Over the air digital TV. Clothes hanger antenna.

[sparkeyjames]

Yes romex will work. Use the 12 gauge. 14 is too thin.

[geopilot]

For those people with Dish systems you can run the antenna signal into the house on the same cable as the satellite dish..

Dang- wish I had known this last week- I just spent Sunday evening running a separate wire thru the wall right next to my Dish coax- but the broadcast digital signal and picture quality are awesome on a new plasma.

[dielectric]

I actually built one of the DB2 replicas as shown on the Lumenlab site. It works really well, and hides in the attic. I did have to get a 300-ohm balun, so it wasn't exactly free but very cheap anyway.

The copper house wire would theoretically work better than the steel wire because of the conductivity. They compromise with steel antennas and make then a few percent different longer to compensate, actually. The ham radio guys call it velocity factor, which is as good a term as any, I guess. Copper is a better conductor and would fit better to a calculated wavelength. If you're really into it, check out an ARRL antenna book at the library, just about everything you need to know is in there. Otherwise, just copy what tons of others have done ahead of you.

The Silver Sensor is supposed to be a really good indoor, set-top antenna for those who don't want to run a long length of co-ax. It's a log-periodic dipole array, so it sort of looks like a fern leaf. It's a decent wideband antenna for UHF.

VHF antennas, due to the lower frequencies, are a lot bigger and more of a PITA to get right and cover a good range of channels. The easiest one is a folded dipole, sort of a T made from the flat 300-ohm TV cable, but the bandwidth is sort of low so it doesn't pick up a good channel range.

The antenna amps are mostly junk. If it doesn't plug in to the wall it really isn't going to do anything, but even if it does, they're of such low quality that you likely won't see any benefit. I tried one because I'm a sucker. Maybe if you spend major bucks on a pro-grade one, you'll see something, but better antenna gain and placement will help more.

I actually an an electrical engineer, so this stuff is somewhat interesting to me. Usually I'm working in the 2.4GHz band, where things get really wacky for often unforseen and unseeable reasons. VHF/UHF is like a vacation!

[thrytis]

Can anyone explain how an unamplified coat hanger antenna can get better reception than an amplied antenna? I'm not saying I doubt the coat hanger version, I'm just trying to understand what make the coat hanger one better.

You can add an amplifier to a coat hanger antenna if you really need one - they aren't really part of the antenna, just attached to the line coming from the antenna. From what i understand, amplifiers are most useful if you have a long run of cable to your TV. They introduce some additional noise to the line, so in some cases they can adversely impact your reception.

[jking]

The antenna amps are mostly junk. If it doesn't plug in to the wall it really isn't going to do anything, but even if it does, they're of such low quality that you likely won't see any benefit.

I don't know how you can have an amplified antenna if it doesn't plug into the wall. I haven't touched the amplifier knob since we've been running digital, but, I certainly don't agree with your statement as it applies to analog signals. I currently am using a nine year old amplified antenna that I bought for about $30. I'd used non amplified rabbit ears before & they never worked well. When I hooked the amplified one up to the old TV, it made a huge difference. The amplifier would boost the signal a very noticeable amount.

[dielectric]

I don't know how you can have an amplified antenna if it doesn't plug into the wall.

There are some el-cheapo "amps" out there that claim 3dB gain or so, but no external power source. Total junk. I think your amp works so well because it's 9 years old! The newer ones have been cost-reduced to the point of uselessness. They certainly amplify, but the manfs have stripped out any filtering so you get a nice boost in noise floor, too.

[dkerfoot]

From what i understand, amplifiers are most useful if you have a long run of cable to your TV. They introduce some additional noise to the line, so in some cases they can adversely impact your reception.

Exactly right. An amplifier can't create a signal out of nothing. If you have a strong clean signal, they can help overcome the impedance of a long cable run. For that reason, they make a lot of sense on external antennas.

More often than not, the cheap "amplified" set-top antennas do more harm than good (meaning an non-amplified antenna would work better, not that it would be better to have no antenna at all).

Amplifying a crappy signal results in a big crappy signal. All amplifiers will actually add additional noise. Since a set-top antenna by definition doesn't need to overcome a long cable run, they rarely benefit from an amplifier.

