First AM RFI problem

[K5UJ]

Well on Saturday I had my first RFI complaint since I started operating mostly AM.  I had signed out of the Classic Radio Net a few minutes earlier when I heard knocking on my front door.  One of my neighbors was there.  They have lived next door since before I moved in, in 1994, and are my best neighbors--the husband offered to help me put up my 75 m. vertical--this time the wife graciously and apologetically explained that they had determined that my transmissions were knocking their cable modem off-line.  This was Comcast.  TV was fine, but they could hear me on their land line which was how they discovered that it was me getting into the modem (I was running 300 w.).  She emphasized that she didn't want me to curtail my operating (we are so nice in the midwest thank heavens) but wondered if there was anything I could do.  I told her I'd be happy to come over and take a look at the situation and try to fix the problem.

The next day, yesterday, I went over there in the afternoon with my bag of tricks.  I had learned that I should advise them to call Comcast and get a tech. to come out as well.  Apparently Comcast has modems they can use for people near broadcast stations.  In my bag I had electrical tape, scissors, a flashlight, dikes, cable ties, five 7" by 1/2 inch Amidon ferrite rods (mix 31), a few dozen mix 31 snap on beads of various sizes, some large 2 inch by 2 inch Fair-Rite cores I got at a flea market, a 3 prong extension cord, and a long cat-5 cable.   The modem was running into a WiFi box.  Fortunately it was powered by a linear supply wall wart.  I took out their cat-5 cable and put mine in with six mix 31 split cores on it each with the cable looped through it 3 times.  I put the wall wart on the extension cord and wrapped the 12 v. line 20-30 times around one of the rods and wrapped it with tape.  The rest of the 12 v. line I wrapped in a mix 31 core.  I ran the cable coax through the two big cores about 3 times each and put everything back together and went back to the shack thinking that if this didn't work I'd be out of ideas.   I called them up and she went to the modem and I  hit the switch on 3870 and without even modulating the carrier she said the modem went out.  I cut the carrier and she restarted the modem and I keyed the rig on low power and turned up the drive slowly.  When it got to around 100 - 150 w. it killed the modem.  Damn. 

I began to daydream again about life in the country which is where all AMers seem to wind up.   A friend advised me to have them disconnect the cat-5 cable and see if that made a difference.  Well duh, of course--basic troubleshooting.  Feeling like a novice all over again I called them back and we tried the test and the modem kicked off with the cat-5 cable disconnected, so we knew the problem had to be common mode on the coax or the 12 v. line.  I bet on the coax. 

I had been testing all the ferrite I had used with my Xl meter on my swr analyzer to make sure I used ferrite material types that had some decent Xl on 75 and 160, at least 500 ohms on a wire looped through the core 3 times. Everything I used was at least that but mostly off the charts, over 1500 ohms.  I had a bunch of big material J doughnuts I had gotten from Amidon a few years ago but they measured real low so I didn't use them.  Now I was willing to try anything.  I went back over there and put 2 or 3 of the J doughnuts on the coax.  They were big enough so I could get about 6 loops of coax through each one.   I also gave them a couple of ICE filters for the land line.

I went back to the shack and we repeated the routine.  This time to my amazement, the modem stayed on-line, even with me hanging a 300 w. carrier for 10 minutes and occasionally modulating it to identify, give my QTH and other blather to get the p.e.p. up there but it stayed on-line the whole time.   this resulted in a pleasant QSO with W9UB and W9AD who heard the carrier.   Later I checked the J doughnut on the Xl meter and found with 6 to 8 loops through the core it gets up there around 500 to 600 ohms on 75 meters and increases down into the medium waves as it should according to the specs from Amidon, so I should be okay on 160 too. 

The Comcast guy is coming out on Saturday morning so I'll go over there and see what he does.  Then I'll have the neighbors over to see the station.  It all turned out real well because even if the Comcast guy screws everything up, I can put it back like it was.   It's nice to be able to fire up the rig and operate whenever I want to and not wonder if the neighbors are getting any RFI.  Turns out that DTV and cell phones have their positive sides hi hi.

Rob K5UJ

[KX5JT]

Bravo!!! I love a good ending!

