# Bare wire antennas work well!



## grunes

*Bare Wire Antenna works very well!*
I recently replaced the antenna I had in my attic, with a bare wire antenna.

I did this quite simply, by taking the 25' coax cable (a $5-$10 cable I bought from Home Depot) I had in the attic, which connects to my receiver, and stripped off the last 7' or 8' of outer insulation and shield wire.

The signal is much stronger.

I did this after reading an experiment in which someone claimed that a 6" bare wire was better than most TV antennas. I found that 6" did about as well as my fancy antenna, but longer lengths did much better.

I did not strip off the insulator layer on the bare wire, because that is more difficult to do. I gather its dielectric constant and permeability effects the wire's electrical properties - but am I correct that is only if the outer shield is present?

(BTW, if you actually run an antenna outside the house, it probably needs to be properly grounded and shunted for safety. That's why I did it inside the attic, where strikes are supposed to be unlikely.)

I think it is very possible that many people are wasting a money on fancy antennas...

I would presume that a high gain directional antenna (e.g., a YAGI) can sometimes work much better still, especially if you are trying to separate two strong signals on the same frequency.

Have any of you tried similar experiments?

(May be cross-posted to another forum, at another website.)


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## KyL416

According to your location, you're in College Park, Maryland, which is less than 10 miles away from most of the DC stations, a paper clip could work where you are. If anything the attic antenna was overkill because of how strong the signals are there. Even with a classic VHF rabbit ears/UHF combo you could pick up the Baltimore stations, which are less than 30 miles away.

For people who are 30+ miles away from the towers, unless the TV is facing an exterior wall that has a clear shot of the towers, they'll need an actual antenna, if they're even further away like 50+ miles they likely need an outdoor or attic antenna.


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## grunes

Thanks!

I have not tried a paper clip.

Empirically, I got close to twice as many channels reliably this way, as with the 20" disk marine antenna, and a lot more than I got with rabbit ears.

I think the DC/Baltimore area is a little bit special this way, because it is so flat. Based on the signal strengths that my DVR gives for various channels, which are quite high even for many channels I can't get, I'm guessing that the limiting factor is multipath problems, rather than signal strength - i.e., when a signal goes around a building, tree, or truck, or bounces off the atmosphere, it does so in multiple ways, with slightly different time delays, which add together to produce a very complicated looking signal at the receiver. That wouldn't have been much of a problem with the old analog channels (just a bit of ghosting), but it might be confusing digital reception.

(This is further complicated, because we have a number of nearby strong reflectors - a few tall buildings, an almost-overhanging large tree, and a football stadium at the University; plus we are fairly close to a large elevated superhighway - which I am told create a lot of radio frequency transmission problems.)

In contrast, with a more varied terrain, if the signal reaches you at all, most of the objects between you are below the line of sight, and don't affect transmission, so there are fewer objects in the way.

In my case, the higher I mounted the antenna, the better it worked. Even a foot or two makes a big difference. That suggests to me that lifting the antenna out of the main multipath interference zone helps. In particular, maybe it means that direct line of sight transmission, which is hopefully the strongest component, works, and over-rides the weaker multiple bounce and diffraction paths.

I'd bet a really fancy digital receiver could be designed to fix multi-path problems, by adaptively finding the inverse convolution that cleans them up best (a classic signal processing problem, used for high speed Internet transmission lines, radar imaging, cleaning up out of focus images, etc.), but that might be beyond the sophistication of an economically competitive HD receiver, such as that built into my TV or into my old Series 3 TIVO box. Especially if the manufacturers assume that no one uses antennas anymore, so they have no need to do it "right".


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## grunes

Oops. Can everything I just said.

With this antenna, it does look like signal strength and distance are the primary issues. We get almost everything within about 20 miles with complete reliability, some things out to 25 miles, and sometimes some things up to 40 miles, based on tvfool.com. That more or less fits with what you said.

