Shortwave antenna idea? Dormant phone line in the walls?

[paulhusker]

I'm very new to shortwave listening and antennas. I've experimented with the following idea a little. Here it is: I recently shut my land line phone service off in favor of just using my cell phone for local phone service. Since my phone line is dead, I wondered what kind of reception I could get. I clipped off the end of the wire that would go in the phone, cleared away the plastic covering and stuck it in the antenna jack on the shortwave radio. My little bit of experimenting found some stations to come in much clearer and stronger. I think a few stations, though, might not have been very receivable when using the phone lines in my wall for an antenna.

A question for any of you electronice whizzes: Is the phone line wiring in my walls a good source for any type of antenna--shortwave, AM, FM, or otherwise? Why or why not?

Thanks in advance for any of your help.

 

[loumaag]

Well obviously it will work as an antenna. How well depends on several things. Like what you are listening for, how much interference you will experience from electric wires that might be running adjacent to it, etc.

In any case, before you continue to use it as an antenna, go out to your residential telephone entry point box and unhook the house from the Telco connection. Although your phone might be shut off, that doesn't mean at some point you might not get 24v or more hitting the wire. Not a situation you really want.

 

[bsavery]

Like Lou said.... make certain you have totally disconnected it from the telephone network. :!:

Normal telephone lines have 48v DC on them at all times. That's what powers the phones. Ringing voltage is 90v AC.

Even though you have discontinued service, the line could still be connected at the Central Office to a port. If they happen to reprogram that port before moving the cross-connect to the new subscriber's line, POOF goes your radio! :shock:

Bob

 

[bwinking]

phoneline antenna

have used that before. works well on some bands.
some of the other things I've used are; metal water pipes, metal window screens, and frames, aluminum siding, gutters, downspouts , clothes lines, chain link and other metal fences. (almost any metal object that isn't connected to electricity,but skip the gas lines, for obvious reasons)

 

[kb2vxa]

Hi Paul and the group,

Since the phone company plant tech simply disconnects your line from the frame you still have a connection all the way back to that point, one heck of a long wire and that means a great LF antenna. They're right though, unwanted surprises can happen when the cable pair gets reassigned. Then too I would never trust the lightning protection for anything, people have been zapped and worse talking on the phone during a thunderstorm. That may be a bit extreme but still a charge can build up and damage sensitive radio equipment.

The best way to avoid problems and still utilize that very long cable as an antenna is capacitively couple to it. First, if you took some uninformed advice and disconnected yourself at the service box on the outside wall of your house, plug it back in unless you only want the house wiring as an antenna which is perfectly OK for some applications on higher SW frequencies. Connect to the yellow or black lead inside the wall jack where your phone plugged in, they're not directly connected to the outside. Stray capacitance between that wire and the others will effectively couple RF to it and you'll be using the full length of the wiring all over town as an antenna.

While this is WAY longer than what you actually need for AM broadcast and SW reception it doesn't hurt a bit. It is particularly useful though for listening to those signals way down at the bottom of the spectrum if you have a receiver that goes down there like my Icom 706Mk2G.

That brings up an important point, it's worse than useless for FM broadcast and other VHF frequencies. For best reception you need a proper antenna with the elements cut to the right length for the band(s) in question.

 

[loumaag]

... First, if you took some uninformed advice and disconnected yourself at the service box on the outside wall of your house, plug it back in unless you only want the house wiring as an antenna which is perfectly OK for some applications on higher SW frequencies. Connect to the yellow or black lead inside the wall jack where your phone plugged in, they're not directly connected to the outside. Stray capacitance between that wire and the others will effectively couple RF to it and you'll be using the full length of the wiring all over town as an antenna.

Warren,
This is reckless advice and the truely "uninformed" person is you. How do you know what wires are connected at the access point? You seem to have a habit of speaking to subjects you seem to know little about but profess great knowledge. This includes your stupidity expressed in the railroad forum (where you advise people to hide and "spring out" at trains to take pictures), your less than knowldegeable advice in the HF forums on all manner of HF subjects including amateur radio (which apparently you know little or nothing about with your Tech class license) and now you are recommending continuing a dangerous process (and I might add illegal) of hooking into the telco lines. How do you know which wires are actually used, if you had ever worked on telephones you would learn that rules are there becuase there are always exceptions.

TO: paulhusker
Sir, do not continue to keep your household telephone wiring as your antenna as long as it is still connected to the Telco's circuit at your access point. Also, be wary of advice given by know-it-alls such as Warren in the above post. :shock:

 

[bsavery]

Hi Paul and the group,

Since the phone company plant tech simply disconnects your line from the frame

WRONG! When you terminate service, the phone company, in probably over 99% of the cases, will simply turn the port off in the phone switch via programming. The techs in the RCMAC center have no way of knowing WHY service is being terminated, just that it is. And they know that most likely, fairly soon they'll be working another order to turn service on for a new customer at that location.

