How to build a UHF antenna... - Page 51 - AVS Forum
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post #1501 of 4798 Old 01-25-2009, 09:15 PM
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Quote:
Originally Posted by SonicLogic View Post

There only seems to be one station I can't get. It's WEIQ-DT which is located 51 miles away from me. It's a PBS station with a tiny antenna and relatively low power. It's real channel 41 and virtual channel 42.1. I can pick that station up on my 91XG but it has eluded me on the mclapp 4-bay.

The 4 bay without the reflector is giving away some gain to the 91xg on ch40+ for sure.

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Also, be advised that none of my antennas are yet ready for prime time. I'm still doing work on them. Today I intend to coat all the bare wire and the connections of the antenna in the photo with liquid tape. I want to determine if paint or liquid tape actually degrades reception performance.

I would think a light coat of non metallic paint would be fine I used some poly urethane on one of my test antennas that I made of wood. I put the urethane on the wood, wire connections and screws and didn't see any negative effects.
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post #1502 of 4798 Old 01-25-2009, 09:19 PM
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Yes I used Nylon washers and bolts. I thought the ice cube tray was great because it was only 1 dollar and gives you minimal contact with the feed line and about 2 " of offest from the 1x4. I soldered each bowtie to the feed line then after screwing them down to the ice cube tray put a small about of plumbers goop on it to hold it tight. I then soldered the bauln at the center of the gap and drilled a whole through the 1x4 to keep it nice and straight and behind the elements. Youll have to ignore all the tape and cardboard layign around i havent had time to clean up the area and the stand i have it on is not finished ( still a bit tipsy) the black electrical tape thats going horizontal is holding the antenna to the stand untill i get a final hieght once i do some more testing.

Total cost of the project in Canadian was $16. The nylon screws were probobly overkill but they work great.

1x4x8 + 10 nylon washers bolts and screws $9
ice cube tray $1
1.5 meters of 10-2 coper wire + tape and other random stuff$6

The bowties are 10" long with 5 1/2" spread
9.5" between bowties
1 1/4" feed gap distance
I also bent the bowties forward 2"


I plan to add a reflector at a later date.

PS No steak knives were harmed buring this build! Just a finger! ( be carefull cutting electrical tape with a knife) lol

And the ice cube tray was increadibly hard to cut. i used a pair of scissors because the saw as just not playing nice.
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post #1503 of 4798 Old 01-25-2009, 09:34 PM
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I like your mclapp 4-bay redzone! In all of my builds I've attempted to use items that I already had in my workshop just to keep the cost down. Good job!
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post #1504 of 4798 Old 01-25-2009, 09:53 PM
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Ice cube trays, I originally thought they were styrofoam packing spacers, which actually are better, at least for indoor use.

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1x4x8 + 10 nylon washers bolts and screws $9

Yeah, overkill since you soldered too. A dab of the Plumbers Goop would have held them well after it dried.
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post #1505 of 4798 Old 01-25-2009, 10:13 PM
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i thought about useing styrofoam for teh spacers but due to me wanting to put it outside i figured the icecube tray as the best idea. i plan to cut the ice cube trays so that they come in contact with the feed line less when i bring it in to add the reflector but that wont be for a while. as ctv comes in perfect with this build so i dont need to worry for the supperbowl.
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post #1506 of 4798 Old 01-26-2009, 10:50 AM
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10x9.5 or 10x9.75 mclapp?

Everyone keeps talking about the mclapp 10x9.5 but the PDF files I downloaded a while ago said the phase line should be 9.75 for the 10 inch wisker elements.

Does it make a difference? I'm interested in building a non-reflector version should my 9.5x9 mclapp need improvement after the switch over. I need bi-direction which is why the not-reflector. I'll interested RF channels 7 to 43.

Plans after the switchover:
Plan A. My old mclapp 9.5x9 works. No additional work is needed.
Plan B. Build a mclapp 10x9.?.
Plac C. Build a double bowtie high VHF and use a VHF/UHF combiner should plan B not work.

 

4 bay 10 inch flat elements.pdf 21.7255859375k . file

 

4 bay 9 and 3 quarter phase line.pdf 33.0205078125k . file
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post #1507 of 4798 Old 01-26-2009, 11:03 AM
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Hi, Can I make a 2 or 4 bay UHF antenna by connecting 2-4 of R.S. UHF Outline Bow-Tie Antenna's to one 300 to 75 balun?

