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post #1171 of 4829 Old 12-23-2008, 05:46 PM
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mclapp,

In your post #180's pdfs, you indicate a gauge 12 for phasing lines, then 1/8" for whiskers. By 1/8" do you actually mean gauge 8-9? Or gauge 12 is still fine?
http://en.wikipedia.org/wiki/American_wire_gauge

Because the availability of 15-20 feet of std gauge 12 copper electrical house wiring is something I would recommend to any reader. It is easy to bend the whiskers and to make the phasing line swap (twist around a broom handle for example). Plus it's copper (excellent conductor) and is easy to soldier to phase lines. The red-black (or white-black) wire coats are protecting the copper from oxidation, but unless you pass on this antenna for many generations, oxidation protection wouldn't be a selling point...

Now, another question:

question #10: are the screws and washers interfering by making a big metal mass at the connection point? I have this feeling, based on some pictures and all I have read, that a very sharp V tip for the whiskers (using pliers) soldered to the phasing line on the outer side and glued to the tip of a tiny 1/4 inch wood peg (making the wire float at least 2-3 inches mid air) would be more electrically friendly. Is that ludicrous, marginally or ultimately true?

question #11: the 300-75 ohms balun: this is a RF 2:1 transfo basically, (lowers voltage by half, raise current by 2, ends up lowering impedance by 4 (E/I = 0.5/2 = 1/4). I open these balun, only to see very few turns of wire around ferrite core. Why isn't there like 20:10 turns? Wouldn't more turns limit the dB loss by transforming? (I suspect too many turns raises the each coil inductance too much in those RF frequencies, but I'm not sure if it is the reason here).

question #12: given the dB loss of the balun, what similar antenna would you recommend that has a natural 75 ohms impedance (to avoid the balun so that we can plug straight in the preamp)?
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post #1172 of 4829 Old 12-23-2008, 08:36 PM
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Mclapp is lucky, he has access to old telegraph wire that is about 8 gauge heavily copper-clad steel wire. Structual consideration is important outdoors. Ive found 12 gauge copper wire to be on the flimsy side for outdoor use. I use 10 gauge or even 6 gauge copper. I straighten the wire by putting one end in vice grips and the other end in a vice and hit the vice grips a few times with a hammer. (4 gauge is much harder to straighten)

10) No not ludicrous at all, soldering makes a much better connection. But instead of using a wood peg which absorbs and retains moisture, use a plastic. Screws and washers can intrude into the phasing line spacing, in effect narrowing it. With copper wire, small triangle washers made from copper scrap work great. If no scrap available, flattening 10 gauge or heavier copper wire will make some.

11) I suspect the main reason is one of cost and ease of manufacture. In one study I saw, the balun from a Sega game system had the lowest loss of any, heh. I have a couple of old Atari system baluns that were made in Japan and they do seem to have superior performance over the newer Philips ones I got.

12) A 75 ohm antenna isnt going to eliminate the need for a balun. A balun matches a BALanced line to an UNbalanced line, hence the name. A 75 ohm antenna would need a 1:1 balun, which is not a common item found everywhere. A 1:1 balun can be made from coax, but it would be matching for about one channel only.
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post #1173 of 4829 Old 12-24-2008, 02:50 PM
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d510d180:
There are antennas that can be fed directly with 75 ohm coax. Here is one:
http://www.popular-communications.co...asWeb92708.pdf

It is possible to make a low loss 4:1 balun out of a half-wave section of coax, but it has a limited frequency range. Most of the conventional ferrite baluns have a fairly low loss over the whole band.

It is true that the many minor losses in an antenna system can be additive, but it is more important to have the antenna in the best possible "hot spot" at your location to collect the strongest signal.

If you can not measure it, you can not improve it.
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post #1174 of 4829 Old 12-24-2008, 03:05 PM
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Some antenna manufacturers seems pretty serious when in comes to warnings:
On the page http://www.antennasdirect.com/DB4_HDTV_antenna.html
you can download instructions out of curiosity:
http://www.antennasdirect.com/pdf/ge...structions.pdf
Read the warnings at the very end.
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post #1175 of 4829 Old 12-24-2008, 06:26 PM
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That last warning only applies to the flimsy commercial antennas. By building your own antenna, it is possible to build one that survives many, many tosses.
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post #1176 of 4829 Old 12-25-2008, 06:18 AM
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Ah, but where's the instructions for a homemade edible one?
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post #1177 of 4829 Old 12-26-2008, 01:35 PM
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I just built two of the mclapp antennas with 9.5" whiskers and 9" spacing. Here is the second one that I hooked up to the tv tuner card on my computer:



