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HDTV Technical > The Official AVS Antenna and Related Hardware Topic!
holl_ands's Avatar holl_ands 11:23 AM 06-20-2009
Typo...delete the "s":
http://www.imageevent.com/holl_ands/4bay

I revised the post...I just wanted to make double sure you were using a Hi-VHF rather than a UHF design.
My (no reflector) 4bay webpage is for UHF, where some just happen to work (a little) on Hi-VHF.
And once you add a reflector, it's gonna kill the Hi-VHF capability....unless resized for Hi-VHF.

ProjectSHO89's Avatar ProjectSHO89 11:39 AM 06-20-2009
Quote:
Originally Posted by rbarbier View Post

Ordered the C5 on Thursday. Set to be delivered this Thursday. I'll let you guys know how it works. I know it will be tough to get those channels (7-13) but if the C5 works like it is supposed to, I should get them.

A heads up regarding the UVSJ (diplexer) that is included with the C5:

The plastic case will accommodate either a compression- or crimp-fit F-connector but will not allow the lid to close if you're using a cable with a longer-length factory molded connector or an RG11 compression fitting.

Plan accordingly.


About two weeks ago I was able to get my hands one of the first pre-production C5 antennas.

With an antenna height of only about 12 feet and a good test location (empty lot at NEQ of I-44 at Gray Summit, MO at around 8 AM), I was able to see a near-perfect 8VSB waveform on my Sencore 1474 of KRCG-13 (VHF-12 out of Jefferson City) of more than adequate amplitude to be useful. Distance of about 70 miles with little intervening noise generators. Measured value was approximately -30 dBmV with a C/N ratio of 9.5. Very easily usable with a decent low noise preamp or with some more height.

FCC-predicted signal level was -94 dBm, TV fool for the same spot was -98.1 dBm.
nordloewelabs's Avatar nordloewelabs 11:48 AM 06-20-2009
Quote:
Originally Posted by holl_ands View Post

If you want to try a simple, easily hidden, DIY Hi-VHF antenna that is a step up from
Rabbit Ears, you can start with a Folded Dipole:
www.imageevent.com/holl_ands/yagis

thanks for the links. i checked the "folded dipole" info but it looks a bit too complicated for me (a layman). the other thing is, i dont have the tools to build something that requires such a degree of precision (dimensions and distances depend heavily on wavelength)....

the link below seems to be the less complicated one.
http://www.wfu.edu/~matthews/misc/dipole.html
i might give it a try during the week.

has anyone here tried the Winegard HD-1080? based on the number of times i've asked and the zero feedback i've gotten, i guess that's the most obscure antenna on Winegard's catalog.
IDRick's Avatar IDRick 11:53 AM 06-20-2009
The 1080 is "okay" for UHF. On high vhf, it has large negative gains especially for ch9 and below. There are much better choices if you need high vhf reception.
nordloewelabs's Avatar nordloewelabs 12:02 PM 06-20-2009
Quote:
Originally Posted by IDRick View Post

The 1080 is "okay" for UHF. On high vhf, it has large negative gains especially for ch9 and below. There are much better choices if you need high vhf reception.

yes, i need Hi-VHF. preferably, an antenna that can do UHF too, but it doesnt have to be a great UHF antenna because only Hi-VHF is problematic in my area. UHF comes very easy. how would you compare the HD-1080 to the ones below?

RCA ANT751
CM3010 Stealthtenna
EscapeVelocity's Avatar EscapeVelocity 12:07 PM 06-20-2009
The Winegard HD 1080 isnt particularly good on VHF Hi....certainly no better than Rabbit Ears and probably worse.
nordloewelabs's Avatar nordloewelabs 12:24 PM 06-20-2009
still regarding folded dipoles, is the Terk TV55 (bazooka) a folded dipole? it didnt work for VHF or UHF in my apartment.
EscapeVelocity's Avatar EscapeVelocity 12:44 PM 06-20-2009
Helical Coil, (Helix)
holl_ands's Avatar holl_ands 01:20 PM 06-20-2009
Has anyone seen any specs on either the EZ-HD or the RCA ANT751???
Websites I've checked omit these important little details....

