Electric fence

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Crash Manly

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Hi, I am not an electrician but have a problem maybe someone can help with?

I have a recording studio in the basement of my house. the house has steel siding.

Recently I noticed a loud clicking sound every second or so when trying to record some electric bass.

I rigged up a battery powered detector that was basically a guitar cord plugged into a small amp but with the other end free... when I touch the end of the cord I hear static and that click.

Even with the house mains off and all batteries out of wireless devices, I would hear the click.

Outside I would not hear it, until I walked close to the house. There i would hear the click loud and clear by just getting the loose cable end an inch or two from the steel siding, or touching it.

Same for our pole barn that also has steel siding. That is the click goes away when walking between the structures, but is loud and clear again when near the pole barn.

Took me a while but I finally traced the click to an electric fence on a farm a half mile away. I left a message with the farmers wife who seemed incredulous that their electric fence would cause my issues. She said she would tell her husband but as of today they haven't fixed it. I am going to go and offer to help track down the issue, probably arcing somewhere, it is a very run down farm, but i don't think it is a priority with them, and nothing says it won't break again even if they do fix it.

Anyway, I don't want to leave it in their hands...

My question is this... it seems my steel siding somehow collects and amplifies this interference, i don't know how or why, just seems that way from observations, even though I am in a basement surrounded by concrete. The click is loud at any part of the siding, doesn't matter if I am right next to or on the other side of the house from the power service, and I hear it everywhere in the basement and when near the walls anywhere upstairs.

Could somehow grounding my steel siding help? And if so, how would I do it?

Thanks!!!
 
I'm thinking grounding might help as you mentioned. I'm not sure how one would ground steel siding adequately. The click you hear may be an arc jumping a gap between one of the siding pieces and a grounded point. It may be jumping from the earth, to your siding, and then running to your service mast. You would probably have to ground every siding panel. Is your electrical service properly grounded with ground rods? If not, that may be a factor.
 
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Crash Manly said:
Hi, I am not an electrician but have a problem maybe someone can help with?

I have a recording studio in the basement of my house. the house has steel siding.

Recently I noticed a loud clicking sound every second or so when trying to record some electric bass.

I rigged up a battery powered detector that was basically a guitar cord plugged into a small amp but with the other end free... when I touch the end of the cord I hear static and that click.

Even with the house mains off and all batteries out of wireless devices, I would hear the click.

Outside I would not hear it, until I walked close to the house. There i would hear the click loud and clear by just getting the loose cable end an inch or two from the steel siding, or touching it.

Same for our pole barn that also has steel siding. That is the click goes away when walking between the structures, but is loud and clear again when near the pole barn.

Took me a while but I finally traced the click to an electric fence on a farm a half mile away. I left a message with the farmers wife who seemed incredulous that their electric fence would cause my issues. She said she would tell her husband but as of today they haven't fixed it. I am going to go and offer to help track down the issue, probably arcing somewhere, it is a very run down farm, but i don't think it is a priority with them, and nothing says it won't break again even if they do fix it.

Anyway, I don't want to leave it in their hands...

My question is this... it seems my steel siding somehow collects and amplifies this interference, i don't know how or why, just seems that way from observations, even though I am in a basement surrounded by concrete. The click is loud at any part of the siding, doesn't matter if I am right next to or on the other side of the house from the power service, and I hear it everywhere in the basement and when near the walls anywhere upstairs.

Could somehow grounding my steel siding help? And if so, how would I do it?

Thanks!!!
Click to expand...
clarification: The 'click' is on the speaker hooked to your amp witht he guitar cord, correct?
Or is the click something you hear the siding do?

If it is electrical pickup thru the cord and amp, what you will need to do is add a low pass filter to your guitar cords (or on cords to recording media) You want a filter that has above a 20 kHz cutoff 100kH probably do. .

Example similar: many high gain preamps for school and church PA systems back in the 'good buddy' citizen band radio days (BCP_before cell phones) would pickup CB radio chatter when a high power CB truck went by the building witht he PA system - fix was a simple - a 500 pF capacitor at the input to the preamp. There are likely many different filters you can buy on line that just plug inline with the guitar cord - just ask at your guitar store, they should know all about CB radio noise interference, the electric fence is in the same category, easy fix on your end.

Your steel siding, if not grounded, may be a good antenna for the electric fence, so grounding will help as previously stated. .
 
I agree with junkhound that you should try a low pass filter.
...
Crash Manly said:
... Took me a while but I finally traced the click to an electric fence on a farm a half mile away. ... I am going to go and offer to help track down the issue, probably arcing somewhere, it is a very run down farm, but i don't think it is a priority with them, and nothing says it won't break again even if they do fix it.
Click to expand...
The interference is very likely due to the fence arcing over somewhere, as you said. This would involve the same principle used in spark transmitters over 100 years ago. The fencer would charge up the distributed capacitance of the fence wire until its voltage reaches breakdown, and then the spark completes a resonant circuit including the series inductance of the wire. The circuit would ring until all of the energy is dissipated, and then the fencer begins the cycle all over again. The fence wire would probably make a fairly good radiating antenna.