The mast is 0.75" thick x 1.25" wide pine, painted white. The standoffs are solid white plastic, screwed into the side of the mast with drywall screws. They're 1" above the surface of the mast. The plastic came from thick shims that'd been attached to the bottom of some above ground pool steps. Don't know what type of plastic it is, but it cuts, sands and holds screws excellently. The mast slips into a support base made of unpainted wood scraps and plywood.

The whiskers are some very heavy copper that came from a scrap of big twisted stranded copper cable. The phase lines are from Romex wiring...14 gauge I think. Those lines are soldered to the whiskers. I just took a straight phase line, marked the whisker locations and used a plumbers torch to solder the wires together. Then, I screwed the assembly onto the standoffs and added the twisty cross-over bends at the same time.

The balun and coaxial are from Lowes. The balun is screwed to some flat copper tabs soldered to the phase lines. The whisker mounting screws are recycled from some old kitchen cabinet hinges. No washers needed...I made the whisker bends by bending the copper around a nail and crimping it about 3/4 around with pliers.

I didn't include a reflector screen because the stations I want are from two different directions. Most of my stations are about 20-30 miles distant.

My first mclapp antenna replaced rabbit ears on an old tv that has a digital converter box. I hung the antenna in the corner window of a second floor bedroom. I went from about 8 stations there to receiving 22 stations. I was literally shouting with amazement at how much my tv reception had just improved!
The antenna pictured is hooked up to my computer. Reception there is a bit less because of the location in the house...most of the house and a few evergreens are between the antenna and the tv signal source.

Overall, for the price of only the baluns and coax and my time to build it, I'd say it was a worthwhile project. I'd really thought I was going to need a big rooftop antenna, a preamp, grounding rod, splitter, and a 100+ feet of coax etc. just to stay in the digital age. Instead, two inexpensive antennas got me the same results, all without monkeying around up on the roof. Thank you to everyone who has posted info in this thread!
LL
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post #1178 of 4829 Old 12-26-2008, 03:13 PM
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Quote:
Originally Posted by elmoleaf View Post

I just built two of the mclapp antennas...

Nice job, elmoleaf! Welcome to the forum.

If you can not measure it, you can not improve it.
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post #1179 of 4829 Old 12-26-2008, 07:15 PM
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Nice!

Quote:


The plastic came from thick shims that'd been attached to the bottom of some above ground pool steps. Don't know what type of plastic it is, but it cuts, sands and holds screws excellently.

Good find. It should also be good for outdoor use as it should have some UV resistance. (It could be Derlin ??)

Quote:


Instead, two inexpensive antennas got me the same results, all without monkeying around up on the roof.

Outdoors, the reception would be even much better. You could replace that wood with square plastic balisters. (5 pack at Lowes approx $12)
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post #1180 of 4829 Old 12-27-2008, 12:56 PM
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elmoleaf,

Welcome to the forum.

Great job, especially the use of scrounged materials! The antenna looks really well built and it sounds like it performs as well.
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post #1181 of 4829 Old 12-27-2008, 04:19 PM
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Question about the reflector. Where is everyone getting their material? The only stuff I can find comes in 50ft rolls (2X3 cage wire). Anyone found any in smaller rolls? What kind of businesses should I call around to see if they have anything and what should I ask for? Lowes and Home Depot both have the cage wire in the 50ft roll but nothing smaller that I could find. Thanks for any suggestions.

William
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post #1182 of 4829 Old 12-27-2008, 08:14 PM
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Just finished my 2nd DB4. Sigh...

I used the same specs as elmoleaf, the specs from mclapp's 9.5" whiskers 9" bay spacing. Using gauge 10 copper (house wiring), I have been soldering the phasing lines to whiskers and swapped the phasing line in mid air. I also glue-gunned the 8 contact points to 4.5 inches plastic pegs (from plastic coat hangers) inserted in holes in a pine wood 3/4" X 1.5". The balun goes perpendicular to phasing lines, straight toward the wooden mast, in which I made a hole to pass the RG6 coax cable, so that it interferes the least possible with any element.