[WA1GFZ]

J material makes a bitchen common mode choke all the way down to 10 KHz and into the low end of the HF band. ui=5000 material is like a Mexican jumping bean. I designed a custom part and had it produced for a work project.

[ka3zlr]

It's always great when you can go to the problem an make modifications or repairs whatever is needed an maintain a good friendship..Excellent..Very Good.

73
Jack.

[K5UJ]

Thanks you guys; I'll have to remember that about J material.

It worked out great and my neighbors are wonderful.  I still think about having a few acres in the country though.  Land in northern IL is so darn expensive.  You have to get way out west, at least 100 miles west of Chicago, before you can afford to purchase enough space with money from the sale of your current property, to make the move worthwhile.  I looked around a few years ago and was surprised and disappointed to find that I wouldn't be able to gain anything unless I went way out there, too far from my job. 

R.

[WD5JKO]

Rob,

  It is good that you were able to solve this issue. Many of us run into an irate person that cannot possibly understand that the RFI issue is due to their equipment acting as a radio receiver when it is not supposed to. When I detect this attitude, I refer them to part 15 rules that apply to home consumer electronics, and then I give them the FCC phone number. At that point I usually decouple myself from the issue by staying low (not turn on my amplifier) for a while until they cool off.

  Over the years it has been rare for a neighbor of mine experiencing RFI/TVI to open their door to let me look at the situation. They simply feel that the problem is mine, and that is the end of the discussion.
  Also keep in mind that many items such as amplified speakers will pick up AM signals when turned off and even with the speaker wires disconnected. The AM ham voice will be broadcasted through the speaker. Not an easy fix here.

73,
Jim
WD5JKO

[The Slab Bacon]

I got the best one I heard yet from my wife this past saturday. She was sitting on the front porch talking to the neighbors while I was on the "Whatz fah dinnah" / "heartbreak of psoriasis" net on 3.733. She came running down the stairs laughing that they could hear me coming out of the rainspouts!   

Keeping in mind, I have had complaints of coming out of everything from CFL lamps to toasters to garbage disposals.   

The following day it had stopped. This was after several days of rain. I just figured it was a corroded joint in the spout or gutter acting like a rectifier. It hasnt happened again since.

                                                    the Slab Bacon       

[W1AEX]

Yup, audio rectification can certainly make life interesting. When my daughter was 3 or 4 years old she started saying "Yeaaaaaaaaaaaahhhhhhh - a - low" over and over again at the breakfast table one morning. My wife asked her where she had heard this strange word and she reported that my voice was coming out of the baseboard heater when she woke up the night before. The little fins along the copper pipe in the baseboard heater were doing a pretty good job of rectifying my 160 meter signal.

It might be a good idea to keep a stack of QSL cards near your door to hand out to anyone who comes knocking to give you an unsolicited signal report. Make sure they critique the audio too, since they are going to have to listen to you until they fix their appliances!

[K5UJ]

Haven't had the rusty fence rectification experience yet; thought you had to be WLW for that    but a few years ago I had the computer speaker experience and the diode rectification driving speakers even when the stereo was turned off. 

I try to make a point of politely explaining that inferior consumer electronics quality is usually the culprit but if folks are nice I try to do something while making sure they know the real responsibility lies with the ISP/cable company/phone company etc.  If they're really argumentative I think I'd simply tell them we can discuss this but only after they've cooled off and end the conversation. 

That's too bad people complain but then don't allow you to have access to their widgets to see what's wrong.  I would expect that if the ham were the one going to them about QRM to his receiver from one of their gadgets, which is why I don't even bother to contact people about that; I just try to null out the QRM with a phase canceling box which I've had pretty good luck with.

[W9GT]

I try to make a point of politely explaining that inferior consumer electronics quality is usually the culprit but if folks are nice I try to do something while making sure they know the real responsibility lies with the ISP/cable company/phone company etc.  If they're really argumentative I think I'd simply tell them we can discuss this but only after they've cooled off and end the conversation. 

That's too bad people complain but then don't allow you to have access to their widgets to see what's wrong.  I would expect that if the ham were the one going to them about QRM to his receiver from one of their gadgets, which is why I don't even bother to contact people about that; I just try to null out the QRM with a phase canceling box which I've had pretty good luck with.

