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The Official AVS Antenna and Related Hardware Topic! - Page 495

post #14821 of 16104
Well, Walmart does not carry any long range outdoor antennas in their stores, and there are some areas where a short range indoor antenna will just not work. They do offer the CM4228HD online, but they should offer something like a Winegard 7696 or a Clearstream 4 for fringe areas where indoor antennas are not an option.
post #14822 of 16104
Quote:
Originally Posted by OTAhead View Post

Here is the FM FOOL report for KTBZ:

CALL: KTBZ
CHANNEL: 94.5
POWER: 97 KW
Rx (dBm):-76.8
PATH: 2 Edge
DIST:86.4 miles

The FM 6 should easily pick that station all by itself going by this contour map. My FM 6 could easily get stations well outside the contour that don't even show up on the FM Fool chart. This station was one I listened to frequently when I lived in Manassas which is completely off the map about 30 miles outside the fringe contour.
post #14823 of 16104
Quote:


I originally used the layout here - http://www.centralmediaserver.com/WI...nnadrawing.pdf

Thats the original SBGH gen1 with a mesh reflector. The pvc frame for it, designed by the guy at channel 9, is way overkill. There are simpler frame methods that are just as strong and lighter and cheaper.

Yeah, if youre going to build a rod model, the "gold standard" GH6 model by JED looks good for you. http://www.jedsoft.org/fun/antennas/dtv/gh.html

(Youll most likely get that strong channel 11 even without NARODs. If need be, you could always attach a pair of straight 28" NARODs to that GH6 model. Thats an important advantage the rod models have over the mesh models. The mesh models are strictly uhf only.)

I take it youll be aiming at 233 degrees true, which means you have some big hills between you and the station. I would tilt the antenna upwards to point to the tops of those hills.
post #14824 of 16104
I used his dimensions for the elements only (I printed his layout and bent the elements to match). I epoxied the element inner corners to a scrap board, made two standoffs and used some strapping to hold the mesh screen. For the roof build I was thinking PVC and fiberglass rods similar to a build of yours I've seen.
post #14825 of 16104
Quote:
Originally Posted by Digital Rules View Post

The FM 6 should easily pick that station all by itself going by this contour map. My FM 6 could easily get stations well outside the contour that don't even show up on the FM Fool chart. This station was one I listened to frequently when I lived in Manassas which is completely off the map about 30 miles outside the fringe contour.

Well, I never would have thunk to tell the truth. If I ever have occasion to take the antenna down for any reason I will remove the 7777 and try it without it.

The FM6 seems to be a pretty good little antenna.

And thanks for the coverage map. The web site is going on one of my Droids home pages for future reference.

Thanks again.
post #14826 of 16104
It has been some time since I last posted. I am now thinking about goback to OTA HDTV again. Comcast prices including internet is getting ridiculousness. I watch maybe 10 channels out of over 300. These are the channels I need to receive. Back in the day for an attic install the CM 4228 used to be the antenna of choice. Is it still or is there a new kid on the block these days? Thanks,Rick

KYW-DT 3.1 CBS
RF Channel: 26
59 miles at 18°
UHF
Violet
WCAU-DT 10.1 NBC
RF Channel: 34
59 miles at 18°
UHF
Violet
WPHL-DT 17.1 MNT
RF Channel: 17
59 miles at 18°
UHF
Violet
WPSG-DT 57.1 CW
RF Channel: 32
59 miles at 18°
UHF
Violet
WPVI-DT 6.1 ABC
RF Channel: 6
59 miles at 18°
VHF
Violet
WYBE-DT 35.1 PBS
RF Channel: 35
59 miles at 18°
UHF
Violet
post #14827 of 16104
Quote:
Originally Posted by smaerd58 View Post

It has been some time since I last posted. I am now thinking about goback to OTA HDTV again. Comcast prices including internet is getting ridiculousness. I watch maybe 10 channels out of over 300. These are the channels I need to receive. Back in the day for an attic install the CM 4228 used to be the antenna of choice. Is it still or is there a new kid on the block these days? Thanks,Rick

KYW-DT 3.1 CBS
RF Channel: 26
59 miles at 18°
UHF
Violet
WCAU-DT 10.1 NBC
RF Channel: 34
59 miles at 18°
UHF
Violet
WPHL-DT 17.1 MNT
RF Channel: 17
59 miles at 18°
UHF
Violet
WPSG-DT 57.1 CW
RF Channel: 32
59 miles at 18°
UHF
Violet
WPVI-DT 6.1 ABC
RF Channel: 6
59 miles at 18°
VHF
Violet
WYBE-DT 35.1 PBS
RF Channel: 35
59 miles at 18°
UHF
Violet

Please post a TVfool report. http://www.tvfool.com/?option=com_wrapper&Itemid=29
post #14828 of 16104
The 4228 should be good for all the Philadelphia UHF channels, but may not do the job for ABC on RF6 at 59 miles. A separate VHF antenna may be required. Plus a preamp. But you may stand a chance at ABC from Baltimore which is UHF, but not sure of the distance at your location. And you're probably a bit too far for DC channels.
post #14829 of 16104
Quote:
Originally Posted by smaerd58 View Post

Back in the day for an attic install the CM 4228 used to be the antenna of choice.