To recall the 1st antenna, it was a 12 gauge copper, with 7" whiskers and 5.75" bay spacing, laying flat on a similar pine wood mast, not soldered but using screws and washers.

I was expecting a better VHF-hi reception, without loosing much of the last channel that materred (46). I was also expecting a better reception of the lower UHF.

Guess what. None of my hopes came true. The VHF is the same and all UHF is worse.

question #13: could the tin possibly be reducing conductivity in a harmful way, relatively to copper?

Coax push-on connectors are not causing any significant loss, from what I could tell, as I used them all with my 1st antenna and it is still better. But:

question #14: are all balun pretty much causing the same loss? Should I be concerned with quality here?


Before I start posting to the LG tv owners forum, I have a few generic questions. I have some ghosting (ntsc) especially on VFH 10, actually 2 main ghost images that are ~10% and ~20% on the right (and lots of very weak others). I suppose have multipath reception (I am in an urban area, first floor).

Given the ntsc 30 frames/s, at 525 lines/frame means one line is ~60us (removing the horizontal sync). 10% of this is 6us. At the speed of light (300m/us), that would be 1800 meters, right?

question #15: Should I conclude this is a sky reflection? Because how could the signal be retarded by nearly 2 km so cleanly? I mean, there is no gigantic metallic wall 1km behind me... I though that only shortwave (well below VHF) could bounce off the sky...

question #16: Could it be a defect in the TV tuner? Have you heard of such tv tuner problems?


I am so disappointed. My 15 years old cheap 200$ 14 inch CRT could tune a nearly perfect image with rabbit ears, and this 1000$ fullhd tv threw me in this antenna adventure... Not that iit is not a lot of fun.

I need suggestion guys, because I am about to return that piece of junk to the store...

question #17: Is there anything else I could do to help clean up the SD and DTV reception? Are the modern tv tuners equipped with auto-magic multipath elimination?!!

(Sigh)
:-)
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post #1183 of 4829 Old 12-27-2008, 09:10 PM
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Quote:


Where is everyone getting their material?

Both my Lowes and Home Depot sell overpriced 5 and 10 foot rolls of 2 X 4 fencing material. You can also go to fencing companies found in your yellow pages. They may sell you end of rolls cheap or given the small amount needed, give it to you free as a sample.

Tractor Supply sells the better (for higher channels) 1 X 2 mesh fencing, but 25ft rolls at $30 is the minimum.
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post #1184 of 4829 Old 12-27-2008, 09:28 PM
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I plan on making a UHF antenna into a painting or some other artwork.

There is no need for the wires to have structural strength as the artwork will support everything.

What is the smallest diameter copper wire that won't cut into the effecincy of the antenna. I'm thinking of a DB-2 clone without a reflector.

I've made a simple loop antenna out of 30 gage (0.010") wire that worked OK but I don't know if that's too small for optimum signal strength.
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post #1185 of 4829 Old 12-27-2008, 09:28 PM
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Quote:


Guess what. None of my hopes came true. The VHF is the same and all UHF is worse.

Post some pictures. Sometimes just a little thing can make a big difference.

13) No, but bad solder joints can.

14) All baluns are not alike. From what Ive read, Radio Shack ones are on the bottom and Channel Master ones are tops. Baluns from old Sega game systems seemed to be the very best, but arent weather-proofed.

15) No, not sky reflection. If your calculations are correct, keep in mind 1800 meters is over a mile in radius. It could be any building or any larger metal thing.

16) Unfortunately, AFAIK the tuners in current TVs are not the newer 6th generation tuners found in converter boxes. The older generation tuners are not as good in dealing with multi-path (ghosting in digital).
Taking it back to the store and complaining is not a bad option. It could be a defect. If not, at least youre registering a strong complaint by demanding a different set.

17) Aiming and location. Just a small adjustment in height or direction can make a huge difference.
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post #1186 of 4829 Old 12-27-2008, 09:29 PM
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Quote:
Originally Posted by wmbjr View Post

Question about the reflector. Where is everyone getting their material? The only stuff I can find comes in 50ft rolls (2X3 cage wire). Anyone found any in smaller rolls? What kind of businesses should I call around to see if they have anything and what should I ask for? Lowes and Home Depot both have the cage wire in the 50ft roll but nothing smaller that I could find. Thanks for any suggestions.

