Posted: 7/6/2011 8:07:26 AM EDT
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well, figured it'd be a problem but, didn't think it would be when running just 100w Neighbor came by today while I was cutting the lawn saying that he's getting interference on his cordless phone.... anyone have any links to where I can start taking a look at the problem? also, any tips for what I'm doing wrong. thanks
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| You may not be doing anything wrong. Alot of consumer electronics have poor or no filtering in them. As long as your equipment is tuned properly and grounded, the problem is his. You can offer assistance to help resolve the interference, but don't take all the burden upon yourself. Ferrite beads on his phone line or power cord to the phone may help...maybe not. |
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Quoted: You may not be doing anything wrong. Alot of consumer electronics have poor or no filtering in them. As long as your equipment is tuned properly and grounded, the problem is his. You can offer assistance to help resolve the interference, but don't take all the burden upon yourself. Ferrite beads on his phone line or power cord to the phone may help...maybe not. I'm going to assume that's my first problem - no grounding I'm three floors (and 30 or so feet) up.... any way to do that without making a resonate length?
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Kenwood ts440s to 6' of rg8x... to an mfj tuner then 6' more of rg8x...to an mfj passthrough... to 100' of rg213u to a 1:1 baling and an 80/40/20/10 fan dipole.
Station is 30 or so feet up... (about 30' to the window and there is a small roof sticking out above the first floor) Posted Via AR15.Com Mobile |
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Ground your equipment to the electrical ground in the house wiring. I didn't mean an antenna ground. Keep the ground run as short as possible. Flat copper strips are the preferred material for grounding but wire will work in a pinch. Best way to do this? Run some ground up from the pannel or? I'm up in the attic, everything is a long run Posted Via AR15.Com Mobile |
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Ya...as KB said... Ground your radio and tuner. Best would be to a ground rod but as this looks to be somewhat a pita to do, grounding everything to the houses' electrical ground should suffice. That said, lets hope the house ground is actually grounded...otherwise you may cause interference inside your home...lol.
If it were me I would still try to use a separate ground. 8ft ground rod and enough copper braid to reach it. |
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Ya...as KB said... Ground your radio and tuner. Best would be to a ground rod but as this looks to be somewhat a pita to do, grounding everything to the houses' electrical ground should suffice. That said, lets hope the house ground is actually grounded...otherwise you may cause interference inside your home...lol. If it were me I would still try to use a separate ground. 8ft ground rod and enough copper braid to reach it. Will 30' of copper braid be a problem? I'm going to assume that my house grounding isnt there... 1929 house that still has knob &tube wiring in it Also... will driving the ground in a hill be a problem... that side of the house is a 5 of so foot hill... Posted Via AR15.Com Mobile |
| Run a wire (strip) to each piece of equipment and then to the ground terminal on your 110v outlet. This isn't optimum, but may help. Remember, most consumer electronics are CHEAP and the reason they are is the mfg has cut corners. Filtering against RFI is a cost factor so many mfg's skip it. The figure they won't have many complaints and they are mostly right. But don't let the neighbor bully you into fixing his cheap phone. Tell him you are licensed and are following all the rules. The problem is his equipment and you will try to help resolve it, but can't make any guarentees. Ferrite beads on his phone are the first thing to try. |
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legally it isn't your problem. ground yourself properly, make sure you are in good operating condition. tell them you adjusted your station to try and minimize interference. then, don't transmit for a few weeks, see if they come back saying there is interference, if they do, then you can say, "well its not me, I haven't turned my radio on in weeks" if they don't and you start to run again and they come back and report problems, tell them they need to buy RF filters, and that it may or may not work. they should have them at home improvement stores, but don't tell them exactly what to buy, because if it doesn't work they may come after you. if the filters don't work tell them to buy new phones in a different spectrum. your involvement is up to you. if you feel bad and they are a nice old couple who bake you pies and watch your dog on weekends, go pick up the filters and try what you can to make it right. it makes you and the community look better when you help try to solve the problem. but, if they are the neighbors every one hates who call the cops every time your dog barks, you can just tell them what to do and leave them to figure it out on their own. |
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Look at this:
Description: Resonates a random length wire counterpoise and produces a tuned artificial RF ground or places a far away RF ground at the station equipment by tuning out ground lead reactance.