I dont have the materials for a DYI but I thought this might work as well. I am looking to pick up channels 18, 19, 36, and 44 (zip code 13790) I currently pick up 19 and 44 with a TERK HDTVO and I am looking to do some experimenting with the UHF channels.

These channels are in different directions, but my real question is;

would connecting 2 or 4 of the UHF Bowties from radio shack to 1 balun work as a 2 or 4 bay antenna? Here is the link to the RS bowtie http://www.radioshack.com/product/in...ductId=2062017

Any comments would be appreciated Thanks!
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post #1508 of 4798 Old 01-26-2009, 01:57 PM
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Quote:
Originally Posted by mclapp View Post

The 4 bay without the reflector is giving away some gain to the 91xg on ch40+ for sure.


As you can see, it wasn't a fair fight for the signal. The 91XG is 25 feet in the air and the mclapp 4-bay is only 13 feet in elevation. Once I give the vent police the slip, I intend to mount the mclapp 4-bay at 25 feet as well. I'm pretty sure it will pull in that weak PBS signal on channel 41. The PBS station has an antenna height of only 600 feet and it's located 52 miles away from me.

Quote:
Originally Posted by mclapp View Post

I would think a light coat of non metallic paint would be fine I used some poly urethane on one of my test antennas that I made of wood. I put the urethane on the wood, wire connections and screws and didn't see any negative effects.

I'll let you know my results.
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post #1509 of 4798 Old 01-26-2009, 05:38 PM
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Quote:
Originally Posted by MikeySoft View Post

10x9.5 or 10x9.75 mclapp?

Everyone keeps talking about the mclapp 10x9.5 but the PDF files I downloaded a while ago said the phase line should be 9.75 for the 10 inch wisker elements.

Does it make a difference? I'm interested in building a non-reflector version should my 9.5x9 mclapp need improvement after the switch over. I need bi-direction which is why the not-reflector. I'll interested RF channels 7 to 43.

Plans after the switchover:
Plan A. My old mclapp 9.5x9 works. No additional work is needed.
Plan B. Build a mclapp 10x9.?.
Plac C. Build a double bowtie high VHF and use a VHF/UHF combiner should plan B not work.


9.75 or 9.5 not much difference, I use 9.75 in my builds and try to cut down on any contact in the phase line area in hope of keeping the velocity factor is high as possable. 9.5 is just a slight tweek to compensate for the drop in velocity factor when the contact area is larger.

The difference in size is more noticable on VHF-hi with the 10x9.75" being better on the lower vhf-hi channels and the 9.5x9' being better in the mid vhf-hi channels. The only place most people would see the difference on UHF would be in the channels above 50 where the 9.5x9 should take over.

If you are looking for a single channel or 2 near by channels on vhf-hi the proper size 4 bay will have as much gain as a 2 bay VHF-hi antenna but if you want a wider range the VHF-hi 2 bay will be better over the whole range.
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post #1510 of 4798 Old 01-26-2009, 06:09 PM
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Quote:
Originally Posted by sustorm View Post

Hi, Can I make a 2 or 4 bay UHF antenna by connecting 2-4 of R.S. UHF Outline Bow-Tie Antenna's to one 300 to 75 balun?

I dont have the materials for a DYI but I thought this might work as well. I am looking to pick up channels 18, 19, 36, and 44 (zip code 13790) I currently pick up 19 and 44 with a TERK HDTVO and I am looking to do some experimenting with the UHF channels.

These channels are in different directions, but my real question is;

would connecting 2 or 4 of the UHF Bowties from radio shack to 1 balun work as a 2 or 4 bay antenna? Here is the link to the RS bowtie
Any comments would be appreciated Thanks!

If you are in the Binghamton area getting 19 and 44 is pretty good since they're out of Syracuse. Ch 18 and 36 analog are out of Elmira and their digital signals are on ch2 and ch55. Those UHF bowties won't do anything for ch2 but you may have a shot at 55. You should be able to connect 2 RS bowties together onto 1 balun. You will have to adjust the lead length for best reception I would guess somewhere around 3-4" would be a good start.
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post #1511 of 4798 Old 01-26-2009, 07:54 PM
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Quote:
Originally Posted by mclapp View Post

If you are looking for a single channel or 2 near by channels on vhf-hi the proper size 4 bay will have as much gain as a 2 bay VHF-hi antenna but if you want a wider range the VHF-hi 2 bay will be better over the whole range.

