High Pass Filter

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smog515

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Forest Park,, GA
I have a neighbor who is fully licensed by the FCC to operate a short wave radio (or whichever is necessary to reach international destinations). He's broadcasting @ 28MHz (7-28MHz)

He's had his antennae up for about a year and I've never experienced interference until we lost powerLast for over 15 hours. Out of the blue the next weekend I began picking up his calls through my TV...very loudly. I have a Comcast digital converter with wired cable (not wi-fi) I went to let him know and he said it wasn't happening to his own TV's. He thinks it's my old TV.

I have an old, fully functioning, RCA Entertainment Series model analog V, which I'm pretty sure it's over 10 years old. I unplugged the TV and put it in a different receptacle and he also suggested I tighten up all my cable connections, which I did. I have other analog TV's and it wasn't coming through any of them.
Once I did that, the interference went almost down to '0'. You would have to stand up and put your ear on the TV to hear anything.

Then the next day Sunday, it began again...very loudly at first and then somewhat lower, but still loud enough to interfere with my TV viewing.

When I went to let him know, he said he would contact the FCC to see what their recommendation would be - they told him (and myself when I called) that I needed a High Pass filter. I purchased one but it didn't work. Would you have any recommendations?
 

wyShack

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EMI is always somewhat a game of cat and mouse. First is your neighbor operating on more than one band or just ten meters (28 MHz).? What power level is he using? Normal power is about 100 watts and if that is what he is using I would suspect you are experiencing rectification (your set's audio section is 'picking up' the RF. If so a high pass filter might not help.

Is the TV well grounded? If you are getting direct pick up some kind of shielding may be needed but another thing to try is putting RF 'chokes' on power and/or audio leads for the TV.

Would need more details to go further.

Hope this helps
 
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jim202

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New Orleans region
Request that your ham neighbor install a low pass filter on the antenna port of his radio transmitter. There could be some spurs being transmitted by his radio that can cause the audio interference your having.

How do I know, been there and had to do it myself. The more transmitter power he is using, the better filter he needs to install. My next door "Mr. Wilson" type neighbor was complaining. He watched me put up my dipole antennas and started complaining the same week. I asked him if he was having any issues with his cable feed. He asked why. Told him if he had any loose connections or Internet problems, it was probably a problem with his cable feed.

Guess what? The next week the cable service tech was out there and messing with the connection on the pole out back and at his house. Haven't heard from him since with me causing any problems with his TV.

So it may not all be the cause of a ham transmitter. But to be on the safe side, a low pass filter always makes for good neighbors.
 

prcguy

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So Cal - Richardson, TX - Tewksbury, MA
Do you hear your neighbors voice very clearly or is it a garbled spacey sounding voice that you can't quite make out? If you hear it clearly then your neighbor is probably using AM mode which is most common to CB radio and a few discreet amateur frequencies in the 80m and 40m band. Single Side Band or SSB is the most common voice mode used for HF amateur radio and you can't make out the words when it interferes with stuff.

Since CB is way more common than the very small number of amateur operators using AM mode, I would suspect your neighbor is causing interference with a CB. A stock CB can rarely cause a problem but when used with an illegal amplifier or a higher power amateur radio is used illegally on CB it can easily come through older analog TVs. Your neighbor might not be telling the complete truth about what he is using and he may be operating illegally.

Ask your neighbor what frequency he was using at the time you had interference. Ask what kind of license he has and get the call sign. When confronting CBrs in the past I've heard them boast about being "fully FCC licensed" but a legal amateur operator will usually say I have an amateur radio license, so your neighbors statement about being licensed is a little odd and possibly misleading.

Does he have more than one antenna? Can you take a picture and post it here?
 

smog515

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Forest Park,, GA
WyShack - Ok, all he told me yesterday is that he was operating from 7 - 30 meters, but he didn't tell me how many watts.

He's had his set-up for over a year, I only started picking up the interference after the Irma power outage which lasted 12 hours back in September. Other than that I had never had any problems. I have other 2 analog TV's, one digital TV all connected to cable and none of them are picking up the interference. I am watching TV via Cable. His signal is digital.

Not understanding what you mean by putting RF 'chokes' on the power lead to the TV (I have no audio leads to the TV directly, I do have a VCR and a DVD player hooked up to the TV.

Does that help?

Jim 202 - I had suggested that maybe the pole suffered some damage with the power outage, but FCC suggested the high pass filter before attempting something else. He already made it clear yesterday that he couldn't install anything on his end..maybe he's not familiar.
 