I don't want to get into grounding, because it costs money, so I'll stay away from a "real antenna" - though if I feel up to it I could play with some of the home-made designs on the web (a lot of them are made from cheap bare wire, arranged in fancy patterns, and when you get right down to it, a YAGI isn't much more sophisticated than that) and erect them for a few minutes in fair weather on a long stick.

A lot of the channels more or less duplicate each other, or are filled with re-runs and very old movies, leased programming, cooking (how low budget can you get?), and televangelists, but I can't completely blaim that on the antenna.  Most of the mindless recreation shows we like are on cable - BBC America most of all, SyFy, Disney, Ovation, Nickelodian, the weather channel, and maybe a couple of others. Perhaps with so many cable and satellite channels available, broadcast stations don't have the viewership to produce anything with sufficient budget to be interesting.


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## Tom Robertson

grunes said:


> Oops. Can everything I just said.
> 
> With this antenna, it does look like signal strength and distance are the primary issues. We get almost everything within about 20 miles with complete reliability, some things out to 25 miles, and sometimes some things up to 40 miles, based on tvfool.com. That more or less fits with what you said.
> 
> I don't want to get into grounding, because it costs money, so I'll stay away from a "real antenna" - though if I feel up to it I could play with some of the home-made designs on the web (a lot of them are made from cheap bare wire, arranged in fancy patterns, and when you get right down to it, a YAGI isn't much more sophisticated than that) and erect them for a few minutes in fair weather on a long stick.
> 
> A lot of the channels more or less duplicate each other, or are filled with re-runs and very old movies, leased programming, cooking (how low budget can you get?), and televangelists, but I can't completely blaim that on the antenna.  Most of the mindless recreation shows we like are on cable - BBC America, SyFy, Disney, Ovation, Nickelodian, the weather channel, and maybe a couple of others. Perhaps with so many cable and satellite channels available, broadcast stations don't have the viewership to produce anything with sufficient budget to be interesting.


I'm 40 miles from the towers on top of Farnsworth Peak. (Yes, that Farnsworth.) Beautiful straight line of sight to the peaks.

When Fox was testing their first transmitter/antenna, they had a weak signal. I was told many people in the valley couldn't get them reliably. So I put a big boom antenna in my attic, aimed at the tower, and haven't had any trouble getting any of the local channels.

Now that they all have their full power setups, I can do bare wire antennas or other simple means where I can't run a coax from the attic. Works great. 

Peace,
Tom


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## AntAltMike

grunes said:


> I think the DC/Baltimore area is a little bit special this way, because it is so flat.


You'd be surprised. There are little knob-like hills to the north of many College Park reception reception sites that are seemingly too small to have their topography accurately incorporated into the signal strength algorithms.



> Based on the signal strengths that my DVR gives for various channels, which are quite high even for many channels I can't get, I'm guessing that the limiting factor is multipath problems, rather than signal strength - i.e., when a signal goes around a building, tree, or truck, or bounces off the atmosphere, it does so in multiple ways, with slightly different time delays, which add together to produce a very complicated looking signal at the receiver. That wouldn't have been much of a problem with the old analog channels (just a bit of ghosting), but it might be confusing digital reception.
> 
> (This is further complicated, because we have a number of nearby strong reflectors - a few tall buildings, an almost-overhanging large tree, and a football stadium at the University; plus we are fairly close to a large elevated superhighway - which I am told create a lot of radio frequency transmission problems.)


1. Byrd Stadium is the killer, and if you try turning an antenna to get the reflected signal to land in a "null" in the reception pattern, because the three northwest Washington tower locations are spread just over a mile, north to south, a better aim for one channel makes another worse.

2. With digital signals, you can't rely on continuously observing the changes in strength of the ghost image in zeroing in on your best reception azimuths.

3. In northern Silver Spring, I had the most brutal "snow" interference in the evenings at Bedford Court Sunrise. All of a sudden, it would make channels 4 and 5 unwatchable, but because we could see the interference instantly, we always knew exactly when it began. There was a sign on the nearby retail sales plaza that was switched on at dusk that was doing it and we reported that problem to the FCC and it got taken care of, but we might never have found it without the visual, direct picture observation.