I'm not sure what you mean by this. After the switch, I am interested in RF:

7, 11, 18, 19, 20, 26, 30, 31, 32, 35, 39, 41, and 43.

Thanks again for all your help.
LL
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post #1512 of 4798 Old 01-27-2009, 06:35 AM
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Quote:
Originally Posted by MikeySoft View Post

I'm not sure what you mean by this. After the switch, I am interested in RF:

7, 11, 18, 19, 20, 26, 30, 31, 32, 35, 39, 41, and 43.

Thanks again for all your help.

What I ment was a 4 bay UHF style antenna will only be equal in gain to a 2 bay vhf-hi over a small range of vhf-hi channels. If you only had a couple of channels on VHF-hi that you wanted and they were close in frequency to each other a properly sized 4 bay uhf would have just as good of gain as a 2 bay vhf-hi so no need for a seperate 2 bay vhf-hi antenna.

In your case the channel 7 station is much stronger than the ch 11 station so you would want to build one that favors ch11 like a 9 1/2 x 9". About anything in the 9 -10" whisker range will probably work with signals that strong.

One word of caution, the reception area for a 4 bay on vhf-hi is very broad and that could lend itself to multipath issues. If that is an issue the 2 bay vhf-hi may be better even though the gain would be near equal.

Barring multipath problems you should get everything in the green, yellow and maybe pink on your TVFool chart if it's mounted outside in the clear.
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post #1513 of 4798 Old 01-27-2009, 09:34 AM
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Thanks, 11 is presently on RF 57 and will switch to RF 11 at the change over. The antenna (the 9.5 x 9) is in the attic. I couldn’t get RF 57 until they announced that analog 11 went to lower power. They much have increased the power of RF 57 but it would break up some time. Now, with the snow on the roof, 35 breaks up some time so I pointed the antenna a little more west. 35 and all the stations to the south (digital 7 is in the 40s now and will go to RF 7 at the switchover) come in without any problems even with snow on the roof. Analog 7 comes in very clear. Analog 11 came in very clear until I pointed the antenna more west and with to lower power. Analog 11 is a little weaker but still mostly clear. I presently don’t see any problems with multipath on analog 7 for 11 or the analog UHFs.

I just have to wait and see. If need to, I’ll build a 9.5 x 9, with standoffs (like SonicLogic’s ) and see how that works after the switchover.

Thanks again all the help.
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post #1514 of 4798 Old 01-27-2009, 02:51 PM
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Here’s another of my mclapp antennas. This one started out as a 10x9.5 but I later changed the whiskers to 11.5 after the success I had with the longer length. This antenna has a 1x4 for the base which is a piece of treated lumber that came from a shipping pallet. I found it in a dumpster at Lowes.


The standoffs are made from 1.25x1.5 plastic wood. They were cut from a 31” plastic wood baluster (cost $1.35 at Lowes). Plastic wood is very strong and you can torque the screws down tightly without fear of stripping. Notice that on this build I took great care in making sure that the washers did not overlap into the phase lines. I used some wood glue along with a single countersunk screw to fasten the standoffs to the wooden base. The screws that attach the whiskers only touch the plastic wood. They do not go through and touch the treated lumber. This antenna is strong, but it's heavy.
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post #1515 of 4798 Old 01-27-2009, 04:21 PM
 
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What does overlapping the phase lines do to performance???

Also...Why do you call the plastic wood "standoffs"??? They are nothing more than spacers in my opinion...
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post #1516 of 4798 Old 01-27-2009, 05:46 PM
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Originally Posted by Splicer010 View Post

What does overlapping the phase lines do to performance???

It is my understanding that the spacing of the phase lines is an important part of the equation to ensure peak performance. Overlapping the phase lines with the washers will change the frequency response of the antenna. If the phase lines are supposed to be 1.25 apart at all points but sloppy washer placement causes several points along the lines to be closer, antenna gain will be diminished. I will, of course, defer to either mclapp or 300ohm for their expertise. The success of my antenna builds supports the conclusion that washer spacing relative to the phase lines is important.

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Originally Posted by Splicer010 View Post

Also...Why do you call the plastic wood "standoffs"??? They are nothing more than spacers in my opinion...

