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Author Topic: neighbor refuses to upgrade 40 foot long, unshielded, non-twisted speaker wires  (Read 1265 times)

N6AF

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  • Posts: 129

The Subject line says it all.  When he complained about even my 100 Watt HF operation I inspected his stereo hi-fi installation and saw up to 40 foot long unshielded, non-twisted speaker wires running all over his house from a distribution amp.  After trying simple clamp-on ferrites that didn't help I explained he needed to change to shielded, twisted pair speaker wires.  But he absolutely refuses to change out his "antenna system".  Threatened me in the street last week yelling "Fxxk you !  I don't have to change my speaker wires! "  I tried the diplomatic approach, providing free engineering evaluation and recommendations.  Ridiculous.  Retired EE here (36 years Harris Corp).  Even a K3 or TS-590SG at 100 Watts into a resonant OCFD at 35 feet bothers his "hi-fi antenna farm".  He's about 250 feet from my property.  I talked to the ARRL Division Manager and I then filed a complaint about the complainer with the FCC so if he files a complaint with the FCC they already know my station is clean and the issue is on the complainer's end.  First time in 51 years of operating.  Frustrating!
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AA4HA

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You can't cure stupid.

From what you have written you have done all that is expected of an amateur operator to work with the other party to give solutions to their interference. You have even gone well above-and-beyond that by offering free (but expensive if you were still in the business) services to mitigate this issue.

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Ms. Tisha Hayes, AA4HA
Lookout Mountain, Alabama

N0GV

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Hmmmm,

Time to break out the PSK31 and run 250 Watts from a 1 kW amp into your antenna. This should really annoy him! Seriously, the field strength at 250' from 100 Watts is not sufficient to cause issues and is well below the safety standard limits. He has a lousy system and that is a fact. BTW - his pickup is probably NOT from the speaker wires but from the power line to his amp.... Unplugging the amp and if the pick up continues then it is the speakers.... shunting each end of the speaker wire with 1000 pF should help.....

Grover
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KB6DYA

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  • Posts: 187

Hi Just a suggestion. Have you tried a good quality choke at the feed point of your OCFD antenna and maybe at the transmitter end & a good RF ground. I am in know way tryiny to shap shoot you. I am not as quilified as you are being a Rf enginer.
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K1KP

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  • Posts: 144

You can catch more flies with honey....

After letting him cool off, you might offer to provide some discrete filters for connection at the distribution amp. If you're getting into the amp with clean RF, the problem is likely to be RF picked up by the speaker wires getting rectified in the output stage of the amp. As a retired EE, you should have the expertise to build some simple balanced low-pass filters out of discrete Ls and Cs which will pass audio but absorb/block RF. I don't see how he can object if you provide the filters.

Folks often just assume that throwing on a ferrite bead should fix every problem. While this frequently works, you have to remember that ferrite beads on cords and speaker wires (both wires) work to block common mode RF. But in this case it could be differential mode because the wires are not twisted pair. Additionally, bear in mind that ANY effective filter has TWO elements: One that serves to block the series passage of the undesired signal, working against a second that serves to shunt the undesured signal to ground. Ferrites add a series impedance to block the RF, but if the shunt path is not low impedance, it will take an astronomically high series impedance to provide effective reduction.

With a discrete filter you control both paths and can be assured of excellent attenuation of RF getting into the amp.

Might be worth it to keep peace in the neighborhood. Often the best friends are converted enemies.

-Tony, K1KP
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W9IQ

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Be cautious about applying capacitive bypass on the speaker leads of modern audio amps. Even modest capacitive loads can cause them to break into a destructive oscillation. That will not cool things down!

- Glenn W9IQ
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- Glenn W9IQ

God runs electromagnetics on Monday, Wednesday and Friday by the wave theory and the devil runs it on Tuesday, Thursday and Saturday by the Quantum theory.

KB1GMX

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  • Posts: 2252

First do not touch his stuff, if it breaks its your fault, even it the house falls down on it..

The rules are simple you have a license to transmit.  Your transmitter is
clean and of modest power.   The defect is exclusively in his system.
In short your doing nothing wrong, its his problem.  If he asks for help
get a third party to assist as a witness.

Generally unless you in the repair business you will suffer pain with
that sort.  Even then the business absorbs the grief.

You cannot argue with an unreasonable person, you always loose.

Allison
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N0GV

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Be cautious about applying capacitive bypass on the speaker leads of modern audio amps. Even modest capacitive loads can cause them to break into a destructive oscillation. That will not cool things down!

- Glenn W9IQ

Yes, this is true, on the other hand 1000 pF isn't going to change things - if it does just putting 40' of unterminated speaker wire on the output of the amp will kill it just as dead....

On the other hand, at those power levels and distances I would be unsurprised if the rf was coming in on the power leads. Speaker wire is pretty well balanced after all....

Best bet it to simply take a spectrum analyzer sweep of your output across the street from him and record it with a witness. If the transmitter meets spec then the problem belongs to the idiot - let him keep it for himself.

Grover
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KB8VUL

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First do not touch his stuff, if it breaks its your fault, even it the house falls down on it..

The rules are simple you have a license to transmit.  Your transmitter is
clean and of modest power.   The defect is exclusively in his system.
In short your doing nothing wrong, its his problem.  If he asks for help
get a third party to assist as a witness.