Golay

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check it out

I'm a little taken back that the OP is the one troubleshooting this issue.

Am I the only one that, if my neighbor came knocking with interference issues, would take the ball myself in resolving the problem? I would be buying the filters. I would be the one bringing in, and working with the cable and power companies. I would be bringing other hams over to hold my hand over things I'm not "familiar " with.

He says he's on 7-30 MHz, so the dude's neighbor has to be a General, right? Yet he's unfamiliar on how to resolve issues? Maybe he didn't pass Section G4C of the General Class Exam "Interference With Consumer Electronics".

Tell ya what smog515. If you're comfortable doing it, print this out. And show your appliance operating neighbor that a fellow Ham thinks that as a FCC licensed Amateur Radio Operator, he has a responsibility to GET familiar. And to do all I said in the second paragraph.
 
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prcguy

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Eliminating radio interference requires knowing some things like the frequency range of the offending thing, how the interference is getting into your thing, like through the antenna or through the power lines or direct radiation into the thing, etc. Only then can you consider how to remedy it and know what might fix the problem.

Right now don't add a high pass filter or chokes to your power cables because you don't know what is causing the problem yet. Doing those things would be like trying to diagnose your broken car with a blindfold on and randomly swapping parts like the carburetor, battery, a piston, starter, whatever.

Speak to your neighbor to find out what frequency he uses that causes you problems. Find out how much power he is running. Does he have a new antenna or radio or amplifier or is he operating on a new band? Something probably changed between the time you had no interference and now, find out what that is. Once you have a list of facts about your neighbors radio stuff you can then pick a direction to go or let us know what you find and we can recommend some meaningful things to do.
prcguy

WyShack - Ok, all he told me yesterday is that he was operating from 7 - 30 meters, but he didn't tell me how many watts.

He's had his set-up for over a year, I only started picking up the interference after the Irma power outage which lasted 12 hours back in September. Other than that I had never had any problems. I have other 2 analog TV's, one digital TV all connected to cable and none of them are picking up the interference. I am watching TV via Cable. His signal is digital.

Not understanding what you mean by putting RF 'chokes' on the power lead to the TV (I have no audio leads to the TV directly, I do have a VCR and a DVD player hooked up to the TV.

Does that help?

Jim 202 - I had suggested that maybe the pole suffered some damage with the power outage, but FCC suggested the high pass filter before attempting something else. He already made it clear yesterday that he couldn't install anything on his end..maybe he's not familiar.
 

AK9R

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Something probably changed between the time you had no interference and now, find out what that is.
Or a new operating mode. If the neighbor was running mostly SSB and is now running AM or some data mode that is nearly 100% duty cycle, that could change the nature of the interference.
 

SCPD

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Virginia
Reading the information that was post'd by you, Smog, I came away with a few questions.
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Like the others, I ask-
"Smog.... have you asked your neighbor if he has changed anything?.. is he operating on different "bands," using a different type of transmission (like AM, or "sideband," FM,) is he now using a higher power, or a new radio set?"
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Has he done anything new to his antenna(s)- repair'd/replaced anything-- and how close to your house are they?.... these are among the myriad of questions I have.
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You and your neighbor share a mutual problem, and he shares a great deal in the mutual responsibily of solving it... which goes far beyond instructing YOU to install 'high pass filters,' 'chokes'- whatever.
My guess is that if he is telling you do this, and had to contact the FCC for advice- he hasn't a clue-- what to do, or about anything radio.
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Enuff harsh comments about your neighbor-- what I'd do is ask him to reset, redo, return- what ever- back to the same operating status before your storm-- the same 'band(s)' power, emissions etc.- and see if the problem persists. That will give you both a point to start scientifically invesitgating what is going on.
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It persists?.. then Ask HIM to check over his antenna for any loose connections, corroded contacts, loose grounding points. Don't go tearing into your TV.
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If he is serious about this problem, he will work with you-- running tests and doing more than 'contacting the FCC' (which in his case may be nothing more than a few keystrokes on their web site.) That license he has comes with a certain responsibility to you to fix this.
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Get some more information, after running some test with him, and the guys here on this forum can better advise you.... :)
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______________________________________________________
;
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TVI- I thought it was a dead issue... but I guess somethings never go away.
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A story:
I grew up with it- my father and grandfather were both great 6 metre fans.
In the days before cable, satellite, FiOS lines and analogue TV's with the crappy-ist front ends- Television and ham radio did not mix !... especially 6 metres
..
For what seemed like an eternity, my father had this 6 foot monstrosity of a 'homebrew'd' 6 metre linear- a full-plus kilowatt masterpiece with a pair(!) of 4-400's glowing behind a glass window in the top panel of a relay rack cabinet. He used this back in the days when most 6 activity was still emerging to sideband- and it put out the most remarkably powerful class AB1 AM 6 metre signal!
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The TVI problem was-- looking for a good word-- Stupendous !!- for not only the front end overload issues on those barn-wide old TV front ends, but the nasty harmonics passing thru that amplifier.... for his exciter ran on 8Mhz, and multiplied up..... oh, what a ripe combination for TVI.
--- LP filters galour-- didn't even touch it.
(finally switching to 25Mhz solved some of the problems, but building stable VFO's at that frequency posed there own issues in those days.)
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Enuff story--
........ needless to say, I know where-of I speak. And strangely my sympathy is with the television view'r today... for I so remember the many tales of my mother trying to watch TV while my dad 'did his radio thing'...... :)
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.............................CF
 