I suspect that you'd be able to pick up the interference with a portable AM radio, at least when it's tuned away from any strong stations.
If for some reason low pass filters are not fully effective, you'd still want to track down where the fence might be arcing so that it can be fixed. If you can show the farmer that it interferes with AM radio, then you might motivate them to fix it by mentioning that the FCC could get involved (not that that would be likely to happen). ;)
To find an arcing point I'd first disconnect the fencer from the fence wire to confirm that noticable clicking goes away. Then disconnect sections of the fence, starting at the far end, until the clicking is significantly reduced or eliminated. While doing this, it would be best to be on a cell phone conversation with someone at your home who can monitor any clicking that is occuring there. If you're monitoring the interference near the fence and the fence charger then it could be harder to distinguish any improvements, and in any case it wouldn't prove that your problem had been solved.
 
Thanks folks! yes jumkhound the click is on the speaker... I do want to try and fix the issue at the source, like synchro says... I need to find a battery powered am radio, I actually don't think I have one anymore! The contraption I was using, a usb powered interface with a guitar cord and headphones plugged in all powered by an external battery, kind of cumbersome. As for the low pass filter, I will look into that as well.. I recorded the click and ran it in the audio analyzer, here is the picture, https://photos.app.goo.gl/rqeesmRGwhNScS1a7 and the click at least shows up as between 1k and 20k, which of course is right smack in the sweet spot for audio... Junkhound do you think the low pass filter would help? I will have to try and find one and see... a quick online search didn't seem to show anything designed for that on a 1/4 inch standard guitar cord, I will have to dig deeper... what about the house seeming to amplify the signal? Again standing outside 20 feet from the house and I can't hear it on my detector... only when I am inside the house or standing right next to the siding outside the house, or right next to the siding of the pole barn, or right next to the electrified fence... I always thought metal shielded against radio waves?
 
Crash Manly said:
... I recorded the click and ran it in the audio analyzer, here is the picture, https://photos.app.goo.gl/rqeesmRGwhNScS1a7 and the click at least shows up as between 1k and 20k, which of course is right smack in the sweet spot for audio... Junkhound do you think the low pass filter would help? I will have to try and find one and see... a quick online search didn't seem to show anything designed for that on a 1/4 inch standard guitar cord, I will have to dig deeper...
Click to expand...
It's very likely that your click is caused by a pulse of RF (radio frequency) energy that has radiated from the electric fence 1/2 mile away. But what you hear and what you see on your audio analyzer is not the RF waveform itself, but a "detected" signal that's proportional to the instantaneous amplitude of the RF signal. In other words, it's the output of an AM detection process. If the RF pulse enters the electronics of your audio equipment, then semiconductor junctions can detect the amplitude of the RF signal and produce an audible frequency output. It's just like a crystal set that detects the modulation from AM radio stations so that you can hear them. The AM detection occurring in your electronics would result from rectification and/or second harmonic distortion of the RF signal.
But ... if you filter out the RF pulse before it can enter any of your sensitive electronics then it won't be detected and cause an audible click.
 
Thanks for the explanation synchro, that makes sense. i would like to try filtering out the pulse, it would be the ideal solution, junkhound suggested a 100khz cutoff... I do not think I could build one and so far haven't found anything online pre-made that I could simply plug my cord into, plenty of the filters seems to have bnc type antenna connectors. But I will keep looking. I spoke to some techs at a competent guitar repair shop in St Paul, but they couldn't help me. Thansk so much everyone for the great responses and help! I will post back if it is solved so you can add to your "solved" knowledge!
 
Crash Manly said:
Thanks for the explanation synchro, that makes sense. i would like to try filtering out the pulse, it would be the ideal solution, junkhound suggested a 100khz cutoff... I do not think I could build one and so far haven't found anything online pre-made that I could simply plug my cord into, plenty of the filters seems to have bnc type antenna connectors. But I will keep looking. I spoke to some techs at a competent guitar repair shop in St Paul, but they couldn't help me. Thansk so much everyone for the great responses and help! I will post back if it is solved so you can add to your "solved" knowledge!
Click to expand...
As a first attempt, a simple ceramic disk capacitor between the signal lead and ground inside the shell of the 1/4" phone connector plugged into the guitar may be enough. Either calculate the size or experiment to find a value that does not reduce the high audio frequencies too much.
In theory a shielded cable with good shielding and metal connector shells should not pick up the fence "signal", leaving mostly the open wiring in the guitar as the source.
It is also important to have low resistance in the grounded conductor and shield at each interface. If you find that the cable itself, not plugged into the guitar is picking up noise, then put a direct box as close to the guitar are possible and balanced low impedance cable back to your preamp or amp using XLR connectors. If your guitar amp needs high impedance unbalanced signal, put a direct box right at the amp input too.
 
Thanks! I did buy a heavily shielded guitar cable but it didn't help, the interference still gets through when it is either plugged into the guitar or when the connector is loose and I touch the tip. I tried a direct box already, as mics connected via xlr do not pick up the interference... but I will try repositioning the box as you described. What would be some values to start with on a ceramic disc capacitor? I think I could handle installing one on a cable, but not sure how to calculate size or find a value...
 
ok thanks everyone, great picture fishin, very very helpful! I think I have plenty of info to work with, I will post any results once I get a chance to implement them!
 
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