William

Our local Lowes sells hardware cloth in 12 ft long by 3 ft wide rolls. The local farm store (Cal Ranch) had huge rolls and sold me a 3 ft by 3 ft piece (priced per foot). Their price was outrageous though. It was about 2/3 the price of the 12 ft roll at Lowe's. Grrrr. The clerk that cut it didn't know the price but based on the roll price ($/ft basis), I figured I was going to come out okay... Oh well, at least I don't have any leftover fencing...
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post #1187 of 4829 Old 12-27-2008, 09:36 PM
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Quote:


What is the smallest diameter copper wire that won't cut into the effecincy of the antenna. I'm thinking of a DB-2 clone without a reflector.

Smaller wire has a little less bandwidth, but that may not be a concern for you. 30 gauge can be fine except that structually, its very floppy and the antenna will distort. That will affect gain very badly. With something that thin, youre better off with a hanging Gray-Hoverman design.

As far as artwork is concerned, getting creative with the reflector has lots of possibilities. Just try to keep most reflector wires horizontal for the most gain.
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post #1188 of 4829 Old 12-28-2008, 12:28 PM
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Quote:
Originally Posted by 300ohm View Post

Smaller wire has a little less bandwidth, but that may not be a concern for you. 30 gauge can be fine except that structually, its very floppy and the antenna will distort. That will affect gain very badly. With something that thin, youre better off with a hanging Gray-Hoverman design.

As far as artwork is concerned, getting creative with Just try to keep most reflector wires horizontal for the most gain.

Thanks for the info.

>30 gauge can be fine except that structually, its very floppy and the antenna will distort.

For the quick & dirty loop I just ran the wire in a "S" shape through my fingers until it was stiff enough and had the right cast (about 7.5" diameter). For the new antenna the artwork should support everything.

>the reflector has lots of possibilities.

I'm thinking of something flat with no reflector that hangs like a painting. DB-2 sized.
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post #1189 of 4829 Old 12-28-2008, 03:39 PM
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Another question regarding the reflector material. Any reason not to use a galvanized wire? I found some galvanized 16 gauge for a decent price, but the mesh that is not galvanized is about $25 for 50ft of which I need about 3-4 feet total. Thanks.
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post #1190 of 4829 Old 12-28-2008, 04:17 PM
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d510d180,

Sounds like you may have multi path problems with all the ghosting you're getting on the analog signal. Post a picture of your build maybe we can see something that may help with the antenna.

A reflector will help with multi path problems sometimes, depending on the source of the ghosting.

I have a Samsung LCD TV that has very good multi path rejection and my Zenith DTT-900 STB is excellent.


wmbjr,

Galvanized wire is fine, any wire mesh that has wires spaced a max of 2" apart and running horizontal will work fine for UHF. 1" is even better the closer the spacing the better the rear rejection and slight gain increase.

A while back I made a reflector out of #18 galvanized wire and strung it back and forth an inch apart in a PVC frame and it worked great for a reflector. The same could be done with a wood frame as well and you can buy a whole roll of wire that size for less than $10.

I want to do a test using poultry fence (chicken wire) sometime, that stuff is cheap and very common the problem is that it doesn't run truely horizontal but it may be good enough. I've heard of people using it with success in a few different antennas.
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post #1191 of 4829 Old 12-28-2008, 09:34 PM
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Quote:


I want to do a test using poultry fence (chicken wire) sometime, that stuff is cheap and very common the problem is that it doesn't run truely horizontal but it may be good enough. I've heard of people using it with success in a few different antennas.

A while back, I measured the horizontal wire length on 1 inch chicken wire. 2 inch by 4 inch mesh has way more horizontal wire length per square foot.
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post #1192 of 4829 Old 12-28-2008, 09:54 PM
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Hi, Guys. I must say, I've been following this thread with a great deal of interest, and marveling about the various configurations in whisker length and spacing, as well as construction materials used to build these 4-bay, 8-bay antennas. I'm greatly interested in which would likely serve me best in the zip code 18641.

I, too, like many of you, built the YouTube coathanger antenna, and was so impressed with the results, decided to construct a few of these.- One for each TV in the house. I was sadly disappointed upon buying these multiples of amplified rabbit ears, and the seeing what these cheap, homemade coathanger antennas could do by comparison!

I built mine all as per the instructions on the video, using coathangers on a piece of wood (1"X3"-3' long) I used ordinary drywall screws and steel washers.

