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Discussion Starter #1
First, i've been reading the OTA forum for the past couple months, anxious to attempt my first antenna build. I purchased a MANT901 hdtv antenna with 51 elements couple years ago. it claims 140 mile VHF and 80 mile UHF. its performance was ok, however i would experience occasional drops. channels were 6.1,6.2,and 6.3. 13.1-13.4 are hi VHF and would also get these. last week i replaced this with and older style yagi. i lost the hi vhf, but gained 4.1, 11.1 and 11.2, 19.3 and 49. however they only came in on crystal clear days/nights.

Secondly, i really want to build the SBGH NAROD. will this be sufficient? i have several older vhf antennas to utilize for parts. one i have removed the aluminum phasing lines, constructed a jig and made the hoverman elements and the NARODS. i'm hoping to use the reflectors and the 1 inch square tubing for the framing.

any help would be appreciated. thanks so much. i like the site and forum.

here is my TVFOOL; 300ohm maybe you have an idea for me.

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id=da32807aba542f
 

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SBGH for Veblen South Dakota

Wow, thats some very weak signals, from varied directions. Youre going to need a rotor. And a separate VHF-Low antenna for channel 3 combining it to the SBGH or DBGH with a HLSJ.
I think youre going to need a DoubleBayGH with NARODs for your uhf/vhf-hi stations, but I would build the SingleBayGH with NARODs first and see what you can get. Then add the second bay and phasing lines.

Have you had some success with other commercial antennas ? Post your experiences with those.
 

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Discussion Starter #3
low signals

i first used an antenna similar to to the winegard PR 7037, it worked fine for the the digital transition for some channels. i probably was suckered, along with many, the marketing campaign, to purchase new HDTv antennas. oh well. Hence the Philips Mant901, they claimed 140 mi VHF and 80 mile UHF. I'm not sure what u call the UHF antenna im using now, your basic UHF you can probably get a radio shack. we have this huge winter storm now, from my loaction to fargo, ND is a blizzard. I'm getting 6.1, 6.2, 6.3 and 19.3 on a signal meter on my hdtv 1-10 bars, it shows a 3.
by the way what is HLSJ? topography to my north is flat, to my south is a ridge of hills that run about 150 miles, starting 3 miles west, SW, S, the rise is about 500 ft or more, im guessing. so not sure if i can pick up the low vhf.
 

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charging said:
i apologize for being unfamiliar on how to reply to the posts. when i do, i am not sure where they go? will they show in the antenna link that u sent me?
thanx
btw, what is HLSV?

i first used an antenna similar to to the winegard PR 7037, it worked fine for the the digital transition for some channels. i probably was suckered, along with many the marketing campaign, to purchase new HDTv antennas. oh well. Hence the Philips Mant901, they claimed 140 mi VHF and 80 mile UHF. I'm not sure what u call the UHF antenna im using now, your basic UHF u can probably get a radio shack. we have this huge winter storm now, from my loaction to fargo is a blizzard. I'm getting 6.1, 6.2, 6.3 and 19.3 on a signal meter from my hdtv 1-10 bars, it shows a 3.
by the way what is HLSJ? topography to my north is flat, to my south is a ridge of hills that run about 150 miles, starting 3 miles west, SW, S, the rise is about 500 ft or more, im guessing. so not sure if i can pick up the low vhf.
Yes, they will go in that link, so reply in there, its much easier and others can help too. Ill put this reply in there also. http://www.digitalhome.ca/forum/showthread.php?t=134435

A HLSJ is a Vhf High and Low Signal Joiner.
 

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topography to my north is flat, to my south is a ridge of hills that run about 150 miles, starting 3 miles west, SW, S, the rise is about 500 ft or more, im guessing. so not sure if i can pick up the low vhf.
Real channel 3 is your strongest signal, and Vhf-low signals do hug closer to the ground than the higher channels (better for hilly terrain), so Im guessing you should be able to receive it. But youll need a decent Vhf-low antenna to get it. Im surprised you dont get it now with the Mant 901, as it should be strong for channel 3.
The SBGH/DBGHs are uhf only antennas.
The SBGH/DBGHs are uhf and vhf-hi combo antennas.
Thats why youll need a vhf-low and a HLSJ to use with one of them.

Vhf-low antennas are large. A half wavelength for your channel 3 is around 93.7 inches.
Uhf antennas are much much smaller. For your channel 19 (15.1) Fox, a half wavelength is around 11.8 inches.

i probably was suckered, along with many the marketing campaign, to purchase new HDTv antennas. oh well.
But did you check to see if the antenna was backwards compatible for B/W TV ????
And if they ever do 3D over those same channels, Im sure those antennas will be repackaged into a different box, heh.

Yep, digital or analog, the antennas needed for channels 2 to 51 are exactly the same. The only thing that changed is that they took away channels 52 to 69 (and 70 to 83 before that). Very few commercial antennas have been optimized or improved for channels 2 to 51 over their channel 2 to 69 counterparts.
 