You have to be careful in today's litigious society working on or modifying anyone's equipment.  If you screwed something up, they could sue you.  Even if you manage to solve the RFI problem, they could still decide that they want to cause you problems.  I, too appreciate neighbors with a pleasant attitude and try to help them, however, some people just want to crab at you and blame you for problems with their inferior equipment.  I guess you have to look at it from their perspective, if you weren't there and on the air, they wouldn't have a problem.    The place out in the country is still the ideal situation.

I received a phone call a few years ago from a lady who lives about a half mile away from me.  She was very clever and industrious and looked up my call sign on the internet, found my name and then looked me up in the phone book.  She was very pleasant and asked me if I was the amateur radio operator who was using the "Old Federal Transmitter".  I was kind of startled by this reference...but I replied er....yes, how did you know about that?  She then explained that she had heard me regularly on Saturday mornings on her telephone and I always referred to my transmitter as the "Old Federal".  She went on to explain that they had one telephone that apparently was acting as a radio receiver and she could hear my transmissions quite plainly when I was on the air.  She asked me if there was any way that she could eliminate the problem.  I was quite appreciative of her polite and pleasant manner and I gave her several recommendations for in-line phone filters as well as suggestions for replacing the particular phone that was causing the difficulty.  She called again a couple of weeks later, thanked me for my suggestions and said that she had purchased a new phone and that had completely eliminated the problem.  She also said that she was going to purchase a few of the phone line RFI filters to plug-in into the cords of all her phones, just to be safe.  Wow!  That was a positive experience of successful remote troubleshooting with very gratifying results!  Unfortunately, many complaints that we might receive are at the opposite end of the scale with reference to cooperative attitude.

73,  Jack, W9GT

[The Slab Bacon]

Jack,
       You were quite lucky with that one. I have found that living in a close suburban community and running high power has its moments! Most of my neighbors that have complained nicely have gotten common mode chokes for their cable and or phone lines from me at no charge to them. (I let them install them) and all has been well. But...................

One neighbor in particular has become a pretty bad situation. I offered him filters several years ago, and he told me that he "didnt want to be bothered". I then politely instructed him to contact the phone company, Comcast and the FCC for other alternatives. The situation has now come to the proverbial head. he has called Zoning on me 3 times now and is trying to start rumors and trouble for my wife and I in the neighborhood. The more he trys, the more the others play him off.
It has become an obsession for him now. Especially after I told him to go and pound sand up his a$$ in front of the whole neighborhood. One night a few weeks ago he cussed my wife out and belittled her to the point of tears. I tore out of the house and went after him. He ran in and locked all of his doors.

I stayed out on the porch until he tryed to sneak out without being noticed
(by me) and let him have it with both proverbial barrels. I cused him up one side of the street and down the other. (with all of the other neighbors watching) I christened him with his new name - "Johnnie No-Balls" since he could cuss out a woman, but didnt have the guts to face her husband. Now many of the other neighbors are calling him that as well. It took everything I had that evening not to break him into little pieces. I now run as much power as I can just to piss him off more.

So, Jack,
            You were lucky and had a pleasent experience. Some of us werent that lucky

                                                  The Slab Bacon 

[WA3VJB]

1. For entertainment, don't watch TV, go set off Frank.

2. Watch out, Frank's wife Carol is actually the tougher one.

[k4kyv]

The lady who lives across the road complained a few years ago that I was getting into her telephone.  I had someone transmit and run a test while I went over and checked it out.  The voice from the radio was barely audible, but if you listened carefully you could make out what the speaker was saying.

Then she explained that hearing my voice in the background of her phone wasn't her concern.  She was absolutely positive, and there was no convincing her otherwise, that if she was able to hear my radio conversations over her phone, that I would likewise be able to eavesdrop on her phone conversations using my radio, and she was pissed off that I was invading her privacy.

[Steve - WB3HUZ]

I had the same problem years ago at a previous QTH. Not much you can say. I tried but I don't think it sunk in.