MFJ-931 |
| One little tip. Ask when does the neighbor have interference? When we put up dads tower the neighbor came over saying he was getting tons of interference since we put the tower up. There was not a single antenna on the tower much less feedline ran up the tower. He saw tower and assumed that we were causing his problems. |
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I am also on a 3rd story, I do not run a ground.
I have been told by many people that have run apartment stations, or upper floor, not to tie into the AC ground. The fact that the ground is still going to run to the earth you will have RF on the ground wires. I was always told the it is better to have no ground. (If you are not having any hot spots) Now the people here have operated much longer than me and are more knowledgeable than me on this. But for the sake of getting as much info as possible I will post a couple of solutions I have researched but have not done. Those that have more experience on this may weigh in on this, because we all know that the Internet is full of bad info. I have read that you can use some metal screen under the the table with a short lead of wire (less than 8 feet) to tie all of the equipment into to, I am guessing the idea was to spread it out over an area without having a wire at a resonant length. I have also read about many apartment hams with RF hot spots that used a multiple short wire ground system spread out under the carpet, or the plastic chair platforms that go under the desk. I have only had a problem on 15 meters, our cordless does not like it, and my XYL can hear me on the phone. It is my understanding that cordless phones are notorious for picking up RFI. So when she yells "I can hear you on the phone again" I tell her to let me know when she is done and switch to 20 meter. |
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Quoted: One little tip. Ask when does the neighbor have interference? When we put up dads tower the neighbor came over saying he was getting tons of interference since we put the tower up. There was not a single antenna on the tower much less feedline ran up the tower. He saw tower and assumed that we were causing his problems. I have read and heard that its best to put up a tower and let it sit, just to see who complained about interference, document their complaints, inform them of your not transmitting, and then install your antennas and transmit, that way if they keep coming back you have proof of problems before your station was operational. some people assume its you, and some people just want your tower gone so they make up problems and complain so their view isn't "ruined"
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More than likely there is nothing you are doing at your station that is creating the problem, other than you are transmitting.
The vast majority of current consumer electronics has no RFI rejection at all. Probably all that is needed is some ferrites on the incoming telephone line to the cordless base, and possibly the power. |
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Wife also said she heard interference when she was on the phone (standing just about under the damn thing) so I'll assume it's not made up. I'm not getting any hotspots on the rig, tuner, mic or anywhere else in the shack - I was trying to see if I could get by without grounding since I'm on the third floor and haven't found a decent solution - the MFJ unit looks interesting though, one more thing for me to tune when I swap bands  I'll try putting the tuner and rig on the house ground and see if it takes care of it - if it does when the electrician comes to re-wire the house I'll have him run just a ground up from the box also. I would try pipes but they're on the other side of the attic - would radiator pipes work? I have some of those coming up but, they don't go to the ground. Next step is some ferrite beads for the phones (I assume they'll help for cordless and that the static is from overloading the lines themselves) or grounding down below the window. I'm going to get with him tonight and see if I can replicate what his wife heard - they're good people and I'd like to stay on good relations with em... I got lucky in the neighbor department plus, we just moved in... no need to not be as helpful as I can be living here less than three months. Thanks guys... any other tips throw them on out...
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ok, fucked with it a bit only 80m is a problem..... 40-10 couldn't hear anything (I was on the phone with the wife, standing on the patio almost under the antenna) 80m... I could hear it on my end in the phone also does that change anything? anything I should look at? oh also, grounded to the ground on the outlet - no dice... didn't help. |
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Quoted:
Quoted:
One little tip. Ask when does the neighbor have interference? When we put up dads tower the neighbor came over saying he was getting tons of interference since we put the tower up. There was not a single antenna on the tower much less feedline ran up the tower. He saw tower and assumed that we were causing his problems. I have read and heard that its best to put up a tower and let it sit, just to see who complained about interference, document their complaints, inform them of your not transmitting, and then install your antennas and transmit, that way if they keep coming back you have proof of problems before your station was operational. some people assume its you, and some people just want your tower gone so they make up problems and complain so their view isn't "ruined" Lot of this shit goin' around. Ya just go an' make friends with a good cop. "Jeez, Lady, Whaddya mean he was transmitting last night? I don't know how seein' as me and six other cops had ta wrestle him down and take him ta jail last night after he hospitalized 4 Penn State football players! Lady, ya don't wanna piss that guy off!!!" |
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are both your cordless phones on the same spectrum? 2.4GHz, 900MHz, 6.0GHz.... im not the smartest with this, and I may be completely wrong, but I wonder if its just with the wireless portion of the phone, and since its the specific band that it may be just interacting with where ever your phones are at. if thats the case, then new phones, if not and it is just getting in the phone lines then ferrite on the lines.
