collin Collier
Sent: Thursday, August 15, 2002 11:12 AM
To: BOATANCHORS at LISTSERV.TEMPE.GOV
Subject: HOT chassis


Hello,
I have a NC-57B project and it is going along fine. I have come across a
problem and could use some help. This has a transformer type power supply
and a two wire power cord. When plugged in one way (with relation to the
hot and grounded wire) the chassis is hot with the power switch turned
off and goes to ground potential when the power switch is turned on. With
the power cord plugged in the other way the chassis is OK and then when
the switch is turned on the chassis is hot. I was checking this with the
volt meter and had 117 volts. I then disconnected the AC line bypass
capacitor and the voltage dropped to 90 volts. I can not see anything
else in the circuit to cause this condition. A check with the ohm meter
shows everything OK, nothing is grounded to chassis. Any ideas? I will
continue with this problem but am temporarily stumped..... Thank you.


"73", Collin / N4TUA
Old Timer's Radio    :~)

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