The lady who lives across the road complained a few years ago that I was getting into her telephone.  I had someone transmit and run a test while I went over and checked it out.  The voice from the radio was barely audible, but if you listened carefully you could make out what the speaker was saying.

Then she explained that hearing my voice in the background of her phone wasn't her concern.  She was absolutely positive, and there was no convincing her otherwise, that if she was able to hear my radio conversations over her phone, that I would likewise be able to eavesdrop on her phone conversations using my radio, and she was pissed off that I was invading her privacy.

[K1JJ]

Back in 1975 I lived in a house in Newington, CT with four other dudes.  It was a fairly populated area with a big church about a block away.

I was using a 75M dipole at about 50' and ran four homebrew 4-400A's in GG with 4KV - using a hi-fi AM RF driver at the time.  It was a big maul for the time.

Anyway, one Sunday morning there was a wild gathering on 3885 AM with the regulars. Mostly WA1's.  We were all in our 20's and crazy. The session went on for a few hours and I did my part to keep it rowdy.  Later in the day I got a knock on the door.  There was a priest standing there with a mad look on his face.  It seems I was getting into the church PA system BIG-TIME during the morning masses.  He repeated some of the things that went on.  I cuda crawled between the floorboards when he told me.   I wish I had a video of the whole session in church from beginning to end. The look on the congregation's faces... Oh, the humanity!...

T

[K5UJ]

>>>I guess you have to look at it from their perspective, if you weren't there and on the air, they wouldn't have a problem.  Roll Eyes  The place out in the country is still the ideal situation.<<<

Jack, if I get the "my problem will go away if you stay off the air" line, I plan to say "my problem will go away if you never turn on your tv."  Makes about as much sense doesn't it.

The thing about moving to the country is that around here it seems to only buy you time.  I've talked to folks who moved out to a cornfield and thought they had found heaven.  After a few years the farmer across the street got talked to by a developer and came away with $$$ in his eyes.  Ditto for the farmer with the cornfield next door.  After a few years their patch of heaven had one of those "suburban ghettos" cookie cutter houses across the street and next door a Supermarket.  I mean, to have any peace and quiet guarantees you have to move next to a superfund site, or maybe the Yukon. 

Slab,  man that stinks with your one bad apple neighbor.  Hope he moves away.

Rob K5UJ

[K5UJ]

Back in 1975 I lived in a house in Newington, CT with four other dudes.  It was a fairly populated area with a big church about a block away.

I was using a 75M dipole at about 50' and ran four homebrew 4-400A's in GG with 4KV - using a hi-fi AM RF driver at the time.  It was a big maul for the time.

Anyway, one Sunday morning there was a wild gathering on 3885 AM with the regulars. Mostly WA1's.  We were all in our 20's and crazy. The session went on for a few hours and I did my part to keep it rowdy.  Later in the day I got a knock on the door.  There was a priest standing there with a mad look on his face.  It seems I was getting into the church PA system BIG-TIME during the morning masses.  He repeated some of the things that went on.  I cuda crawled between the floorboards when he told me.   I wish I had a video of the whole session in church from beginning to end. The look on the congregation's faces... Oh, the humanity!...

T

Tom, the only thing worse would have been if the W1AW voice bulletins had been on AM back then 

At least no one dozed off during mass.

One thing my neighbor mentioned was that she could never hear the other side of the radio conversations; only me.  I of course explained that the other stations were far away but if she could have heard them, wow, that would have been some telephone receiver!

Rob

[WD5JKO]

My most memorable TVI experience was in about 1983 and the person experiencing the TVI was next door. I went over there, and a simple portable TV with rabbit ears was having problems with my AM KW rig (850w carrier output). Boy I miss the old 1KW DC input days.

I went back home and keyed my transmitter, and then looked at the TV. It had some interference, but not that bad really. Now I was in my 20's, and my neighbor was in her 40's, and she was wearing just a bathrobe. I picked up by peripheral vision that the bathrobe belt was loosening, and the whole situation was a looking like a set up. Now I was not attached to anyone, and it had been a while for me, and from what I could tell, things could have happened. Then I remembered that transmitter running key down at 1KW input. I decided to save my finals and went home to shut off the rig.

I never heard from that lady again. true story. 