You need a high gain antenna that covers low band VHF, high band VHF and UHF. I doubt that any antenna will work for you in the attic.

Take a look at the Winegard HD 7084P with AP8700 preamp. Other similar antennas and preamps are also appropriate.
post #14830 of 16104
Ironic I was just there earlier ;-) I am only looking for digitals.
Here is my link

http://www.tvfool.com/?option=com_wr...de65f129c3d6be

Back in 06 with a cheap RS UHF-Only Model: U-75R mounted in Attic and is still up there but not hooked up because Comcast cut the cable and used my RG6 to run theres. I got these results.

KYW-DT 3.1 80%
WPVI-DT 6.1,6.2,6.3 0%
WCAU 10-01 70%
WXPL 10-02 70%
WGTW 48-01,02,03,04,05 70%
WPSG 57-01


Thanks,Rick
post #14831 of 16104
Quote:
Originally Posted by Tower Guy View Post

You need a high gain antenna that covers low band VHF, high band VHF and UHF. I doubt that any antenna will work for you in the attic.

Take a look at the Winegard HD 7084P with AP8700 preamp. Other similar antennas and preamps are also appropriate.

I really like my Channel Master 3671 antenna...
post #14832 of 16104
Quote:
No offense on your product but for practically free I can make an antenna that will get 8 dB on UHF.

Then you're obviously not a candidate for a small, compact antenna (that doesn't look like remodeled coat hangers) that can be purchased in a retail store, eh?

Quote:
An antenna like that that would have that 15-17 dB gain on channels 15-27 is one I would consider getting.

As Scooby Doo would say, "Rotsa Ruck" on finding that one... Do you have an idea of the physical size required for that much gain at those frequencies. Then, you'd still have to commercialize it for sale to a very, very small niche of customers. Then you'd have to figure out what to charge for it so you don't go broke making something that's large, expensive, and you only sell a relative handful of them. Decisions, decisions....


Regards!
post #14833 of 16104
Quote:
Back in the day for an attic install the CM 4228 used to be the antenna of choice.

Quote:
Back in 06 with a cheap RS UHF-Only Model: U-75R mounted in Attic I got these results.

Are you north of the WDSD FM transmitting towers ? Because if that 50 KW transmitter is in your signal path, youll have a hard time getting RF 6 consistently.

Back in 2006, which was during the transition, all those digital channels were in the uhf channel 60's range, so you really cant do a useful comparison now.

You lose a lot of signal in an attic, from 6 to 24+ db. I would mount the CM4228 and the U-75R outdoors and combine the two with a UVSJ. If the cable length is over 30 ft, use a QUALITY preamp, like from Channel Master or Winegard. Avoid the Rat Shack ones.
post #14834 of 16104
Quote:
Originally Posted by ADTech View Post

Then you're obviously not a candidate for a small, compact antenna (that doesn't look like remodeled coat hangers) that can be purchased in a retail store, eh?

I just have a thing about selling someone something for $70 they can make for $5 that works equally well or better. call me silly.


Quote:
As Scooby Doo would say, "Rotsa Ruck" on finding that one... Do you have an idea of the physical size required for that much gain at those frequencies.

Let's see to move the gain that's at 698 MHz down to 554 MHz? yeah about 25% larger.

Quote:
Then, you'd still have to commercialize it for sale to a very, very small niche of customers. Then you'd have to figure out what to charge for it so you don't go broke making something that's large, expensive, and you only sell a relative handful of them. Decisions, decisions....

Just wishing out loud. No need to be a "donkey" about it. I never suggested you make such a thing. Quit getting defensive. Gee I even said it was a nice antenna and you go off and be as smart aleck. You just made sure I never buy anything form AD. Good job.
post #14835 of 16104
And you can make a cup of coffee at home for 25 cents or less but people still line up at Starbucks! There's a customer for almost every product and service on the market. Isn't capitalism grand?

If using the 91XG as a comparison, you'd actually have to scale its peak gain from 765 MHz, it's current peak, down to the 554 MHz making it about 35-40% larger then the existing model. The alternative to a Yagi-style antenna would probably be either a multi-bay bowtie or a parabolic. For example, you could rescale our new DB4e up by 25%, then make a two unit horizontal stack making a total estimated dimension of about 5' wide by 4' tall by 7-8" deep. Theoretically, that should put you in a the ballpark with a peak gain around 16-17 dBi at the top of the design band.

