Want to replace old flat tv cable with better coax.

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I have done some reading about balun transformers and how I can connect my existing flat antena cable to 75 ohm cable.
However, my questions is this... what if I replace the 30 year old flat cable all the way to the antenna. Will this yield better reception? (It is pretty good as it is.) The exiting flat cable is starting to fall apart at some places. Currently I just have it directly wired to my coax cable (just before it enters the house) with out any type of transformer. The coax is properly grounded (to the circuit breaker box.)
So my questions are these:
1. How do I connect the coax directly to the antenna? Or should I? Do I still need a balun transformer? 2. If I need a balun transformer, does anyone know of a heavy duty outdoor one? (Or should I build my own.) 3. Will reception improve?
Thanx to all who reply.
jg
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Yes, your reception will improve. You have a mismatched impedience now. Yes, you need a balun transformer. Around $5 at any hardware store, or Radio Shack. If the old cable is deteriorating, it's time to replace it. The balun comes with about 4 inches of flat cable that goes to the 2 antenna nuts, then the coax screws to it and goes to the tv stuff in the house.
Just do it. It's no big deal to do as long as you can get on the roof and to the antenna. Total cost is the balun, some electrical tape, and whatever coax you need. Then tape the coax to the mast with electrical tape. You dont need standoffs for coax.
(Be sure to wire brush the rust off the antenna nuts and coat them with automotive grease.
Mark

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Thanx, I'll try it this weekend. I have some high end coax cable ready for the job. Only one more question... should I worry about the quality of the balun transformer? The ones I have seen at Home Depot/Lowes/Radio Shack look pretty flimsy. I know there is probably nothing inside that should not get wet, but I still wonder...
jg
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I'm not sure what to tell you about the quality of them. I'd guess they are all made by the same company anyhow, but who knows? Use the boot that comes with them, and I tend to wrap electrical tape around that to be sure it stays dry at the coax connector. If water gets inside the balun, it's cracked and bad from the start. They are sealed. As another posted said, replace the screws and nuts on the antenna with brass ones if they are real rusted or corroded.
Mark
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jg wrote:

The outdoor TV antenna baluns are sealed better to prevent moisture from getting inside and degrading the components. They also have a rubber boot to cover the coax connector.
Here are two URL's for Radio Shack TV antenna baluns. The second one has gold plated connectors which should make it more reliable for outside use.
http://tinyurl.com/9codd http://tinyurl.com/dnmxd
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Should I be worried about this? Currently the twinlead only runs from the top of the antenna to where it enters my house. About 40 ft. Then I have coax in my crawl space for another 80 feet or so. 30 ft of which is just coiled and wasted. Reception for local (Sacramento) stations is pretty good. Reception for San Francisco stations is too grainy to watch at times. My zip code is 95682. (So I should not expect too much from San Francisco.)
If need be I can replace the existing twinlead with new twinlead. Should I look into this?
jg
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jg wrote:

If you want the best weak signal reception (San Francisco) either use new twinlead all the way from the antenna to the TV or new coax all the way with an antenna amplifier too. You might want to consider an antenna rotator if the local and distant stations are in different directions. BTW- If you use twinlead, install it with a continuous twist along it's length. Make several twists per yard. I know it's a pain to do this but it helps to reduce the reception of noise from home applicances on the twinlead.
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You haven't told us what type of tv antenna you have, and whether or not you have a rotor. To get San Francisco stations in your area, you must use a rotor as the Sacramento stations and the San Francisco stations are not coming from the same direction. Also, to get the UHF stations from San Francisco, I recommend the Channel Master 8-bay bowtie. It is very common in Sacramento to have separate VHF and UHF antennas as it is fairly easy to get decent reception from San Francisco, Santa Rosa, Concord, Chico, Redding, Reno, and even more, as well as all the local stations. But you MUST have a high-gain antenna with a narrow beamwidth. Otherwise, the local stations will interfere with the distant stations. As in Fresno (where I now live), with a high-gain antenna with a narrow beamwidth, it is possible to get more than one station on the SAME channel, just by turning the antenna. I recommend NOT using any pre-amp at the antenna as the powerful Sacramento stations will wipe out most of the distant stations. Generally speaking, in the Sacramento area good coax cable will work better than twin lead, especially if you are around any electrical interference. Also, even twisted twin line can pick up signals that may interfere with the distant signals. But DON'T have several feet of coax wound up in your attic. Every foot of lead, whether twin lead or coax, adds to signal loss. Generally speaking, the antenna should be mounted as high as possible, although this is not always the case, especially with UHF signals. There is never a guarantee as to what you will receive. As far as using a balum at the antenna (and at the tv if necessary), all balums are NOT created equal. Different samples from the same manufacturer can vary greatly in the amount of signal loss, etc., especially at the UHF frequencies. For the antenna AND balum, I recommend staying away from Radio Shack. In Sacramento, the most popular antennas for picking up San Francisco, are made by Winegard and Channel Master. The BEST UHF antenna you can use is the Channel Master 7-foot parabolic but strong winds can cause problems if the mast is not strong enough. I used the 7-foot parabolic on a 30-ft. mast with rotor and got excellent reception from most of the UHF stations from San Francisco. Second best is the 8-bay bowtie. For more information, read my article in RADIO ELECTRONICS magazine, August 1982, titled HOW TO SELECT THE BEST TV ANTENNA. You should be able to find that issue at a library.
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I couldn't tell you what kind of antenna I have if my life depended on it. It is big and it is very high. At least 40 feet high. If memory serves correctly, I only have one antenna for both VHF and UHF. (Too dark to see right now.)
As for the direction, both the Sacramento and the San Francisco stations are in the same general direction. I am about 40 miles East of Sacramento and given that the Sac antennas are in the Delta by Stockton, I pick up San Fran stations as well. Ironically the station that I really want to pick up does not come in at all, it is Channel 19. (I want my kids to watch Spanish cartoons and I refuse to pay for cable.) I think Channel 19 is East of Modesto some place. (I had a link to a site that pinpointed all towers on a map but I have since lost it. Maybe someone here knows of the site.)
So as of earlier reading I was leaning towards coax, then twinlead (to minimize loss) and now I'm confused all over again.
This is basically a summary of what I have gleaned from you gusy...
Coax: Pros: --Easy to install. --Less suseptible to interferance. --I have a huge roll ready for deployment. Cons: --More lossy
Twinlead: Pros: --Less lossy Cons: --More difficult to install. --Must twist. --Must purchase about 100 ft. --Must purchase hardware to keep away from mast and wall.
Come the weekend, I'm doing one or the other... so I better decide by then.
Thanx again to all who replied.
jg
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Your best off to use RG6, if using coax. Its lower loss than the more common RG59
You can avoid all these issues by getting satellite TV! In most areas of the country they carry lour locals.
all conveient on one pizza pan sized dish, and bets of all they have DVR, digital tv recorders built in.
you record what you want, to watch anytiome you care to, and can skip thru commercials. one version is called TIVO. a hour of prime time has 15 minutes of commercials, well thats now my time to do with as I wish!
satellite tv has free installs, with no commitments if you get the right package. you have nothing to lose!
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Funny that you mention that. I have a linux box that I've setup with MythTV. I've also tried Freevo.
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jg wrote:

Not to get too far off-topic, but how's that working out for you? I've always been intrigued by the idea of MythTV.
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The website you are referring to is located at: http://www.antennaweb.org/aw/Address.aspx - but be careful using this site. With your zip code, you might get the idea that your local stations and the San Francisco stations are in the same direction. NOT SO. They list so many channels in that same GENERAL direction that you really can't decipher from that website which direction the signal is coming from.
The Sacramento and San Francisco stations are NOT located in the exact same direction. That is why you need a highly directional antenna with a very narrow beamwidth. You can separate the locals from the Bay Area stations. You can "pick up" the San Francisco stations when the antenna is pointed towards the Sacramento towers, but you can get a STRONGER signal when turning the antenna towards Mt. Sutro (San Francisco towers), and at the same time, REDUCE the local signals, thus giving you a stronger signal with less interference. To help clear up the confusion between coax and twin lead -- First, twin lead must be installed properly - not touching any metal to say the least, as it should be a few inches from any metal. It's not good to install twin lead between walls, etc. As far as loss goes, coax is consistant regardless of the weather. Twin lead losses can be greater than coax during wet or damp weather. To have low loss, twin lead must be dry. Also, twin lead is more suseptible to breakage during high winds. You want the SAME lead in all the way from the antenna to the television. Don't mix twin lead with coax. You might get excellent reception of the local channels, but it can make a big difference on distant reception. IF your antenna is high gain on UHF, has good directional characterics, you should easily get channel 19 from Modesto UNLESS there is a mountain near you blocking signals from that direction. However, channel 14 in San Francisco is also Univision. I have picked up weak signals from channel 14 even here in Fresno. I can tell you this - When living in Fair Oaks, I had the largest Channel Master UHF/VHF antenna available, installed on a 40-ft mast with rotor and I could NOT get any signal on channel 14. But my neighor had a cheap, small antenna mounted on the chimney and got a good signal on channel 14. Higher is not always better on UHF. Also, ANY bad balum OR even twisting wires combining coax to twin line can totally wipe out some UHF frequencies.
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Here's a link to a picture of my antenna, maybe someone can tell me what I have. Also, does the fact that the "receivers" are off place and therefore touching affect the signal? Since I will be up there, I will straighten them, but odds are they will get crossed again. (I've aready fixed this in the past.)
http://www.acequality.net/temp/antenna.jpg
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jg wrote:

It appears you have the Radio Shack model VU-120 antenna. The best information I can get on this antenna is: gain is only fair to good and directivity is probably below average to average. This antenna is made mainly for local/suburb reception, NOT for distant stations. The beamwidth on this antenna is NOT narrow enough - that is why you can pick up San Francisco stations without turning the antenna. NOT A GOOD ANTENNA FOR WHAT YOU WANT TO RECEIVE. Stick with Channel Master, Winegard, or Jerrold brand antennas. They are built to last and have much higher gain and much better directivity. In YOUR case, I would add the Channel Master 8-bay bowtie antenna for distant UHF signals and keep your other antenna for the locals. Otherwise, you are talking about a $200 UHF/VHF antenna. The 8-bay antenna is not high priced, and beats the UHF section of EVERY UHF/VHF antenna on the market that I know of. But it is extremely directional and you will need a rotor. Also, not only is the gain high and the directivity outstanding, but the design of an 8-bay bowtie gives more "signal capture area" because of the large screen behind the active elements. This really helps in mountainess areas and other weak signal areas. The design of the antenna also narrows both vertical and horizontal beamwidth, resulting in less ghosting. If you can barely pick up a UHF signal with your current antenna, chances are the signal will be very good with the 8-bay bowtie. And I'm talking about your current antenna with NEW coax cable, not your current mixed lead.
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More info on your antenna compared to the 8-bay bowtie on UHF signals. The following are approximate figures based on all the information I can find. Your antenna gives an average gain of about 6 db while the 8-bay bowtie gives an average gain of 13.0 db. Depending on the channel, the MINIMUM gain on your antenna is about 0 db while the MINIMUM on the 8-bay bowtie is 9.5. I don't have specifics as to the channels on your antenna. Every 3 db DOUBLES the signal. The average horizontal beamwith of your antenna on UHF is about 31 degrees while the 8-bay bowtie is about 21 degrees. BIG differences. The 8-bay bowtie rejects signals coming from the sides and back several times as much as your current antenna.
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Is this the bad boy you are referring to?
http://salestores.com/chma428bouhf.html
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That's it. http://salestores.com/chma428bouhf.html
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Ok, so is it possible to have both my current antenna pointed in one direction (minus the UHF section) and use this new antenna pointed in a different direction? Then just combine the signal? This would give me the best of both world w/o the need for a rotor.
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Sure. Back in the dark ages, when the UHF channels went up to Channel 83, TV sets didn't have a combined antenna input, instead they had two (usually 300 ohm) inputs, one for each band. To save cable, VHF/UHF splitter/combiners were used if you had an all band antenna. They're bidirectional, the same unit can be used either way. So you can run two antennas into the one cable.
Mark Zenier snipped-for-privacy@eskimo.com Googleproofaddress(account:mzenier provider:eskimo domain:com)
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