4. Not related to the highway, but nearly a decade ago, there was, all of a sudden, a signal being broadcast at about 363 MHz that was KILLING TV signal distribution because, if I had any ingress in my nearly mile-long system, it would overload the successive distribution amplifiers. I had to use half a dozen custom made filters that I put on the inputs of each downstream amplifier to defeat it, but there would be no help coming from the FCC, because I'm sure that whomever was using that frequency was entitled to do so, but it had to similarly be afflicting anyone with a single band residential amplifier.



> I'd bet a really fancy digital receiver could be designed to fix multi-path problems, by adaptively finding the inverse convolution that cleans them up best (a classic signal processing problem, used for high speed Internet transmission lines, radar imaging, cleaning up out of focus images, etc.), but that might be beyond the sophistication of an economically competitive HD receiver, such as that built into my TV or into my old Series 3 TIVO box. Especially if the manufacturers assume that no one uses antennas anymore, so they have no need to do it "right".


About a decade or so ago, I had looked into the commercial, high tech stuff available for cable TV company headends, as I had serious reception problems at a commercial reception site in Charlottesville, and there were a few products that sold for $2,000 each or more. Of course, back then I used to buy CCD color surveillance cameras for $800 and would have to outfit them with $200 galvanometer-style lenses to adjust to the variation in daytime to night time light I had to deal with at the lobby entrances because the electronics did not yet have the dynamic range to cover it, whereas camera I can buy now for - what, $30? - probably outperform my thousand dollar installations.

No company is going to spend much of anything developing multipath rejection circuitry to support broadcast video reception because
1) it is a small market,
2) it is a declining market, and
3) the customer dissatisfaction rate with those products will be way, way too high to make the per unit profit worth dealing with the dissatisfied customers.

Prospective customer dissatisfaction is likely why millions of high pass and low pass "tier trap" filters that were in the inventories of their manufacturers went to landfill. I once bought either ten or twenty cable channel 65 lowpass filters for $6 each because, in addition to them clearing cable TV bandwidth for insertion of locally generated house channels, I could use them to isolate the local Univision broadcast channel 14. At the time I did, I was contemplating using selected tier traps to similarly isolate 7 and 9 from 11 and 13, 33-36 from 38-40 or 42, etc, and someone at one cable TV hardware wholesaler read me quantity numbers in the thousand each for different roll-off points he had in inventory, but a year later, those filters were long gone, and even though I got someone in their sales office to look into their disposition for me - in fact, I had it looked into more than once, by different people - all my trails led to dead ends. No company wants to spend ten minutes of telephone time discussing/arguing with customers whether something they bought is working properly or not.

In another thread elsewhere, someone sent a UHF Jointenna back to Channel Master to test it to see if it worked and they tested it and reported there was nothing wrong with it, so then they posted here that they would like to have someone else test it, presumably because using it did not get them the results that they had bought it to get. One substantial, reputable dealer in northern PG county that could have sold thousands of CECB tuner boxes decided to have nothing to do wit tuner boxes during the CECB phase, because they just didn't want to have to argue with disappointed customers.


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## grunes

Regarding your problems with Byrd stadium, I don't know if it is an issue to me - I am northwards, almost in Beltsville. Also, I moved my antenna around a bit until I got good reception. Though, there is a bit of trade-off there in terms of channel 23 and 24. I posted my final results here:

http://www.avsforum.com/forum/45-local-hdtv-info-reception/793124-washington-dc-baltimore-md-hdtv-472.html

(I am MRG1 on that forum.)

Note the "Q" column regarding reliability of signal.

Note also that someone there posted a picture of a human sized paperclip, and proposed it as a good alternative.

In any event, you are way above my level. I am trying to do stuff on the cheap (a few $), for myself, to see what can easily be done. You were working at a professional level, and can afford good equipment. I'm sure you can do way better.


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