Sorry, it wasn't my intention to rub you the wrong way. I was just pointing out the business complications that are involved in any new product that would have to be considered. We'd love to have the perfect antenna for everyone, but the business doesn't permit that.

Cheers!
post #14836 of 16104
Walmart won't carry a huge antenna, due to shelf space vs profit. Plus, their very liberal return policy would have them taking back antennas that have a high probability of damage. This is what a walmart corporate employee told me, in Bentonville, Ark., where WM headquarters are.
post #14837 of 16104
Quote:
Originally Posted by arxaw View Post

Walmart won't carry a huge antenna, due to shelf space vs profit. Plus, their very liberal return policy would have them taking back antennas that have a high probability of damage. This is what a walmart corporate employee told me, in Bentonville, Ark., where WM headquarters are.

Well, back in the analog days, Walmart, Kmart, and Sears all carried the large outside antennas. Not anymore. And Lowes use to carry Channel Master. Now they only have some RCA or Philips brand.
post #14838 of 16104
Quote:


Well, back in the analog days, Walmart, Kmart, and Sears all carried the large outside antennas. Not anymore. And Lowes use to carry Channel Master. Now they only have some RCA or Philips brand.

Yep, and in the old days they used to display those large antennas by hanging them from the ceiling, taking up absolutely NO shelf space.

Maybe the cable companies are paying the chains to sell only antennas that wont work well in an area ??????
post #14839 of 16104
Quote:
Originally Posted by tylerSC View Post

Well, back in the analog days, Walmart, Kmart, and Sears all carried the large outside antennas. Not anymore. And Lowes use to carry Channel Master. Now they only have some RCA or Philips brand.

And to think how much floor space was taken up with those big, bulky, console color TVs...
post #14840 of 16104
Quote:
Originally Posted by BCF68 View Post

I just have a thing about selling someone something for $70 they can make for $5 that works equally well or better. call me silly.

Gain isn't everything. Front-to-Rear is another important antenna spec and I've seen the F/R plots on those homemade antennas and they aren't very good. Some of us live in places where F/R is the most important spec. The 91XG seems to be tops in that department and has been able to receive stations up here in the foothills when others couldn't. I tried others and they didn't work as well.

I've attached an image showing my situation. I'm located at the red dot on the right. KOVR is representative of my local stations to the west. The blue line shows the 2 edge path to my antennas. The red lines show the LOS path to a range of higher mountains 6 miles east of me and the green lines the reflections to the rear of my antennas.

In this situation the reflections are nearly as strong as the signals on the main path. I'm entirely dependent on the F/R of the antennas to be able to receive my local stations.

The 2nd image shows the spectrum analyzer trace for the direct path of KOVR and the reflections when pointed 180 degrees. It's a tough situation for any antenna.
LL
LL
post #14841 of 16104
Quote:
Originally Posted by Calaveras View Post

I've attached an image showing my situation. I'm located at the red dot on the right. KOVR is representative of my local stations to the west. The blue line shows the 2 edge path to my antennas. The red lines show the LOS path to a range of higher mountains 6 miles east of me and the green lines the reflections to the rear of my antennas.

I never realized that you were stuck that low behind the hill to the west of you. How far north and south does that ridge run? Considering your location, your antennas do a great job for you!

Now I see why you have a better shot at Salinas than you do at Walnut Grove.

Larry
post #14842 of 16104
Quote:
Originally Posted by Calaveras View Post

Gain isn't everything. Front-to-Rear is another important antenna spec and I've seen the F/R plots on those homemade antennas and they aren't very good. Some of us live in places where F/R is the most important spec.

If you use a reflector it will reject those signals from the back. Unless you want to tell hollands his models are full of crap. I think he'd disagree with you.
post #14843 of 16104
WDSD tower is south of me I live near Garrisons Lake. I repaired the old RS antenna and I get all Phily channels on UHF at 75% or better except for channel 6 VHF. Would like to find a small form factor VHF for the attic to grab that one. Also at the time my run is about 50 ft. No preamp. Thanks, Rick
post #14844 of 16104
Quote:
Originally Posted by BCF68 View Post

If you use a reflector it will reject those signals from the back. Unless you want to tell hollands his models are full of crap. I think he'd disagree with you.

Of course, all gain in a directional antenna comes from "narrowing" the beam width. I am not enough of a math guy to calculate what the theoretical maximum gain would be with a very narrow beam width. The higher the gain, the more difficult to "aim".