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Quoted: are both your cordless phones on the same spectrum? 2.4GHz, 900MHz, 6.0GHz.... im not the smartest with this, and I may be completely wrong, but I wonder if its just with the wireless portion of the phone, and since its the specific band that it may be just interacting with where ever your phones are at. if thats the case, then new phones, if not and it is just getting in the phone lines then ferrite on the lines. yes, both are 2.4 Ghz I may see if anyone has some on a different band and try that
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The interference isn't into the RF circuitry of the phones, it's going in via the phone line almost certainly. Almost all cordless phones are using some kind of digital spread spectrum system so interference to the RF circuitry would be almost unthinkable if the interference is anything remotely intelligible.
Grounding your radio from the third floor will be completely meaningless to this problem. The solution is to reduce the amount of RF that is being coupled into the phone wiring and into the phone base units. Most likely the easiest and simplest way to do that is put some ferrites on the phone cord right before they enter the phones. |
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Here are some links to help you:
A Ham's Guide to RFI. The EMI-RFI Page. The ARRL RFI Book (3rd Edition) |
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Ferrites on the phone line might be your friend. I'll bet your signal is coming in to the phone over the line. Probably would hear it on an old school hardwire phone.
I've used this stuff: http://www.ky-filters.com/ It worked. GL de W1EL |
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The interference isn't into the RF circuitry of the phones, it's going in via the phone line almost certainly. Almost all cordless phones are using some kind of digital spread spectrum system so interference to the RF circuitry would be almost unthinkable if the interference is anything remotely intelligible. Yeah, Nuc, is it intelligible on the phone, or does the phone just crap out? I can relate my own, similar experience: my 2.4GHz cordless system goes TU when running 40M. Same for a 5.8GHz system. Not intelligible so direct RF interference. I bought a top of the line Panasonic DECT system and no more problems. Buy your neighbor a new Panasonic DECT phone system. Heck, it's probably less expensive to do that than it is to pay for all the grounding and filtering, etc. And if it doesn't work you can return it to Staples or wherever you bough it 
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Quoted: The interference isn't into the RF circuitry of the phones, it's going in via the phone line almost certainly. Almost all cordless phones are using some kind of digital spread spectrum system so interference to the RF circuitry would be almost unthinkable if the interference is anything remotely intelligible. Grounding your radio from the third floor will be completely meaningless to this problem. The solution is to reduce the amount of RF that is being coupled into the phone wiring and into the phone base units. Most likely the easiest and simplest way to do that is put some ferrites on the phone cord right before they enter the phones. if it was getting in the phone lines why would it only be on one band? |
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Here is some more information on RFI.
http://www.hamuniverse.com/rfi.html |
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Quoted:
The interference isn't into the RF circuitry of the phones, it's going in via the phone line almost certainly. Almost all cordless phones are using some kind of digital spread spectrum system so interference to the RF circuitry would be almost unthinkable if the interference is anything remotely intelligible. Grounding your radio from the third floor will be completely meaningless to this problem. The solution is to reduce the amount of RF that is being coupled into the phone wiring and into the phone base units. Most likely the easiest and simplest way to do that is put some ferrites on the phone cord right before they enter the phones. if it was getting in the phone lines why would it only be on one band? Several reasons. Maybe there's a phone wire that is resonant on 80m in the neighbors house, maybe the phone has crap for filtering (which we all know it does) and can't reject the 80m signal. Ferrites ferrites ferrites...... |
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well, figured it'd be a problem but, didn't think it would be when running just 100w Neighbor came by today while I was cutting the lawn saying that he's getting interference on his cordless phone.... anyone have any links to where I can start taking a look at the problem? also, any tips for what I'm doing wrong. thanks SASE for 6 ounces and a decent envelope that will make the return trip for some RF phone filters. Just PM me for an address. These filters take out Broadcast Band radio very well, I'd guess they will work for Ham as well. |
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Quoted: Quoted: well, figured it'd be a problem but, didn't think it would be when running just 100w Neighbor came by today while I was cutting the lawn saying that he's getting interference on his cordless phone.... anyone have any links to where I can start taking a look at the problem? also, any tips for what I'm doing wrong. thanks SASE for 6 ounces and a decent envelope that will make the return trip for some RF phone filters. Just PM me for an address. These filters take out Broadcast Band radio very well, I'd guess they will work for Ham as well. PM sent |
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RFI can have some very strange causes.