majoco

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New Zealand
I have a neighbor who is fully licensed by the FCC to operate a short wave radio (or whichever is necessary to reach international destinations). He's broadcasting @ 28MHz (7-28MHz)

Is this actually what he said? It doesn't sound the sort of language that a 'real' ham would use - are you sure he's not just a CB operator? Most hams would be quite worried that they were causing interference and move heaven and earth to cure it.

I had a 'problem' with a neighbour who saw me putting up a new antenna - pretty soon he was complaining that I made interference on his tube AM radio. I asked him to keep a log of when the interference was there and we would compare it with my log - which at that time I was legally obliged to complete. His log was ridiculous - even had interference when I was at work in the daytime! His radio knowledge was almost zero, I helped him track down the "interference" - a loose joint in the wire antenna he had strung out to his shed. He was from some unpronounceable place in eastern Europe trying to listen to 'back home'.

But the moral of the story - keep a log of the interference and what it sounds like - get him to compare with his logs or his memory. It's his duty to not interfere with you, not the other way round - you need to do nothing - if the noise persists then you can contact the FCC.

My guess is that the Irma storm has loosened up a metal-to-metal joint somewhere which may be arcing when he transmits causing re-radiation of the signal on higher harmonics - right up to the TV frequencies.
 
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rescue161

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I put up an antenna for a UHF FM repeater once when I was starting out in installing repeaters. I made a repeater out of mobiles and then sold it on Ebay, but left the antenna up just in case I wanted to put another repeater up one day. This antenna was at 30 feet and not connected to anything for the better part of a year when I got a knock on the door. It was a neighbor complaining that he was getting interference on his TV. I told him that it wasn't me and invited him in to see the coax that wasn't connected to anything. I offered to come to his house to investigate what could be causing his issue, but he refused. I guess he was embarrassed when he realized that it wasn't me. I never heard from him again.

That was years ago and now I have a small antenna farm in the back yard. I routinely ask my neighbors if they are having any issues and if they are to please let me know. I agree with the other posters that your neighbor should be taking the bull by the horns and squashing the interference without making you do anything other than letting your neighbor know when the problem is gone.
 

prcguy

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So Cal - Richardson, TX - Tewksbury, MA
I had the same problem when I was much younger with an antenna on a mast that sat disconnected for months and a neighbor came to my door several times and claimed "that" antenna is wreaking his TV even though I showed him there was not even a cable connected to it. That didn't matter since that antenna had to come down in his mind.

Now I have what looks like a repeater site in the middle of a dense residential neighborhood and often run full legal limit 80 through 10m plus lots of VHF/UHF stuff. I suspect I may occasionally cause interference but nobody ever comes to my door or lets me know there is a problem. Maybe its because early on when I was installing some of the antennas and neighbors asked what they were for, I replied "its for the Embassy". I think my neighbors are just too afraid to complain.

Post 4 in this thread has a very old picture of my tower. https://forums.radioreference.com/pictures-your-shack-mobile-setup/187883-lets-see-antennas-too.html
prcguy


I put up an antenna for a UHF FM repeater once when I was starting out in installing repeaters. I made a repeater out of mobiles and then sold it on Ebay, but left the antenna up just in case I wanted to put another repeater up one day. This antenna was at 30 feet and not connected to anything for the better part of a year when I got a knock on the door. It was a neighbor complaining that he was getting interference on his TV. I told him that it wasn't me and invited him in to see the coax that wasn't connected to anything. I offered to come to his house to investigate what could be causing his issue, but he refused. I guess he was embarrassed when he realized that it wasn't me. I never heard from him again.