If I remember correctly, the simple dipole antenna is 2-3 db gain because off the ends is very weak.
post #14845 of 16104
Quote:
Originally Posted by BCF68 View Post

If you use a reflector it will reject those signals from the back. Unless you want to tell hollands his models are full of crap. I think he'd disagree with you.

Can you provide links to real world tests with spectrum analyzer displays showing the F/R? The models I was looking at for the Gray-Hoverman antenna with screen show the F/R to be about equal to slightly worse than the model for the 91XG.

I tried increasing the screen size on the 91XGs I have up and it made no improvement on the F/R at all.

I had some experience recently building an antenna from a model and I found that the real antenna and the model don't necessarily perform exactly the same. Models have their limitations. Don't get me wrong. I'm not saying they are useless but there are real world factors like position of baluns, feed line, hardware used to build the antenna, masts, other nearby antennas, element length and spacing errors, etc. that can alter the performance that are not part of the models in most cases. And these things never enhance the antenna performance.

I've attached a spectrum analyzer trace of KMMW 28 which is one of my few LOS stations. The F/B averages around 28 dB but you can still see that I'm receiving reflections from the hills because the back trace is so choppy.

Chuck
LL
post #14846 of 16104
Quote:
Originally Posted by Larry Kenney View Post

I never realized that you were stuck that low behind the hill to the west of you. How far north and south does that ridge run? Considering your location, your antennas do a great job for you!

Now I see why you have a better shot at Salinas than you do at Walnut Grove.

Larry

That close-in ridge begins to block me at about 245 degrees and goes up and down as you move north. It's really bad toward the City of Sacramento. Sutro is at 253 degrees but the Fremont transmitters are at 235 in the clear and Salinas is at 208 degrees, really clear.

Of course those terrain plots greatly exaggerate the refraction angles because the horizontal distances are very compressed. The angles to Walnut Grove are less than 0.5 degrees.

I attached the terrain plots for KGO and KSBW. You can see why Sutro is so hard from here where KSBW has just one edge fairly close to their transmitter. I added in transmit and receive antenna heights which is why my added blue line is higher at the end points. I'm on the left in these plots.

Chuck
LL
LL
post #14847 of 16104
Quote:
Originally Posted by niualaals94 View Post

I haven't read this entire thread so please forgive me, but many times on this forum I have seen folks send a link to a web site, where you plug in your zip code and it will tell you the HD channels you should be able to receive and the best type of antenna for receiving them. Does anyone know that link? Thanks!

I think TV Fool is mentioned most often. And another (I think older) site is AntennaWeb.

P.S. There was some kind of .JPG link appended to your post as an IMG. I can't even see it, so the link may be bad, but is it really necessary?
post #14848 of 16104
niualaals94,
Use the address entry form at TVFool:
http://www.tvfool.com/?option=com_wrapper&Itemid=29
If you live in a rural area, use the mapping tool:
http://www.tvfool.com/?option=com_wrapper&Itemid=29
Find your house and drag-drop the red map marker onto it, for the most accurate results.

You may get a long list of channels. Only the stronger ones at the top of the list will be receivable. See the color code key at the bottom of the results page.
post #14849 of 16104
Quote:
Originally Posted by Calaveras View Post

I've attached a spectrum analyzer trace of KMMW 28 which is one of my few LOS stations. The F/B averages around 28 dB but you can still see that I'm receiving reflections from the hills because the back trace is so choppy.

Chuck

Short of making a reflector out of lead ( which isn't practical ) no reflector is going to block all of a signal from behind. That being said 28 dB is 99.8% which I think is pretty good.
post #14850 of 16104
Quote:
Originally Posted by smaerd58 View Post

Ironic I was just there earlier ;-) I am only looking for digitals.
Here is my link

http://www.tvfool.com/?option=com_wr...de65f129c3d6be

Back in 06 with a cheap RS UHF-Only Model: U-75R mounted in Attic and is still up there but not hooked up because Comcast cut the cable and used my RG6 to run theres. I got these results.

KYW-DT 3.1 80%
WPVI-DT 6.1,6.2,6.3 0%
WCAU 10-01 70%
WXPL 10-02 70%
WGTW 48-01,02,03,04,05 70%
WPSG 57-01


Thanks,Rick

According to that TVFool report, you should also have a decent shot at most Baltimore channels at 54 miles. And ABC from Baltimore may be easier to receive as WMAR is on UHF, and the Philly ABC on RF6 is reportedly problematic. But DC is probably just a bit too far at 82 miles, although their RF7 and RF9 are more powerful than many VHFs in other markets, so if you had a very good outside set up, you just might be able to see them at times. Not sure about WTTG and WRC which are Fox and NBC on UHF, but it would be nice to get them as they are major network O & O affiliates from the nation's capitol.
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