The ARRL Interference Book I mentioned earlier had this case: A ham's garage door would open whenever he transmitted on 40 meters. The garage door opener operated on approximately the 2 meter band IIRC. No amount of filtering, etc on his transmitter helped... Then he took a tape measure and measured the length of the wire from the manual open/close button (just inside the door between the garage and kitchen) to the garage door motor. It was exactly 1/4 wavelength on 40 meters! THAT was how the signal was getting into the opener! |
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I get into a neighbor's alarm system. One that was already installed when he moved into the rental. There is no subscription paid, so the alarm co is not going to come out and troubleshoot.
I do not interfere with any of my other neighbors in any way, not on phone, stereo, TV, computers, nothing. Same with my own electronics in my own home. Just this one guy's crappy alarm system. You know, we had a problem with our wireless router, which would drop signal every time the phone rang. Did we blame the makers of any of that equipment? No, we bought some inline phone filters from Radio Shack. Plugged the filters into the phone jacks, and the phones into the filters. Problem solved. One guy had a neighbor complaining that she could hear him over her $19.95 Toys R Us baby monitor. He said, "Do you think the problem is in my thousands of dollars worth of FCC type approved radio gear, or your $20 toy store monitor. Oh, and I can hear you guys, too." It is not your responsibility to fix their crappy gear. If you are operating your equipment in the usual manner, and not trying to talk around the world on a CB with an illegal amp bought out of the back of a truck stop, then you are probably OK on your end. |
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I get into a neighbor's alarm system. One that was already installed when he moved into the rental. There is no subscription paid, so the alarm co is not going to come out and troubleshoot. On 40m my alarm starts acting up. On 20m my wife's dining room hutch the touch light turns itself on.
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I get into a neighbor's alarm system. One that was already installed when he moved into the rental. There is no subscription paid, so the alarm co is not going to come out and troubleshoot. On 40m my alarm starts acting up. On 20m my wife's dining room hutch the touch light turns itself on.
Same here. The wife was sleeping and I was playing radio when she stated yelling at me "The light in here is possessed!" |
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First try to nail down when exactly your neighbor is getting interference and see if it matches up with the times you are transmitting.
Kinda like when a new tower goes up but doesn't have any antennas yet and the neighbors start complaining about interference from it. Passive aggressive NIMBY bullshit.
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As y'all know all my antennas are in the attic. {Think when the whole project is complete I'll take a picture of it, put it on a QSL card, and call it "Toys In The Attic"} As such I've run into some interesting RF issues.
On Day 3 of HF transmitting I smoked both of the touch lamp controllers in the bedroom. Blamed the failures on the junky Chinese lamps I got at Lowes Depot. Got lamps with proper switches. When I transmit CW on any band, the ceiling speakers for the home theater system repeat. Wife has pretty much figured what my call is. Don't know what it is but as she put it "I hear a dah dit dah, some dits, some more dits, another dah and some more dits." Yup. That's my call. Seeing as the speakers are maybe 20 feet from the antenna it doesn't surprise me. Ferrite beads may fix it ... or not. When I transmit CW the undercounter lights at the operating station flicker just a bit. Doesn't bother me and gives the shack that Doc Frankenstein mad scientist air. New problem cropped up just last weekend. When transmitting on 6m SSB the wife can hear the audio on the FM radio. Heavily garbled but she could tell it was a voice transmission. Since 100 mhz is the 1st harmonic of 50 mhz I do have a real issue to contend with. Researching this one. As for the neighbors, no one has complained ... yet. |
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UPDATE: finally got around to working on this problem - as you know, I've just stayed off 80m since that was the only band giving any problems got down to radio shack today and picked up two wall mount phone jacks (the small square boxes), a 10' length of phone cord and some solder this is the result:  and the inside - ignore the horrible soldering job under the nasty electrical tape job  that small white box is the filter - one of these:   they are meant to be installed at the service point outside - well, my phone goes over our cable modem.... so I did the next best thing - in line filter after the modem before it goes to the house I made one for the neighbor also, I'll go over and give it to him, show him where to put it tonight when I see he gets home.... according to my wife the phone is dead quiet when I'm on 80m now so I assume they're working. DanishM1Garand - thanks again! I appreciate the help |