That was years ago and now I have a small antenna farm in the back yard. I routinely ask my neighbors if they are having any issues and if they are to please let me know. I agree with the other posters that your neighbor should be taking the bull by the horns and squashing the interference without making you do anything other than letting your neighbor know when the problem is gone.
 
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SCPD

QRT
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Virginia
Your comments 161, brought a quiet smile to my face, for I think-- rather remotely, that your neighbor might have been on to something-- had the circumstances been a bit different.... well-- a lot different.
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But here goes---- Another Coyote Story-- :)
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Scene: We had placed this radar on a tall hill overlooking an Alaskan villiage. The intention was run it unobtrusively for a test period... but that never happen'd-- the unobtrusive part, that is.
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Action!: From the moment that installation went hot, the complaint line lit up.
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Story Line: We were knocking everything RF related off the charts.... not just the local TV and FM translators, but the cellular system, business and public service radios- probably even the poor CB'ers were suffering.
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This radar unit was a blow torch !, but not unlike many that we'd test'd side by side with civilian systems in similar settings.
Needless to say, if for no other reason than a serious PR issue- the plug was instantly pull'd.
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We asked the towne authorities for a meeting to discuss our (mutual?) problem- and also plead'd that at that meeting all the pitchforks, torches, their big caldron of tar and the bags of feathers-- all be left outside.)
We considered moving the radar to another location (as in; to another, innocent, unsuspecting towne)- but the expenses already involved, and the uncertainty that things would be different made exploring the problem at least worth an investigation first.
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We got an agreement from the towne to stage limited tests, as in during the wee hours of the morning when polite society would be fast asleep and our public nuisance would be at a minimum (from 3 to 4 AM, groan...)
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As soon as the unit went hot, the interference return'd. This radar was no shrinking violet-- it's peak pulse energy was in the Zigga Watts-- being in its direct beam path and it would literally cook a steak-- but nothing was in that path (I'm very, VERY careful there.)
However, an interesting phenomenon was noticed almost at once. As the antenna swung on its axis, the interference varied in signal strength, naturally, as would be expect of things falling within its path. But it did not peak where expected- that is- over the towne--
It peaked when the antenna faced a neighboring hill side- bare of anything.... anything except a telephone tower with those neat, big microwave horns of yester-year.
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Hmmmmmmmmm
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The next day I call'd the tel-comm guys and asked them about that tower.
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"That was taken out of service years ago...its completely dark" they said.
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"Can I take a look at it?" I ask'd
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............................and was given the keys......
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Going into closed up installations is always a creepy experience for me- especially in the far North Country where who-knows-what may have decided that big concrete block building is a great place to winter-over.
But enter we did- and it was like a time capsule- every piece of equipment still in place, as if expecting to be turn'd on tomorrow.
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One of the engineers, looking around at the racks of equipment, and the waveguides entering the building said:
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"Lauri, I have a hunch"
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.... and taking a pair of vice grips, she began to disconnect the waveguides from the racks of equipment.
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"Someone is going to be P**s'd with you!".... I said, but I understood immediately what she sensed.
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Every antenna was disconnected-
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"Now lets run another test" .... she said.
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_________________________________________
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Scene: It was 3 AM---- radar at full power------- and all traces of the interference--- Gone.
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*****(Laughing)--- Quiz time. What hunch did my friend and colleague have seeing those old horn antennas............. ? *****
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____________________________________________________
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Anyway, back to your neighbor 161, and the "inactive (?)" antenna??... in that case a far, far stretch.
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But it brought a wistful smile of remembrance ..... :)
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.................................CF
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smog515

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Forest Park,, GA
High Pass filter

Do you hear your neighbors voice very clearly or is it a garbled spacey sounding voice that you can't quite make out? If you hear it clearly then your neighbor is probably using AM mode which is most common to CB radio and a few discreet amateur frequencies in the 80m and 40m band. Single Side Band or SSB is the most common voice mode used for HF amateur radio and you can't make out the words when it interferes with stuff.

Since CB is way more common than the very small number of amateur operators using AM mode, I would suspect your neighbor is causing interference with a CB. A stock CB can rarely cause a problem but when used with an illegal amplifier or a higher power amateur radio is used illegally on CB it can easily come through older analog TVs. Your neighbor might not be telling the complete truth about what he is using and he may be operating illegally.