Despite several distractions, I'm still working on the NEC model.
From what I've seen so far, VHF RAW Gain for Ch7 is about 5.5 dB,
rising to 7.5 dB in mid-band and falling some across Ch12-13.

Front-to-Back Ratio is 10+ dB on Ch7, rising to 15+ dB mid-band and
then falling off across Ch12-13 (due to falling forward RAW Gain).

Based on difficulties with YA-1713 model, I expected SWR to be
difficult to model accurately....EZ-HD is no different....maybe it's
a 300-ohm antenna, but I'm seeing much less at VHF freqs....
[Still gotta add the stubs to run UHF curves...]

People should pay close attention to how these "twins" perform on Ch12 & 13....
I hope it's because of a NEC modeling shortcoming.....like the YA-1713 model,
which has a very similar Log-Yagi VHF design....
nordloewelabs's Avatar nordloewelabs 01:57 PM 06-20-2009
Quote:
Originally Posted by holl_ands View Post

Has anyone seen any specs on either the EZ-HD or the RCA ANT751???

here's some info gathered from another post:

Quote:
Originally Posted by schu132 View Post

Sent an email to the site selling the ez-hd antenna and asked about vhf high gain. He replied "The EZ-HD has an average of 7.5 dB gain on VHF. To combine a VHF and UHF use a VHF/UHF signal coupler. This will result in much less signal loss." Does that sound about right? solidsignal has the AntennaCraft Y5-7-13 specs at "Gain VHF: 6.9 dB". Also What's the difference between UVSJ diplexer and a VHF/UHF signal coupler?


IDRick's Avatar IDRick 02:13 PM 06-20-2009
Quote:
Originally Posted by nordloewelabs View Post

yes, i need Hi-VHF. preferably, an antenna that can do UHF too, but it doesnt have to be a great UHF antenna because only Hi-VHF is problematic in my area. UHF comes very easy. how would you compare the HD-1080 to the ones below?

RCA ANT751
CM3010 Stealthtenna

I have personal experience with the EZ HD, similar to ANT751. It works very well for high vhf in my area (ch 8, 9, and 10). It should be noted that we have strong vhf signals (NM's from tvfool were between 50 and 55 dB). The EZ HD or Ant751 would **easily** beat the HD-1080 for high vhf.

Good luck!
EscapeVelocity's Avatar EscapeVelocity 02:15 PM 06-20-2009
Ive got the box and whatever manual or spec sheet manual came with it at home, Ill see if there is any information.

Ive been going with the Winegard 7000R specs as comparable. Here you can see the slight drop off at Channel 13 and also a lower Channel 14, gain spec rising up through the upper UHF television band. The UHF section is nearly identical so I think those specs are probably comparable.....its likely that the RCA ANT751 and EZ HD have slightly better VHF Hi performance....as your modeling would suggest, hollands.

http://www.winegarddirect.com/viewit...p~HD-7000R.htm
nordloewelabs's Avatar nordloewelabs 02:22 PM 06-20-2009
Quote:
Originally Posted by IDRick View Post

The EZ HD or Ant751 would **easily** beat the HD-1080 for high vhf.

does it work well for UHF too?
did you place indoors or outdoors? i can only place antennas indoors.
EscapeVelocity's Avatar EscapeVelocity 02:28 PM 06-20-2009
Quote:
Originally Posted by nordloewelabs View Post

does it work well for UHF too?
did you place indoors or outdoors? i can only place antennas indoors.

Its slightly inferior to the Silver Sensor unamped on UHF, especially on the extreme low end of the UHF television band.

It matches the performance of the "Silver Sensor on UHF" in the VHF Hi band, about 6db gain.

It might be the best solution for you.