I used the term standoff rather than spacer because standoff is the correct term to use. The plastic in this case is functioning as a standoff insulator rather than just a mere spacer. The term spacer does not adequately identify the multiple tasks performed.
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post #1517 of 4798 Old 01-27-2009, 05:57 PM
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Quote:
Originally Posted by Splicer010 View Post

What does overlapping the phase lines do to performance???

Also...Why do you call the plastic wood "standoffs"??? They are nothing more than spacers in my opinion...

you want the antenna elements to capture the electromagnetic wave of the tv signal. if the elements capture the wave in a way that adds up in a constructive manner ( the waves are in phase)then you have a stronger signal. similar to having a bathtub full of water and moving your hand back and forth to create a wave, if you can match the wave reflected from the tub the waves will get bigger, if not smaller. so the function of the phasing lines is to put the signals in the antenna in phase and add up.

standoffs are spacers, they hold things at some distance from other objects. sometimes, like with antennas, their dimensions and often that they are insulating is important.
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post #1518 of 4798 Old 01-27-2009, 08:09 PM
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Quote:
Originally Posted by MikeySoft View Post

Thanks, 11 is presently on RF 57 and will switch to RF 11 at the change over. The antenna (the 9.5 x 9) is in the attic. I couldn't get RF 57 until they announced that analog 11 went to lower power. They much have increased the power of RF 57 but it would break up some time. Now, with the snow on the roof, 35 breaks up some time so I pointed the antenna a little more west. 35 and all the stations to the south (digital 7 is in the 40s now and will go to RF 7 at the switchover) come in without any problems even with snow on the roof. Analog 7 comes in very clear. Analog 11 came in very clear until I pointed the antenna more west and with to lower power. Analog 11 is a little weaker but still mostly clear. I presently don't see any problems with multipath on analog 7 for 11 or the analog UHFs.

I just have to wait and see. If need to, I'll build a 9.5 x 9, with standoffs (like SonicLogic's ) and see how that works after the switchover.


Thanks again all the help.

If you get the analog stations watchable now then the digital versions should be fine when they switch (which I see today has been delayed by congress, haven't they got anything better to do) as long as thier power and antenna patterns stay reasonably the same you should be fine.
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post #1519 of 4798 Old 01-27-2009, 08:20 PM
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Baluns... Never though it would get so complicated to understand. Once you get past the act of faith that the 300-75 ohms you buy anywhere is ok for your TV, it gets really confusing.

a) Ok, what the difference between a current balun and a voltage balun?

b) What type (current or voltage) is the common 300-75 (4:1) balun?

c) could a 4:1 current balun be exchanged with a 4:1 voltage balun?

I opened 2 different model of 4:1 balun and looked at the wiring. They are wired the same way. Sorry the pictures aren't clear, I don't have any camera with macro mode.




That's would indicate a standard I guess, but I can't find anything on the net explaining the wiring I saw. No electric schema seems to fit, and I paid attention to the core winding directions too. I actually destroyed it on purpose in the process of making sure I took the wiring right.

d) if you have an official electrical schematic of the common binocular ferrite core 4:1 balun, please give the link!

e) if you have a clue which magnetic field is usually in effect (A or B), please indicate. I believe it's B (maybe with arrows inverted), but if assuming the top 300 ohms pin pushes current while the bottom one pulls current, the field A is the wiring I see. In any case, the 4th coil is surprisingly shorted. (???)

f) Now, I'm still trying to find a 1:1 balun for the clearstream c2 DIY project posted earlier. I have no clue if I need a 1:1 current or voltage balun. Anyone?

g) It looks like I won't find a 1:1 balun in common stores. For the moment I would have to recuperate the the binocular ferrite core of my destroyed balun and make a 1:1 balun myself once I get the plans... Schematic anyone?
LL
LL
LL
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post #1520 of 4798 Old 01-27-2009, 09:19 PM
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SonicLogic,
I ran some really quick computer models of the 11.5" whiskers using the 9.5" spacings and compared it to the 10x9.5" models and it really didn't show much difference on the limited channels I tested. I only ran a few frequencies in the UHF and VHF-hi range and the gains and SWR were very close.

To really do it right I would have to plot more channels and do the calculations for net gain. I tested ch's 18,36,45, and 53 UHF and 7, 10 and 13 vhf-hi.

By not much difference I'm talking a db or less and beam widths and patterns were even quite close as well.
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post #1521 of 4798 Old 01-27-2009, 10:13 PM
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If the phase lines are supposed to be 1.25” apart at all points but sloppy washer placement causes several points along the lines to be closer, antenna gain will be diminished. I will, of course, defer to either mclapp or 300ohm for their expertise.