Then I began brainstorming, and decided if they could do so well indoors, to the point of shaming some rooftop antennas, what could they do if I could raise them onto the top of my roof?- Then I began to wonder how the steel coathangers, steel hardware and ordinary pine board might fare over time in the weather, regarding rot and rust, and began to concoct a design based on the YouTube antenna, constructed on a pressure treated board of the same size, utilizing all brass hardware and ordinary copper wire. (Both superb conductors, and electrically superior to steel.) I also felt the design left a lot to be desired in structural integrity using ordinary wood screws, and chose to drill the board, securing the "whiskers" and balun transformer attachment with all brass fasteners with screws, nuts and a washer on each side of the board.

I ran about 50' of good RG-6 coax cable up the telephone pole outside my house, putting it roughly 35' in the air outside.

The results were nothing short of phenomenal! I cannot attribute the improvement one way or another to any one thing. I dont know if increasing the line of sight, by raising the antenna was responsible, or the use of better conducting material, or both.

I have plans to concoct and build a larger model of the YouTube antenna, using 8 guage copper ground wire for it's construction (on the basis of the theory of more surface area, as well as for outdoor durability) I am wondering, based on my needs, what whisker length, spacing and spread would work best. My understanding is all of the digital stations are located in the same direction, which is southwest, according to tvfool.com . I don't know if the deflector behind the antenna, making it uni-directional, as opposed to omni-directional would help, either.

I still am coming in short on a few stations. Everything is coming in in analog quite well, as far as that goes in my location. I am recieving all of the digital channels now, but some of them drop out frequently, as signal strength is anywhere between 15 and 50, approximately. Some stations are quite strong, while others are a bit weak, pixelize, freeze and drop signal. I'm wondering which variation of the 4-bay, 8 whisker dipole antenna would be best for pulling in the stions available in my area. One other bit of info: we are in a very mountainous area, located in a valley, so we have a large mountain on either side of where we are located. There are also several, very large pine trees all around us, which I'm sure are posing problems, as well.

The following stations are available in my area:

16.1, 16.2 (49)
22.1 (13)
28.1 (11)
38.1 (31)
44.1, 44.2, 44.3, 44.4 (41)
56.1, 56.2, 56.3 (45)
64.1, 64.2, 64.3, 64.4 (32)

Many thanks, in advance, for any experience, knowledge and help.

Best Regards,
Eric
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post #1193 of 4829 Old 12-29-2008, 09:39 AM
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Quote:
Originally Posted by 300ohm View Post

A while back, I measured the horizontal wire length on 1 inch chicken wire. 2 inch by 4 inch mesh has way more horizontal wire length per square foot.

The chicken wire vertical wires are usually not truely vertical but angled so I wonder how that works out. A person may be able to pull on the wire and stretch it so the wires end up closer together and have less vertical angles also.

In the spring I will have to test some at my outside testing range, it would be easier and quicker to do that than build a computer model of it.

It may not be the best stuff to use but the cost to performance ratio may make it attractive to some.
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post #1194 of 4829 Old 12-29-2008, 08:44 PM
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These cooling racks available at the $1 store for 2/$1 are another cheap alternative. (I bought them to cook meatloaf on, as per the recipe on americas test kitchens, heh. Less grease and more even cooking than in a meatloaf pan.)



They are steel 9" X 13" each and the wires are spaced 13/16" inches apart. They are very light but strong, about 14 gauge. An old plastic mini blind rod inserted into the bent out feet can keep them nice and flat, and they could be soldered together. A pair of these behind each whisker could look like the new CM4221 HD model, heh.
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post #1195 of 4829 Old 12-29-2008, 09:15 PM
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Quote:


I'm wondering which variation of the 4-bay, 8 whisker dipole antenna would be best for pulling in the stions available in my area.

The 9 1/2 over 9 would be about the best for after February.

Quote:


One other bit of info: we are in a very mountainous area, located in a valley, so we have a large mountain on either side of where we are located. There are also several, very large pine trees all around us, which I'm sure are posing problems, as well.

Pines and firs are the worst because they have the highest water content % of all leaves and last all year round. Anything you can do to cut down the ones in front of your path would help a lot.
For mountains, try aiming for the top of the mountain to catch the refractions.

Quote:


utilizing all brass hardware and ordinary copper wire.

