If this was continuous, likely related to leakage. If it was a zap, then likely charging of the antenna. I hit this problem making a preamp for my brothers shortwave when he was in the Gulf. His antenna outside charged and you could see a spark from the connector up to an inch long when it was not terminated.
During a sand storm, "ticks" every few seconds could be heard. I've blown few antenna preamps here in Illinois in the winters, I suspect it's related to antenna charging. Another 5 cents worth. Derek. ----- Original Message ----- From: <[email protected]> To: <[email protected]> Sent: Wednesday, December 12, 2007 10:45 AM Subject: Re: stray voltage ??? > Curt McNamara <[email protected]> wrote on 12/12/2007 08:07:16 AM: > >> I admit to not having followed all this -- however I know an engineer >> who works on building issues for people. Supposedly the most significant >> problem is the neutral bonding to ground inside the house. If this is >> done in such a way that significant neutral current flows through the >> pipes instead of the wiring then there is significantly more 60Hz >> magnetic field. >> >> The folks most concerned are those with autistic kids, who seem to be >> more sensitive to this. >> >> The typical fix is to isolate (electrically) the pipes inside the house >> from the main (with a piece of plastic pipe). >> >> If you want any more details please send questions to me and I will >> forward to him. >> >> As to personal experience, as a teenager I used to work on TV antennas >> and found the voltage present at the terminal of a receive antenna on a >> roof was surprisingly strong. Typically I couldn't keep my fingers on it >> and needed insulation. It is possible this was related to weather >> conditions. >> >> Curt > > If you felt AC voltage on the TV antenna (felt a 120 Hz buzz), then most > likely it was due to the TV receiver. Up to a certain time, it was common > to put a Y-cap to chassis ground from both the neutral and hot conductors, > with no safety ground (two wire, non-polarized plug). This forms a > capacitive voltage divider, so the chassis is floating at about 60 volts > AC. The antenna input terminals of the TV were often tied (at 60 Hz) to > chassis ground via a capacitor and/or resistor. Thus there was some 60 Hz > leakage current out the antenna terminals. The rest of the TV was usually > well insulated, so no leakage current was noticeable in normal use. > > Don Borowski > Schweitzer Engineering Labs > Pullman, WA, USA > > - > ---------------------------------------------------------------- > This message is from the IEEE Product Safety Engineering Society > emc-pstc discussion list. Website: http://www.ieee-pses.org/ > > To post a message to the list, send your e-mail to [email protected] > > Instructions: http://listserv.ieee.org/request/user-guide.html > > List rules: http://www.ieee-pses.org/listrules.html > > For help, send mail to the list administrators: > > Scott Douglas [email protected] > Mike Cantwell [email protected] > > For policy questions, send mail to: > > Jim Bacher: [email protected] > David Heald: [email protected] > > All emc-pstc postings are archived and searchable on the web at: > > http://www.ieeecommunities.org/emc-pstc > - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Jim Bacher: [email protected] David Heald: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