Yep, sloppy washer placement will mean the phase lines wont be following the model. I generally bend the washer edges a little to get a better grip. Or I use homemade triangle washers using the same metal as the whiskers and phasing lines.

You can reduce the weight of the composite wood standoffs by some more sawing and carving. Not all composite wood is alike. The Monarch brand samples at Lowes have a higher plastic content and less wood flour/chips than those balisters they sell.
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post #1522 of 4798 Old 01-27-2009, 10:20 PM
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It looks like I won't find a 1:1 balun in common stores. For the moment I would have to recuperate the the binocular ferrite core of my destroyed balun and make a 1:1 balun myself once I get the plans... Schematic anyone?

Rather than attempt to duplicate all the info, theres a whole long discussion of that going on in a thread at digitalhome.ca in the Antenna Research & Development subforum.

Your pictures look like most of the baluns Ive taken apart. I did take apart a Gemini one that duplicated the coils by traces on a pcb.
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post #1523 of 4798 Old 01-28-2009, 02:05 PM
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"Macro" Photo Tips: Although my digital camera has a "Macro" (flower icon) setting,
I found it doesn't work anywhere near as well as a NORMAL camera mode shot
with the camera at least 18-inches away and then crop away the excess border.
To post a photo, you'll have to throw away a bunch of hi-rez anyway....

The more light you have, the smaller the aperture, which maximizes the
DEPTH of FIELD. I force the flash to always be ON and sometimes I shoot
outside in bright sunlight with flash ON...extra sunshine helps to fill in shadows....
When using flash, try to avoid straight-on angles to minimize reflections.
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post #1525 of 4798 Old 01-28-2009, 04:53 PM
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Hi, Guys. I Must say, I have been viewing a lot of your projects recently, and it's been conjuring up many great ideas in my own mind regarding anttena construction!

To the guy who built the Mclapp with the ice cube trays, I offer my kudos, regardless what some have said. I must admit, I did have a bit of a chuckle, myself, but I fully understand what you were doing with that idea. In DIY, and in the interest of devising what one might otherwise pay astronomical money for, or for that matter, not be able to obtain commercially, the use of whatever household materials available must be explored. That's what makes all of this so interesting. I thought it was kinda weird, but if it worked, who cares? No one is going to see it that closely way up on your roof, anyway. It's "survival of the slickest," at it's best.- The best part is the cost.

In reference to the guy who had better success using the 11-1/2" whiskers, I, too am interested in Mclapp's findings regarding this. By the way, with the exception of your beige/sand colored shingles, (mine are blue) your roof looks much like mine. I also have multiple antennas, much like yours. Placement nearly identical, too. My Radio Shack Yagi looks a little different than yours, but basically, otherwise, we have the same "motif" on our roofs. My Radio Shack's "Best" antenna, higher up, as yours, won't hold a candle to my Mclapp 9-1/2" x 9" about 10 feet lower!

Anyway, I did a little work today in straightening out my phase lines on my reflectorless DBGH, and as soon as we get some less crummy weather we've been having, I can't wait to hoist that sucker up there! I do have a few concerns regarding it, though.

I noticed on most of the DBGH designs I've seen, that they run the cable line up the back of the mast, attaching a long balun in a way that the leads are back behind everything. My PVC construction incorporated the use of forward facing "stubs" which allowed me to keep the 8 guage phase lines from "flopping around," by attaching them securely to them, in order to maintain a faithful, parallel distance of 2" apart. For this reason, it seemed easiest and best to have the balun attached in front of the antenna and phase lines. Should this affect performance? If this is OK, how far in front of the phase lines should I keep the cable and balun?

While I'm on that subject, I noticed the discussion regarding "sloppy washer placement," and must admit, I'm guilty. All of my 4-bay Mclapp antennas have this issue, and it's just something I guess I overlooked. My best Mclapp, a 9-1/2" whisker X 9" spacing has a 2" spacing on the phase lines, which I used very large brass washers, overlapping significantly. When I measure the spacing, the phase lines are exactly 2" apart, but between the washers, they are about 1-1/2" apart. (All 5 pairs) Is the inconsistency in phase line gap seriously impeding it's abilities? In this situation, which phase line gap would it be following according to modeling? (Actual phase line gap, or the gap between the washers?) In other words, is my antenna acting like an antenna with 2" phase line spacing, 1-1/2" spacing, or neither?