The StealthTenna is an interesting choice.....and more aesthetically pleasing. Mount it on the ceiling and call it sculpture for you snooty NY friends.
nordloewelabs's Avatar nordloewelabs 02:32 PM 06-20-2009
Quote:
Originally Posted by EscapeVelocity View Post

The StealthTenna is an interesting choice.....and more aesthetically pleasing. Mount it on the ceiling and call it sculpture for you snooty NY friends.

i would if i had any drilling skills whatsoever!
i'm torn between the ANT751 and the CM3010....
IDRick's Avatar IDRick 02:38 PM 06-20-2009
Quote:
Originally Posted by nordloewelabs View Post

does it work well for UHF too?
did you place indoors or outdoors? i can only place antennas indoors.

It performs reasonably well on UHF. It is better for an urban/suburban environment. No way does it have the 75 mile range claimed by the distributor... Yes, it could work for you indoors, but really depends on your situation. Have you posted your tvfool results? It is an outdoor antenna and not very visually appealing (particularly indoors).

In my case, there was only a small improvement going from the attic to the roof. Margin to dropout increased by 3 to 5 dB, depending on the channel. Which is a nice boost but not the 13 dB occasionally mentioned on this forum.
EscapeVelocity's Avatar EscapeVelocity 03:01 PM 06-20-2009
Quote:
Originally Posted by nordloewelabs View Post

i would if i had any drilling skills whatsoever!
i'm torn between the ANT751 and the CM3010....


Maybe the Discone (aka woman magnet) would really blow your snooty friends away.....post industrialist meso modernist art, relaying the technologization of man and his dystopian dissassociation with his soul/humanity, the breaking of dualist reality into moral and cultural relativism. Or some shennanigans like that.
hphase's Avatar hphase 03:09 PM 06-20-2009
Quote:
Originally Posted by holl_ands View Post

Many stations are upgrading to circular polarization (both Horiz & Vertical) which
means 45-degree antenna has a chance of receiving one, the other or both.
FCC allows stations to DOUBLE their total power if circular polarization....it's
effectively two separate antennas driven by two separate transmitters.....
EACH at the authorized ERP level if it were strictly horizontally polarized
[and I'm sure someone will point out exceptions to this general "rule"...]

Stations can add a vertically-polarized component to their signal as long as the ERP in the vertical polarization does not exceed the licensed ERP in the horizontal polarization. This allows better reception by another linearly polarized antenna with a random orienation (vertical, horizontal, or anything in between.) Adding an equal vertical component requires a doubling of transmitter power, and also doubles the power bill, too.

But, for true circular polarization, there has to be a 90 degree phase shift applied to the vertical component. Circular polarization was originally introduced into analog TV broadcasting to help reduce ghosts. This is because the sense of circular polarization (left- or right-hand) is reversed when the signal reflects off of a building or other obstruction. A circularly polarized antenna will not pick up the refected signal because its polarization is opposite to what it was designed to receive.

When stations add a vertical component to their horizontal component, but don't add the phase shift, that would probably be called "dual polarization," not circular. If the vertical component isn't equal to the horizontal, that would be called elliptical polarization.
nordloewelabs's Avatar nordloewelabs 03:49 PM 06-20-2009
wrong info. disregard this post.
kinemax's Avatar kinemax 03:58 PM 06-20-2009
Quote:
Originally Posted by pjc123 View Post

So, I bought an Antennas Direct DB4 antenna a while back, threw it up in the attic attached to a piece of pvc pipe and aligned it using the signal bars on my tv. Quick......Done. I was getting 8 - 10 bars out of 10 on all UHF digital channels so I was really happy. That combined with NetFlix via a Roku box and goodbye cable. Then the DTV June 12th transition occurred and three channels moved to the upper VHF band (RF channels 7, 11 and 13)... I now get these channels intermittently. So, I am thinking of either adding a small cheap upper VHF antenna (AntennaCraft Y5-7-13 seems highly recommended) or just throwing out the DB4 and putting up something like a Winegard HD7694P. What is the better choice, and is either one acceptable, considering that I want to keep it in the attic for various reasons, and I am trying not to get something that is overkill...