Yep, you want to use copper or brass hardware with copper wire to minimize galvanic corrosion. With aluminum wire/rod, use aluminum hardware or second choice, zinc plated steel (galvanized) hardware.
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post #1196 of 4829 Old 01-01-2009, 10:25 AM
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Happy New Year, all, and thanks for the reply. It seems as though there is somewhat of a consensus here that an antenna with 9-1/2" whiskers, spaced about 9" apart would be best after February. Would it also best meet the best parameters for my requirements in my location to receive stations in my area? Also wondering if 8 guage solid copper ground wire would serve well as material, and would it be more beneficial than, say 12 AWG cable. I would be inclined to believe with having more surface area, would be better, but might be wrong on this. I am very compelled to use copper based primarily on it's ability to resist corrosion, and due to it's superior conductivity.

Also concerned as to whether it really matters in using the same diameter guage wire for entire antenna. Example: I was contemplating using 8 AWG for the whiskers, and using ordinary 12 guage for the phase leads.

Large copper or brass washers capable of holding down 8 guage wire securely could be hard to find, and possibly more expensive than drilling ordinary pennies. Obviously ordinary wood screws would not suffice, and I would likely use at least #8 brass screws, nuts and washers. Just wondering any thoughts on this,

Also wondering best possible spread of whiskers: 3"? 3-1/2"? 4"? 4-1/2"?

Best Regards,
Eric
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post #1197 of 4829 Old 01-01-2009, 11:23 AM
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Also wondering if 8 guage solid copper ground wire would serve well as material, and would it be more beneficial than, say 12 AWG cable. I would be inclined to believe with having more surface area, would be better, but might be wrong on this.

The differences between 8 and 12 AWG are in the hundredths of a dBi, at most around tenths of one dBi. 8 AWG is much more durable outside. 12gauge phasing lines are also fine. Technically, larger wire has more bandwidth, but since the bowtie has oodles of bandwidth already, it doesnt make any difference.

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Large copper or brass washers capable of holding down 8 guage wire securely could be hard to find, and possibly more expensive than drilling ordinary pennies.

Yep. Make your own from scrap pieces of copper. A triangle shape is really the best fit.

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Also wondering best possible spread of whiskers: 3"? 3-1/2"? 4"? 4-1/2"?

Also minor in difference. I would go for 4 1/2 ".
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post #1198 of 4829 Old 01-01-2009, 11:36 AM
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Quote:
Originally Posted by nepaeric View Post

Also concerned as to whether it really matters in using the same diameter guage wire for entire antenna. Example: I was contemplating using 8 AWG for the whiskers, and using ordinary 12 guage for the phase leads.

It would be better to use the #8 wire for the whiskers and #12 or smaller for the phase lines.

As far as antenna performance is concerned the size of the wire is one of the least critical factors unless you go really large like 1/4" or really small like #26. Both extremes can be used but the antenna dimensions would have to be slightly adjusted.

Quote:


Large copper or brass washers capable of holding down 8 guage wire securely could be hard to find, and possibly more expensive than drilling ordinary pennies. Obviously ordinary wood screws would not suffice, and I would likely use at least #8 brass screws, nuts and washers. Just wondering any thoughts on this,

If you wrap the wire tight to the screw then you should be able to get away with a small washer, take a look at elmoleaf's posting in his pictures you can see where he kept the wire close to the screw for almost 300 degrees then flared out the whiskers.

What I do is get a screw slightly smaller than the one I plan to use for fastening the whisker to the antenna and use that to wrap the whisker wire around. I pinch it tight to the screw with needle nose pliers then spread out the whiskers while holding tight with the needle nose pliers. That will give you an almost closed loop on the end that you can put the attachment screw through

Quote:


Also wondering best possible spread of whiskers: 3"? 3-1/2"? 4"? 4-1/2"?

Best Regards,
Eric

The spread on the whiskers is also a non critical measurement 3 - 6 " will work fine, the spread may make a very slight difference but you will be hard pressed to tell. 5" is a good spread for a 9 1/2" whisker.

Happy New Year
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post #1199 of 4829 Old 01-01-2009, 04:21 PM
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Where can I buy a UHF/VHF transformer?
I live in Toronto, Ontario.

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post #1200 of 4829 Old 01-01-2009, 09:10 PM
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Do you mean a balun ? If so, most hardware stores and home centers and dept stores like Walmart and Kmart.
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