I have some updates regarding the channels I've had trouble with. WBRE, (virtual 28), and WYOU (virtual 22) are coming in rock solid, and are easily the strongest stations.- Both VHF high channels (actual 11 and 13, respectively) For whatever reasons, though, however, channel 28 has occasional, brief periods when there is no signal at all, and wondering if this is the station having problems. (Otherwise, it's my strongest station, which makes no sense.

WVIA, virtual 44, PBS affiliate, a multicast channel has 4 channels: 41.1, 41.2, 41.3, & 41.4. Sometimes, only 41.1 works, and comes in also rock solid, but the others do not at all. When they do come in, they are all equally as strong.

Using the 9-1/2" x 9" Mclapp, I am effectively recieving, with few problems or dropouts, (in order of signal strength) 11, 13, 32, 31, and 41. The problem channels are 49 and 45, with 49 being by far, the least reliable. At times it's fair, and others- nothing. Just wondering what Mclapp version might be optimum for focus on channel 49.1 & 49.2 (actual)- virtual 16 WNEP, (ABC affiliate). There was some discussion regarding getting the VHF high channels with the larger Mclapp, as well as different sizes being more optimum on certain UHF channels, while being a comprimise on others. Using this logic, it seems sensible to build an antenna which strategically focuses more towards the weakest channels, in which mine are actual 49 and 45. (repectively)

By the way, because of my awkward location, between mountains, in a valley, and most stations to the SW, with a few others N/NE and N/NW, it seems to be best in my situation to go reflectorless, which is what I'm doing.

Many thanks for your contributions.

Best Regards,
Eric
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post #1526 of 4798 Old 01-28-2009, 05:47 PM
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May I kindly suggest to anyone wishing to discuss 1-on-1 to use private message, and to bring local reception issues to the forum topics created for that purpose: See
http://www.avsforum.com/avs-vb/forumdisplay.php?f=45
You stand a much better chance of finding peers and getting an answer.

Thank you for preserving the DIY-antenna focus.
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post #1527 of 4798 Old 01-28-2009, 08:52 PM
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Quote:


For this reason, it seemed easiest and best to have the balun attached in front of the antenna and phase lines. Should this affect performance? If this is OK, how far in front of the phase lines should I keep the cable and balun?

When testing, I have the balun in front too. It'll be fine as long as the balun doesnt flop around much. You want it fairly secure.
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post #1528 of 4798 Old 01-28-2009, 09:15 PM
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nepaeric,

The 9.5x9 starts to drop off gain in the upper 40's, as you stated it would be best to build an antenna that is better focused for the problem channels.

Shorter whiskers and phase line vertical spacing's will move the gain curve up in frequency. I would suggest to anyone who has problem channels in the upper 40's to go to a 9x8.5. The 4 bay style antenna gain drops off fast on the upper end and not so much on the lower end so in general it's best to go a little short if you have weak stations in the Channel 40+ range. That size should still catch the upper end of the VHF-hi channels OK as well.

Thanks for the signal reports that helps in the development of these DIY antennas, all the computer modeling doesn't mean a thing if people can't build them and receive some signals. Different antennas react differently to different terrains, elevations, and obstructions and when you put them all together the signal reports help sort some of that out.

Hopefully that was helpful to you and maybe some other forum readers with a similar question.
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post #1529 of 4798 Old 01-28-2009, 09:32 PM
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If I were connecting to an antenna that didn't require impedance matching I might not even bother with a 1:1 balun, especially for reception.

The worse thing that will happen is that the reception pattern may be very slightly skewed, unless the antenna is really unbalanced. If you're transmitting then it can be a problem because the feed line might radiate some RF.

If someone was really worried they could put some ferrite beads on the coax to choke the currents running on the shield. The possible slight gain loss due to the reception pattern skewing without a balun would probably still be less than the balun losses.
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post #1530 of 4798 Old 01-29-2009, 08:20 AM
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mclapp;
On your latest 8 bay stacked - the connection point for the feed line I'm guessing is at the 2" phasing line point. Will you use a 4 x 1 , 1 x1 balun or a direction connection. I'm planning on installing the 40" phasing line about 1"above the other. I'm trying to piece what you are doing from different forums that you frequent and I may miss one or two.
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