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Discussion Starter #6
300ohm,

a break from snow removal and weather, back to my project. I think for my situation, a GH with NARODS and Narod reflectors to capture the high vhf should work for me. should be able to capture the PBS stations from my tvfool. can i stack a low vhf anteena at the top of the SBGH? ty
 

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Discussion Starter #8
300,

i cant find your sticky for the genI/genII plans. btw, can i go gapless for my build project?

charging
 

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300,

i cant find your sticky for the genI/genII plans. btw, can i go gapless for my build project?
You can, but you lose almost a db in gain on the mesh models by not having that vertical split down the middle. Cutting out that vertical split in the middle is best done when the antenna is finished, and everything is tightened up. :)

The thread is here : http://www.digitalhome.ca/forum/showthread.php?t=95898&page=5
Look at the picture in post #63 for a better, cheaper way of making the stub holders than is shown in the parts list.
 

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Discussion Starter #12
300ohm,

now, all things cosidered...what about a preamp? since i am deep fringe? right? i dont have a pre amp with my current configuration, which is a uhf arrow type antenna. however i am using a amplifier.

pre amp with my first build sbgh w/narod and narod reflector and amplifier. thats what i am considering.

thanx again
 

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Yeah, a quality preamp is better than a quality distribution amp because youre amplifying before the signal goes down the coax run. Youre in no danger of overloading, (unless you have a very strong FM radio station nearby, check FMFool) so a high powered CM7777 would be nice. :p
 

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charging, if you go to the top level of the OTA Forum you'll find discussion threads covering everything you need to know about preamps and just about any other type of OTA gear available. We'll keep this current thread focused on your GH antenna needs. :)
 

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Discussion Starter #15
Stampeder,

much appreciated.

300ohm,

ther nearest Fm Tower seems to be about 18 miles from my location. now to search for that cm7777.

charging
 

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Discussion Starter #16
Update!

I finally finished my SBGH. Have a couple glitches with the build, hence it is partially complete. However, i have some fairly good news with what i have.
1.) It works! i tested 2 locations 1.5 miles apart, both indoors. i can only anticipate the performance on the roof.
2.) i do not have the NAROD's mounted 10 inches behind yet.(hopefully tomorrow)
3.) erroneous measurment put my elements 13mm shy in front of the reflectors. i am at 87mm instead of 105mm.
4.) i do not have a pre-amp yet, using a multimedia drop amp.( forward path 54-1000mhz +18bd; return 5-42mhz -1db).
5.) my rooftop mounted mant901 right now is not pulling channels 4.1 and 11.1, 11.2. my SBGH standing in my living room IS! remember i am in the FRINGE! but no VHF. hopefully with the reflectors 10inch back and mounted on the roof.( im getting 4.1(20%strength), 6.1, 6.2, 6.3(80%), 11.1, 11.2(20%) .

So, just to give you guys a brief update. I am satisfied thus far. when I make my corrections and fully expand to DBGH...

parts list: 78'' boom from old antenna, reflectors from old antenna fabricated to specs, element lines from old antenna shaped from jig, used 300-75ohm, scrap 1/4" plexiglass fabbed to element, old fiberglass tent poles fabbed and tapped to support elements. all FREE. the only thing i purchased was a few nuts and bolts.

charging

btw, couple guys driving around stopped by to ask about my mant901 rooftop antenna to ask if it works, came in and were impressed with what i was getting. I showed them my SBGH build. i think there gonna try and build there own.
 

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5.) my rooftop mounted mant901 right now is not pulling channels 4.1 and 11.1, 11.2. my SBGH standing in my living room IS! remember i am in the FRINGE!
Yeah, it is amazing and fantastic that you are pulling in -12.7NM and -19.5NM signals, thats like super super fringe. As far as I can tell from the tropo forecast, no tropo is occuring either. You must also have a good tuner.
Oddly due to local variations, in low signal locations like yours, the living room may be the better hot spot, so dont get your hopes up yet on the rooftop mount.
The lack of ANY strong signals in your area seems to be a plus for getting the low NM signals.

btw, couple guys driving around stopped by to ask about my mant901 rooftop antenna
From what Ive read about the mant901, customer feedback and such, it seems to be a huge disappointment.
Looking at the uhf section on it, it looks to me like it would be about a 13 dBi uhf antenna, only a little below a SBGH. But it seems to perform more like a 10dBi antenna in real life from what Ive read.
Its vee boom vhf section, which looks a lot like my CM1221, looks to have performance far far below it, also from what Ive read.
Something seems drastically wrong with the design or manufacture (or maybe customer setup) of the mant901.
 

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Discussion Starter #18
300ohm,

were surprised at all about the 87mm distance between element to reflector? i forgot to mention i lost FOX ch15.1, 19.3 on the SBGH. the mant901 does get this...on a rare occasions(probably tropo gets the 4.1, 11.1 and .2.)
hope to get some pictures up so the community can visulize my setup. i agree about the hotspot in my living room, but will continue to"play" around. also i really hope to tune my PBS stations(vhf)

charging
 

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300ohm,

were surprised at all about the 87mm distance between element to reflector? i forgot to mention i lost FOX ch15.1, 19.3 on the SBGH.
The shorter element to reflector distance helps the higher uhf channels and hurts the lower uhf channels. Do you still get channel 3 ?

Another positive you have going for you are the soils of the mid-west. From what Ive read, they seem to be about the best for long range TV reception. :)
 

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Discussion Starter #20
I never did get my channel 3. but it seems SBGH is more directional; for 15.1(fox). yea also virtually flat terrain to my north. going to do some tweaking this afternoon.

Will increasing my NAROD to 3/8 dia reflector help with my vhf?

charging
 
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