The exception to this would be very high quality (expensive) antennas that have very good amplifiers with very good filter circuits. They might be able to produce a usable signal on a station that is just out of range of a non-amplified antenna.

Why do so many cheap antennas include amplifiers? Because people will buy them off the shelf when they are sitting next to an non-amplified model and because an amplifier only adds $0.10 - $0.50 to the cost. As integrated circuits for amplification have gotten cheaper, the components for a good filter circuit have not. Hence the tendency to slap in an amplifier with impressive sounding specs, but not the additional components that would actually help the performance of the device.

.

[wbsettle]

The beauty of the DIY bowtie is you can optimize the critical dimensions (bowtie length and vertical spacing) for your target TV stations. The commercial bowties, such as the DB2/4 and 4228 models, have to compromise dimensions for packaging, shipping, aesthetics, and overall full spectrum use.

Digging through the Lumenlab thread can be a bit painful. For a DB4 type clone, you want to find the wavelength of the channel roughly in the center of your target stations. The length of each bowtie element is optimally .86 * wavelength. The optimal vertical spacing is .815 * wavelength. You'll also need to pay attention to crossing over the lines of the top and bottom most elements and not letting the lines touch.

For example, I built one of these for my dad a few months back since Dish doesn't have locals in HD in our market, yet. Center of target channels was roughly channel 37, which has a wavelenght of 1.615'. Bowtie elements were cut to roughly 16.75"ish from leftover 14/2 Nomex I had in the parts bin (stripped insulation completely)...the bowtie is relatively forgiving of length variation. Vertical spacing of the "V" in the bowties was 15.7"ish. Since conductivity is part of the requirements (thus the stripping of coat hangers), I picked up some large brass washers to use as the hold down at each connection point.

My dad's getting 75% or better signal readings using the OTA tuner in the Dish VIP 722 box. Field of view, using tvfool.com's information, is at least 50° off axis. Without a reflector, he's picking up stations 30-40 miles away from both sides of the antenna.

-Brent

[monii]

Hello,
Yes sir Woody is right i think that would work. i also try to get some more information about it. all of you gave great information. thanks for sharing.

thanks!!

[Black wallnut]

Hello,
Yes sir Woody is right i think that would work. i also try to get some more information about it. all of you gave great information. thanks for sharing.

thanks!!

Welcome to BT3Central! Not sure why you wish to bring up a thread over a year old though!

[aggrex]

Its an old thread but it might be still relevant. Some folks have discovered that they can pick up some HD channels, eliminate a cable bill and new versions of the "old" rabbit ears are being sold to capture these HD channels. Cable guy was actually impressed that my antenna was sharper than the cable he was installing.

[jbrain]

I have had Direct TV and now have Surewest, which is a U-verse clone using Microsoft Mediaroom. The Hi-Def with my bowtie homemade beats both of them in picture quality.

[crybdr]

Here's a pic of my 3$ HDTV antenna probably similar to the OP's. It's made of coat hangers (sanded to remove the coating where the pieces touch) and miscellaneous parts hanging around the shop. This was done with video plans from the web.



It does as good or better than the store bought antennaes - I have a store bought antenna that feeds the less used TV now.

I get all 12 available channels with it - when I buy a true HDTV, I'm expecting that this will work well....

[sparkeyjames]

Here's a pic of my 3$ HDTV antenna probably similar to the OP's. It's made of coat hangers (sanded to remove the coating where the pieces touch) and miscellaneous parts hanging around the shop. This was done with video plans from the web.



It does as good or better than the store bought antennaes - I have a store bought antenna that feeds the less used TV now.

I get all 12 available channels with it - when I buy a true HDTV, I'm expecting that this will work well....

Hey that kinda sorta looks exactly like the one I made only different.

[woodturner]

Cable guy was actually impressed that my antenna was sharper than the cable he was installing.

Most cable stations don't transmit HD - it requires too much bandwidth, so they opt for more channels instead of a few HD channels. In general, over the air (OTA) HD broadcasts will be better quality than the same program transmitted over cable.