I am in Central NJ (about 35 miles from NYC) and in the same boat: I can't get 13, while 7 & 11 come and go. I tried the DB4-widening (with rod-extension) method suggested by arbie without success. Is augmentation with a Y5-7-13 sufficient or do I need something better like a Y10-7-13 or a YA-1713? Or should I just go for a HD769x and if so which one?

TIA.
EscapeVelocity's Avatar EscapeVelocity 07:47 PM 06-20-2009
Here is an interesting antenna...

Terk TV-35



Quote:


• Due to the compact and durable design, the TERK TV35 will outlast most traditional yagi antennas. No tools required, the TV35 includes everything needed to make it an easy to install antenna.
• Dimensions: 76 7/8” W x 38 1/32” L
• Weight: 2.65lbs.
• Element Type: 10 Elements
• Operational Bandwidth: 54-806MHz
• Gain VHF: 0-4dB
• Gain UHF: 2.5-8.5dB
• Front-to-Back Ratio: 12dB (VHF), 15dB (UHF


pjc123's Avatar pjc123 08:21 PM 06-20-2009
Quote:
Originally Posted by kinemax View Post

I am in Central NJ (about 35 miles from NYC) and in the same boat: I can't get 13, while 7 & 11 come and go. I tried the DB4-widening (with rod-extension) method suggested by arbie without success. Is augmentation with a Y5-7-13 sufficient or do I need something better like a Y10-7-13 or a YA-1713? Or should I just go for a HD769x and if so which one?

TIA.

Thanks for trying the rod extension by the way, since I just don't have the time to fool with it. As a side note, I emailed the following to Winegard with their response attatched:

I need some pre-sales technical help.

I currently have an Antennas Direct DB4 antenna in my attic that works very well (9 to 10 bars out of 10 using my TV's signal meter on all UHF channels). However, New York City just switched 3 stations to the High VHF band after the June 12th transition, so now these stations intermittently come in. So I could just get a VHF only antenna and combine them, but probably just write it off as a loss and just buy a new single VHF/UHF antenna.

Here is my situation:
I need color code yellow and red.
I have 3 High VHF stations (7, 11, and 13)
The rest of the stations are UHF
The mileage is 22 for all the stations.
There are 6 degrees between all broadcasting towers.
MOST IMPORTANTLY I will be installing this in an attic because it is only temporary (I will eventually be moving), so I want to insure I have enough gain to compensate for any loss. The roof material is regular asphalt shingles and I am in a residential area with all ranch style homes and no tall buildings, just a few trees.

I was looking at the HD7694P, but will it compensate for the attic and should I "kick it up a notch"? Also, if I went with a separate VHF antenna instead, what would you recommend? What is the recommend combiner as well?

Thanks


This was the response:

I would suggest the HD7696P antenna to be sure we have enough signal. If you wish to add a VHF antenna then the model YA-1713 would your antenna choice. You will need to find a UHF/ VHF combiner to combine the VHF antenna and UHF antenna with minimum amount of loss.

I also emailed Antennacraft about their Y5-7-13, but never received a response. I like the Antennacraft because it is a reasonable size like the DB4. However, I am reading bad things about Antennacrafts quality from various forums, but in an attic I could care less about wear and tear from the elements.

I am still waiting to hear from someone who has used a specific brand and model with good results, especially in the Central NJ area, before I buy yet another antenna that does not work. I will post anything that I find out.
EscapeVelocity's Avatar EscapeVelocity 10:01 PM 06-20-2009
systems2000's Avatar systems2000 10:38 PM 06-20-2009
Since I get huge amounts of Co-Channel, Adjacent Channel, & Multi-Path interference, I've been thinking of the garbage can solution, but I think the screen solution would be more elegent.

Does anyone know if that would eliminate the problem of using dissimilar antennas causing interference with each other when using a combiner? I'd like to tie several single channel yagi's together (ie. 47 @ 87°, 8 @ 218°, & 32 @ 322° (maybe more)).