Not to mention they rarely, ever, disconnect the cables at the CO frame. Unhooking wire-wrapped and soldered connections is way to time consuming. Instead they re-assign pairs and re-crossconnect at the access points along the route.

you still have a connection all the way back to that point, one heck of a long wire and that means a great LF antenna. They're right though, unwanted surprises can happen when the cable pair gets reassigned. Then too I would never trust the lightning protection for anything, people have been zapped and worse talking on the phone during a thunderstorm. That may be a bit extreme but still a charge can build up and damage sensitive radio equipment.

Yup... one long antenna... running parallel to power lines in most cases (especially residential!)... more than enough induced current to turn just about any radio receiver into a nifty paperweight!

The best way to avoid problems and still utilize that very long cable as an antenna is capacitively couple to it.

The best way to avoid problems is to NOT utilize the telephone network as an antenna! Not only will he save himself from a potentially fried radio, he'll stay out legal trouble from hooking FCC part 68 certified equipment to the PSTN!

Of course now if you can provide a FCC ID number and REN to the telco on demand, you might avoid that little $20k fine. Oh... almost forgot... you have to provide the telephone number the equipment is tied to as well.

First, if you took some uninformed advice and disconnected yourself at the service box on the outside wall of your house,

I hope for his sake he took that advice!

"Uninformed"?! Just how many years have you been working as a telephone technician?!

plug it back in unless you only want the house wiring as an antenna which is perfectly OK for some applications on higher SW frequencies. Connect to the yellow or black lead inside the wall jack where your phone plugged in, they're not directly connected to the outside.

Unless the house ever had a second phone line installed. Not to mention, if it's old enough, it could possibly have had the old Princess phones with the lighted dial in the house... in which case, if no one ever thought to disconnect it (and most prople don't... I still find them plugged in!) then those will have 48v DC on them...... POOF goes the radio.

Stray capacitance between that wire and the others will effectively couple RF to it and you'll be using the full length of the wiring all over town as an antenna.

The LITTLE bit of RF that gets coupled to the wire will prolly get buried under all the noise!

While this is WAY longer than what you actually need for AM broadcast and SW reception it doesn't hurt a bit. It is particularly useful though for listening to those signals way down at the bottom of the spectrum if you have a receiver that goes down there like my Icom 706Mk2G.

Nope... don't hurt a bit at all... if your intending on using that spiffy Icom to test your smoke detectors!

That brings up an important point, it's worse than useless for FM broadcast and other VHF frequencies. For best reception you need a proper antenna with the elements cut to the right length for the band(s) in question.

Gee... one teeny tiny bit of actual useful information from your post. How'd that slip in there?!

Do us all a favor... especially us telecom professionals... keep your "advice" about phones to yourself!

Bob

 

[BaLa]

just disconnet the wires at the point they come into the house, and attach a note similar to this.

"ATTENTION TELEPHONE COMPANY: DO NOT RECONNECT THESE CIRCUITS — WILL DAMAGE EQUIPMENT INSIDE!"

thats what we did with our VOIP line.

 

[paulhusker]

A big thank you to everybody for your input. You've been extremely helpful in protecting my new radio. Thanks!!

 

[kb2vxa]

Loumaag and others like him,

"Warren,
This is reckless advice and the truely "uninformed" person is you. How do you know what wires are connected at the access point?"

30+ years of hands on experience.

"You seem to have a habit of speaking to subjects you seem to know little about but profess great knowledge."

See above.

"This includes your stupidity expressed in the railroad forum (where you advise people to hide and "spring out" at trains to take pictures)..."

Now THAT is an outright, bald faced lie! I strongly suggest you read what >>>I<<< wrote and not make foolish statements based on the one made by someone other than myself! To set the record straight I wrote "keep out of sight" which in no way should be interpreted as like someone wrote "hiding in the bushes" and "springing out"!

"...your less than knowldegeable advice in the HF forums on all manner of HF subjects including amateur radio (which apparently you know little or nothing about with your Tech class license)..."

HOW DARE YOU make such a reckless assumption based on my class of licence or when I was licensed? That assumption negates 30+ years of hands on radio electronics training and experience both professional and private.

"...and now you are recommending continuing a dangerous process (and I might add illegal) of hooking into the telco lines."

There is absolutely nothing dangerous or illegal in what I wrote, once again READ WHAT I WROTE and at least TRY to understand it. To set the record straight once again I made NO mention of "hooking into the telco lines". For YOUR information the telco (telephone company) lines end where the house wiring begins as per company policy and plant practice.