Generally unless you in the repair business you will suffer pain with
that sort.  Even then the business absorbs the grief.

You cannot argue with an unreasonable person, you always loose.

Allison

This is my vote too for what it's worth.  You are DONE.  At the point that he's cussing you in the street, you are NOT gonna get through to him.  DO NOT change your operating methods or style to either appease or further enrage him.  He will no doubt call the FCC an number of additional times and may resort to trying to involve the local authorities once the FCC is non-responsive.  You need to DOCUMENT all of this as best you can so when the local cops show up you can hand them your federally issued operators license, your EE diploma and the standing record of what has transpired.  The FCC will not show up for a nonsense complaint but once to verify there is no violation.  Since they have already, if they provided documentation have that as well.  Once he badgers the cops a bit, they will get tired of his antics and issue HIM a warning to stop.  If he continues then they will cart him off for an overnight at the local jail.  At THAT point, you go to court and get a restraining order against him.  Yes,it will further enrage him. Once he violates that about twice, the issue will go away when he goes away to real jail and not just a sleep over in the county or city clink.  DO NOT confront him. DO NOT challenge him.  Leave him alone and operate above bar.  And for Gods sake do NOT leave your house with an open carried firearm when he is around.   HE WILL claim you threatened him with it and you WILL have a problem until it's worked out.  But you other option is once he's pushed enough that they will grant you an order of protection against him, you can look in the county auditors web site and see how much his house is worth and sue him for that amount plus 20%.  That will also get rid of him.
 
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NA6O

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I’d agree you’re pretty much at a dead end until the neighbor cools down. Here’s a good reference page on this particular situation from ARRL. http://www.arrl.org/audio-1

Gary NA6O
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KC6RWI

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Although it maybe your transmitter, could the interference or noise be coming from another source?
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KD6LM

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I published this on e-ham back in 2001 regarding the Bencher YA1 low pass filter. I have no idea why it worked but it did. If you have a low pass filter (or can borrow one) give it a try.

When reading the recent survey on e-ham, I noticed that over 50% of all hams have had some sort of RFI problem in the past. I was thinking how lucky I was not to have experianced that, when my downstairs neighbor stopped me on my way upstairs to my new apartment to complain about voices coming out of her telephone and stereo. Looking inside her apartment I could see I had a problem: her stereo consisted of one of those piece of junk plastic all-in-one units, with speakers placed all around her apartment connected by long runs of unshielded speaker wire placed under the carpet. The telephone was a $25 cordless unit.

My rig is a Kenwood TS130s running through a Kenwood 130 tuner into a 85' longwire in the trees (I usually operate 15-80). I use a T-Kit (Ten-Tec) counterpoise for my RF ground as I live on the second floor of an apartment building. My neighbor lives right below me. Longwires are notorious for RFI problems, a reputation well deserved as I just found out. I decided to buy the Bencher YA1, the most expensive RFI filter I could get (about $25 more than most), but also having the best specs. Since I have started using the YA1, I have had no complaints what-so-ever, nothing. I consider my situation to be the acid test of a RFI filter, I can't imagine a worse situation. The Bencher solved solved my problem, and has allowed my to stay on the air. I give it my highest recommendation.
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N7EKU

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Hi,

From what I've read, simple clamp-on ferrites are not near as effective as a toroid with many wraps around it. This would certainly be a lot easier to try than changing all the speaker wires to shielded types.  Hopefully he has enough extra length available so he can try this.

He uses a distribution amp in his house?  So is this actually a PA system with high impedance lines?  If so, what needs to be done may be different as I have no experience with that.

73
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Mark -- N7EKU/VE3

WA1UIL

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First off  YOU doing/adding/modifying anything to his equipment sets you up for a real crap storm should anything EVER go wrong with ANYTHING at his house. Houses never burn down from faulty pluming and should he ever have a fire, YOU are the first person he's going to tell the Fire Marshal about. Like everyone else said, move on and ignore him.
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K4FMH

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First off  YOU doing/adding/modifying anything to his equipment sets you up for a real crap storm should anything EVER go wrong with ANYTHING at his house. Houses never burn down from faulty pluming and should he ever have a fire, YOU are the first person he's going to tell the Fire Marshal about. Like everyone else said, move on and ignore him.
Hi Frank,

I really wish I could argue with your brass-tacks logic here but I simply can't. I know the ARRL and most suggest taking the "diplomatic" approach so that amateur radio always has a Happy Face, etc. But you are indeed correct at the bank-shots that can carom off of going beyond a certain point in trying to help. Getting verbally threatened is that line.

The final thing I would advise on this, if the neighbor persists in contacting the OP, is for the OP to request a photo of the manufacturing plate of the equipment (not the speaker wires) receiving the interference. No doubt, it's Part 15. Once in receipt of that, the OP could mail a copy of the Part 15 segment about "not creating any interference and accepting all other interference" along with the picture of the manufacturer's plate stating Part 15 back to the neighbor (certified delivery suggested). In that letter, stating that you've tried to help but the legal status is that his consumer equipment is at fault as per Part 15. Should the neighbor wish for you to help solve the problem, your advice is to purchase some double shielded audio grade cabling for his speaker system OR go to bluetooth or WiFi speakers.

Just a thought...but stay safe and aware from further confrontations if at all possible.

73,

Frank
K4FMH
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