Jim,
WD5JKO

[KX5JT]

My most memorable TVI experience was in about 1983 and the person experiencing the TVI was next door................

...............Now I was in my 20's, and my neighbor was in her 40's, and she was wearing just a bathrobe. I picked up by peripheral vision that the bathrobe belt was loosening, and the whole situation was a looking like a set up. Now I was not attached to anyone, and it had been a while for me, and from what I could tell, things could have happened. Then I remembered that transmitter running key down at 1KW input. I decided to save my finals and went home to shut off the rig.

I never heard from that lady again. true story. 

Jim,
WD5JKO

*sigh*  I love a good ending...

[k4kyv]

Tom, the only thing worse would have been if the W1AW voice bulletins had been on AM back then 

 I can  recall well into the 1960's that ARRL-appointed OBS stations could regularly be heard relaying W1AW bulletins on 75m using AM phone. I haven't heard any of those official bulletin transmissions on HF for years other than from W1AW, but now, with the internet, there is less need for bulletin transmissions even from W1AW.

I recall from reading through my pre-WW2 QST collection that OBS appointees used to be called "Official Broadcast Stations." ARRL must have become paranoid in later years regarding the FCC prohibition against "broadcasting", and changed the designation "broadcast" to "bulletin", even though there is nothing in §97.111 that restricts or even mentions what name amateur stations that transmit information bulletins should be called.

I am curious if there are still any ARRL Official Bulletin Stations that actively transmit information bulletins on HF phone. Of course, if they used AM, there  would still be the danger that the operator would fall asleep and leave the dead carrier running and toast the transmitter.

[N3DRB The Derb]

I have heard of the converse happening, that hams have been contacted after a successful interference intervention with neighbors who wanted to know where they could buy a receiver to hear the goings on!

The more I think about it, I'm pretty sure it was Ozona Bob who told the story but I cant remember if it was about himself or another ham.

[N3DRB The Derb]

Don, I think those guys are all CW mavens now - the kind that does 40 wpm before the morning coffee. They just love passing the ARRL traffic hither and yonder, which is cool with me.  They got the thangs to do what they enjoy same as me.

[K5UJ]

I used to be an OBS back in the 70s, but in my case it meant transmitting the ARRL bulletins on cw during the Mississippi Traffic Net.  I have no idea now what the qualification requirements were to be an OBS but they must have been minimal for cw as all I had back then was a T-60, HA5 VFO, general cov. rx and a random end fed wire antenna.  I think I was also an Official Relay Station but I think any ham who regularly participated in traffic nets got that.

I once got into the computer speakers of a neighbor who was renting a house next to mine, and he wound up becoming a ham and moving away, which was a good thing in addition to becoming a ham, since two hams on HF next door to each other is not good. 

R.

[The Slab Bacon]

My most memorable TVI experience was in about 1983 and the person experiencing the TVI was next door. I went over there, and a simple portable TV with rabbit ears was having problems with my AM KW rig (850w carrier output). Boy I miss the old 1KW DC input days.

I went back home and keyed my transmitter, and then looked at the TV. It had some interference, but not that bad really. Now I was in my 20's, and my neighbor was in her 40's, and she was wearing just a bathrobe. I picked up by peripheral vision that the bathrobe belt was loosening, and the whole situation was a looking like a set up. Now I was not attached to anyone, and it had been a while for me, and from what I could tell, things could have happened. Then I remembered that transmitter running key down at 1KW input. I decided to save my finals and went home to shut off the rig.

I never heard from that lady again. true story. 

Jim,
WD5JKO

Like I said before: SOME GUYS HAVE ALL OF THE LUCK!!             

[ka3zlr]

Well then Move Damit...LOL....Diana an I lived in 5 places till we found the one we wanted, and as it ends up we're on a Farm it's nice quiet lotsa space...but you still have RFI out here too. some o them old farmers TV's and phones were older when I got here,.some of them ole farts didn't buy nothen new....6 meter was the worst years ago somebody always knocking on the door.

NOW that FIOS is moving in ya man we can dig it... The kids Taking over the Farms now are Hip an like HD AND Cell Phones...Yeeaaaa.... ....Get-R-Done...lol..

73
Jack.