Ask your neighbor what frequency he was using at the time you had interference. Ask what kind of license he has and get the call sign. When confronting CBrs in the past I've heard them boast about being "fully FCC licensed" but a legal amateur operator will usually say I have an amateur radio license, so your neighbors statement about being licensed is a little odd and possibly misleading.

Does he have more than one antenna? Can you take a picture and post it here?

----------------------------------------------------------

I only hear very loud interference with a voice, but I can't make out what he's saying. I just figured out it was a call out because the sound was repetitive. Sounds like the SSB situation you mention above. He says he's broadcasting at 25 MHz. He gave me a copy of his FCC license. He was previously licensed with operator privileges as a Technician, now is licensed with General Operator privileges. His call sign/number is KM4VDZ if that means anything to you. He has one 30 ft antenna (that's an estimate, I don't know the actual feet - looks like twice as high as his house.) Thank you for explaining this in sort of a language that I understand. It's going to take me a while to digest some of the other posts.
 

peterwo2e

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Messages
115
tv rf is so tricky to locate sometimes is almost impossible. if its not interfering with the picture and you just hear him the rf is getting into the speaker section. is time consuming, if he using 10, 15,20,40,and 80 mhz
you have to narrow it down to witch band is the one that is causing the most if not all the problems. 28mhz is notorious for receiving radio rf, 50mhz is right on the old TV spectrum before they went digital. high pass and low pass filters hardly if ever work. when you get the strong interference quickly let him know so he could narrow it down to a certain band. back in the 80s i was strictly confine to 15 meters for over 10 years . that was the only band that my neighbors would not get any RFI. good luck.
 

SCPD

QRT
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Location
Virginia
I fear that Smog maybe up against an issue that the interferring KM4 fellow may not be able (or willing) to correct.
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Years ago I remember radio clubs and organizations had TVI Committees... are they still around? The ARRL ?
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I wouldn't know how to direct Smog to their assistance... maybe some one could (?)
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Smog, this guy has an obligation to you -by virtual of that FCC license- to fix things. If things get ugly, remind him of this section of the FCC rules--- and that you can 'drop a dime' on him.

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§97.121 Restricted operation.

(a) If the operation of an amateur station causes general interference to the reception of transmissions from stations operating in the domestic broadcast service when receivers of good engineering design, including adequate selectivity characteristics, are used to receive such transmissions, and this fact is made known to the amateur station licensee, the amateur station shall not be operated during the hours from 8 p.m. to 10:30 p.m., local time, and on Sunday for the additional period from 10:30 a.m. until 1 p.m., local time, upon the frequency or frequencies used when the interference is created.

(b) In general, such steps as may be necessary to minimize interference to stations operating in other services may be required after investigation by the FCC.
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I sincerely hope it doesn't come to that
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.............CF
 

wrath

Member
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Dec 18, 2005
Messages
465
I have a pair of Samsung 9000 series 55 " ers that when I get on 6 they reset themselves into store demo mode, Its crazy how sensitive they are to RF.

Sent from my SM-T810 using Tapatalk
 

lmrtek

Active Member
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Messages
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your description sounds like its coming in via the speaker or speaker wires.
Most TVs have a rear jack for audio out

try a external speaker system
 

prcguy

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Looks like your neighbor was a Technician class and upgraded to General effective September 26 of this year. Is that about when your interference showed up?

I suspect he got a new HF radio and maybe an amplifier to celebrate his upgrade, which would explain the interference. From your new description of the interference it does sound like he is using SSB mode which is the most common mode used for HF.

At this point I would suggest you print out the FCC Part 97.121 info that CF posted and show it to your neighbor, asking for his assistance in identifying and fixing the interference. That can easily be done in a friendly manner if you ask him how "you guys" can find a way to keep ham radio transmissions out of the TV, without making it sound too personal or offensive to him.

If he refuses to help, then tell him he is now officially notified his amateur radio station is causing interference to a broadcast service and you would like him to abide by FCC part 97.121 and the resulting limited times he can operate, otherwise you will escalate this to the FCC. Then if he helps you fix the problem he will be relieved from the FCC part 97.121 obligation. I also see your neighbor is a member of this amateur radio net: https://www.qrz.com/db/KP4NET
If he was causing me interference and didn't lift a finger to help, I would not hesitate to contact the net, tell them one of their

If it has to escalate I can give you tips on sending FCC complants, which is basically clogging their email and fax every day and several times a day wiht your complaint and it will take a good two weeks to hear from them, but they will respond.
prcguy
 
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