75 Volts off TV F-connector?

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pjm@see_my_sig_for_address.com wrote: ....

The point was there are lots of ways to get voltages w/ low currents from capacitive coupling, etc., that may show up as either measured voltages using high impedance meters or an occasional "feelable" shock that are not dangerous nor code violations nor manufacturing defects/failures...
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As some of you suspected it's my analog volt meter. If I had understood the meter could give false voltage readings, I would have mentioned which meter I was using in my first post, though I did mention it later. The electrician checked the house wiring and there's nothing wrong. The only suspect is possibly the TV tuner, so the next step is to maybe contact a TV repair. One positive thing out of this is I found a very good electrician, after one guy never returned the phone call and another one failed to show when promised.
Anyway, thanks, and as the late great Emily Litella said: Nevermind!
Cheers!
--
Luke


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Luke,
thanks for posting the outcome and I hope it was a lesson to some of the trolls.
Mark
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Thanks to you and other calmer heads who suggested the meter as the likely culprit or who thought it just didn't make sense and was likely not a wiring fault. The suggestion, albeit hysterical in tone, to call an electrician, considering the info I gave and that it is in the end my decision, was not of itself a bad suggestion. And it is Usenet - one gets what one pays for ;-).
Just between you and me <g>, I don't know whether they should be called trolls or flamers. In any case I suspect they have otherwise empty lives.
--
Luke


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don't blame the meter, if you had a new digital meter, you would have similar results, maybe even worse.
A volt meter is designed to measure voltage and is designed to be very sensitve in the sense that it takes very little current. So even some very small leakage CURRENT can register as a high voltage. Like when you get a shock from a dry carpet, that is actually several thousand volts, but the current is very low. so in the appliacne you are measuring the AC line volage trhough the leakage path which is a very weak high resistance path so very little current can flow but it is enough to register on a volt meter. Actually the better the voltmeter, the higher it will register. Voltmeters need more current on the lower scale so when you switch to a lower scale it actually drops the voltage more and you get a lower reading.
What you really need is an AC current meter to measure leakage. A current of a few mA (thats milliamps = 1/1000 Amps) can give you a bad shock. 100 mA = 0.1 Amps can easily kill you.
Most cheap meters unfortuntly cannot measure AC current. They can measure DC current and DC or AC voltage. If you really want to measure AC current, go to radio shack and buy a 1000 Ohm resistor. Connect the resistor across your AC voltmeter leads. Now the AC voltage reading will be about equal to the AC current. 3 volts will be about 3 mA. Note that a ground fault interupter is set to trigger at 6 mA (I think I have that right, I'm sure someone will correct me if it's worng)
Your TV antenna lead is probably grounded somewhere as it should be. Your TV has a fair amount (but probably normal amount) of leakage that you measure and feel. Your mixer has a smaller amount of leakage that you can measure but not feel.
So now you can use your meter and if something measures like you mixer, it is OK, If it measures like your TV, it is OK but has a higher leakage that is in the range that you can feel. If something measures much higher than you TV, I would become concerned.
have fun
( in any case I wouldn't grab onto your mixer or anything else electric while standing in a puddle of water) :-)
Mark
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No, nothing from the mixer with the wet fingers test, even in bare feet on the floor. Guess I could try dumping water on the floor or standing in a metal bucket filled with water, but I think that'd just make a mess for no good reason ;-)
--
Luke


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The TV, VCR, DVD player, and mixer all have two prong plugs. So, unless I'm missing something, I don't see how connecting them to a three prong extension cord to a GFCI outlet does anything, and it didn't :-). The mixer, in the kitchen, is plugged into a GFCI circuit, and I also tested it in the first-in-line GFCI kitchen outlet.
We have a rooftop antenna, no cable or satellite.
Yeah, I could use a good digital voltmeter and an amp meter, but with a 12 year old house filthy with grounded outlets, switches, and new fixture boxes there's no wiring for me to do, frustrating in a way after living many years in 80-100 year old houses <g>, so except for this very odd occurrence it's difficult to justify even that expense.
We still have intermittent TV reception problems. I suspect the TV tuner, or something with the TV. I've gotten a recommend for a TV repair person and will pursue that. Thanks!
--
Luke


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One reason why an analog meter would report different numbers for different ranges - the meter is not a high impedance input. The meter puts a different load on the 'leakage' with each selector change and why I suspected is was a small (milliamp) leakage. Just another reason why a $20 3.5 digit multimeter is preferred over a $10 analog meter.
In the meantime, how to identify the problematic appliance. Connect the appliance (using a long three wire extension cord) to a GFCIed kitchen or bathroom receptacle. Excessive leakage in the TV, et al may trip the GFCI. Now you know which appliance to have repaired.
It could be that the leakage is from your neighbor's TV via your cable. Just another possibility. This should not happen if your cable is properly earthed before entering the building.
You know there is leakage. You know the electrician sees good safety grounding. You now have a tool (that GFCI) to help locate the 'leaking' appliance.
Luke wrote:

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Luke posted for all of us...

--

Tekkie


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Mark, thanks much for taking the time to write a cogent explanation, about what the electrician said, though you gave more detail. You would know this of course, but I've now taken my meter to friends' houses and gotten similar results. Could be a good party trick for the uninformed ;-).
Cheers!
--
Luke


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Test at your friend's house should have been done with same resistors (resistors that would have made so many other posts irrelevant). To obtain a useful number, this was posted previously.:

Your meter reported different voltage numbers on different selector (range) settings. Of course. Apparently was a low impedance meter. A digital multimeter would have reported a more consistent voltage on every range - leaving you less confused. Either way, using those $0.25 resistors would have provided useful numbers that eliminated those so many speculation posts.
Feeling a tingle when touching any appliance is unacceptable. Is it dangerous? Probably not. The tingle suggests one of the required layers of safety is not working properly. If other safety layers fail, then that tingle could become more serious. But again, we have neither useful numbers nor understand why that unacceptable tingle exists.
Luke wrote:

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IGNORANCE ABOUNDS! Troll: don't feed it.
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