"How do you know which wires are actually used, if you had ever worked on telephones you would learn that rules are there becuase there are always exceptions."

For your information my tech library includes thelephone plant practices and a whole stack of equipment manuals. Now that should tell you something about my knowledge and experience working on telephone company lines and equipment.

Now last but not least, if this sort of inflamitory CRAP continues I shall write off RR as a bunch of pin head morons with nothing better to do than make insulting remarks based on total ignorance and assumptions of what I know or don't know. YOU DON'T KNOW ME and the only one of you who does has more sense. I have seen FAR WORSE on these forums, people who know less than nothing writing nonsense but you see me trying to HELP where applicable, ignoring nonsense where applicable and NEVER do you see ME write things of a highly insulting nature.

In closing I thank all who appreciate my efforts by thanking me in personal messages and numerous e-mail letters. We have had some intersting and highly informative exchanges, some have taught me a thing or two.

 

[loumaag]

Warren,
I am not going to debate with you. You gave reckless advice, and I called you on it. I read very carefully what you wrote and it was after I did so that I posted my reply that you so poorly quoted above. Apparently I am not alone in the opinion that your advice was poor.

I will take exception to you calling me a liar, however. See if this bit of advice you offered to a new railfan sounds familiar:

...Most railroads these days forbid photography and are extremly jumpy concerning tresspassers. Unless you get permission IN WRITING to photograph specifying where and how you can easily get busted by the railroad bulls. In most cases all employees have standing orders to report tresspassers and photographers even if they're not on company property.

There is a way around it, guerilla warfare. Stay out of sight until the train approaches, shoot your photos and run. By the time the engineer radios the dispatcher and he calls the police you're long gone. Whatever you do don't get caught, the least that can happen is you get chased with a stern warning, the worst is a stiff fine and possibly community service or jail, maybe a combination. Even if they cut you loose you could lose your camera and have a tough time getting it back and if it's damaged, tough. I have heard horror stories, don't you be one of them.

For anyone interested, this particular post can be found right here. And, I will admit right here that you didn't use the phrase "spring out" in your reply, but that is what you describe.

As to this from above:

Now last but not least, if this sort of inflamitory CRAP continues I shall write off RR as a bunch of pin head morons with nothing better to do than make insulting remarks based on total ignorance and assumptions of what I know or don't know. YOU DON'T KNOW ME and the only one of you who does has more sense. I have seen FAR WORSE on these forums, people who know less than nothing writing nonsense but you see me trying to HELP where applicable, ignoring nonsense where applicable and NEVER do you see ME write things of a highly insulting nature.

Sir, you are right. Not only don't I know you, but I don't want to. I only know what you write, not what is in your head. What I do know is that you have gone back and brought long closed topics back up, posting things that have absolutly no relevance in the present. You have posted incorrect and sometimes dangerous information (such as above), so if you are called on it, it would be better to admit your error, or better yet don't speak on matters when you don't have the right information. As to the one person who knows you and has more sense then the rest of us pin head morons, I guess I will just take your word on that.

 

[kd7rto]

The best way to avoid problems and still utilize that very long cable as an antenna is capacitively couple to it.

Someone who boast of 30+ years of experience, yet doesn't know that capacitance will not stop line surges???

What else does this Warren guy do, get on the CB and tell obvious newbees that it sounds like they have a loose board, and to open the case and torque down all the little screws in cans as tight as they can?

Or is he busy downtown, explaining to the detectives why he was lurking in the bushes?

 

[Al42]

The best way to avoid problems and still utilize that very long cable as an antenna is capacitively couple to it.

Someone who boast of 30+ years of experience, yet doesn't know that capacitance will not stop line surges???

What else does this Warren guy do

He's what, when CB first came to be, we used to call an "instant expert" because he immediately has the answer to any question - even if he has to make it up as he goes. (He makes "those who pretend to know everything really piss off those of us who do know everything" seem like more than just a gag line. Maybe just replace "everything" with "anything".)

 

[N_Jay]

OK, you guys cut it out!

I mean, you would never catch me carrying on such a petty argument. :wink:

Yur telephone lines are at best a random collection of wires that may or may not be connected directly or indirectly to other electronic equipment.

Now if that is what you want to use as an antenna, great, but it does not make much sense.

Why don't you try the heater ducts? The water or gas pipes? Sure they are grounded, but so are most antennas (at DC).

At least they won't have 48VDC, or 100 VAC (Ringing) on them ever.

Learn a little about antennas, and apply iot rather than trying things without a hint of understanding.

 

[loumaag]

With that, and since paulhusker has gotten his answer long ago, I guess this better be shut down while it is still somewhat civil. :?

Topic closed.