I've also been thinking about experimenting with a Primestar dish and retro-fitting it for terrestrial DTV reception. I believe the dish is made of carbon resin and should make for a fine reflector.

On another note, what's the beamwidth of the YA-1713?
finlay648's Avatar finlay648 11:15 PM 06-20-2009
Quote:
Originally Posted by Tower Guy View Post

I'd look at the weakest station that you want to receive. Next, using tvfool, try swapping the two antennas. I'd install the antennas in whichever position gave you the most margin on the weakest station.

I have beenusing 2 CM4228s stacked vertically as my antenna pre-transition but post-transition 9, 11 and 13 went to HI-VHF and I lost reception of 9 and 11. I purchased a YA-1713 to boost reception for 9 and 11. I tried mounting the YA-1713 below the CM4228s (relatively easy to do) but the results were marginally better (9 was better but 11 was about the same). I then lowered the 4228s by a foot and installed the 1713 at the top of the mast with much improved results.

I suppose this means that there is horizontal banding from diffraction and the first location was in a null while the second location was not. I didn't notice any change in the reception of the UHF channels but this makes me wonder if the UHF antennas may be partially in a null. I'm assuming that the size of the bands and their location vary with frequency. Given that the stacked 4228s are about 6' tall, is it likely that there are multiple higher frequency bands spanning the 4228s or am I completely misunderstanding how this works?

I'm thinking that I probably have to redo this setup since seasonal changes will negatively impact it and I'm wondering what are the factors that impact reception the most.

My tvfool info is:

http://www.tvfool.com/?option=com_wr...618ac2e3f7e60d

BTW while looking at the tvfool results for different antnna heights I noticed that reception seemed to get poorer as the height increased above 20' (e.g. to 30' or 40'). That seems counter to what I expected.
ProjectSHO89's Avatar ProjectSHO89 06:24 AM 06-21-2009
Quote:


This was the response:

I would suggest the HD7696P antenna to be sure we have enough signal. If you wish to add a VHF antenna then the model YA-1713 would your antenna choice. You will need to find a UHF/ VHF combiner to combine the VHF antenna and UHF antenna with minimum amount of loss.

Anyone find it ironic that Winegard's tech support suggested adding a big HVHF antenna to one of their own antennas that ALREADY HAS HVHF??? Especially one that has almost as much HVHF gain as doe the YA1713...


The 7694 should do fine. Worst case, go to the 7695.
arxaw's Avatar arxaw 07:03 AM 06-21-2009
Quote:
Originally Posted by finlay648 View Post

...I then lowered the 4228s by a foot and installed the 1713 at the top of the mast with much improved results.

I suppose this means that there is horizontal banding from diffraction and the first location was in a null while the second location was not.....I'm assuming that the size of the bands and their location vary with frequency.

Correct, the bands vary by frequency. VHF may require moving the antenna farther than UHF to find a hot spot.

Interesting article on fringe reception.
PA_MainyYak's Avatar PA_MainyYak 08:33 AM 06-21-2009
Quote:
Originally Posted by EscapeVelocity View Post

I need recs for this situation. Friend of mines, place in the mountains of North Carolina, near Mt. Mitchell.

Old Mill house is metal sheathed.

http://www.tvfool.com/?option=com_wr...7f1480d77d8eb6


Please help!

You might try fine tuning your TV Fool results by using GPS coordinates (easily obtainable thought Google Earth or similar mapping programs). And as mentioned elsewhere, finding a way to raise the antenna higher. At that, reception at the cabin will remain a significant challenge.
kinemax's Avatar kinemax 08:38 AM 06-21-2009
Quote:
Originally Posted by pjc123 View Post

Thanks for trying the rod extension by the way, since I just don't have the time to fool with it.
...

I am not sure I have done the rod-extension method justice, as I have only tried using coat-hanger wires as the extended rods. It seemed to yield a slight increase in signal strength but not enough to form a proper video image, so perhaps some better rod materials might make a critical difference.
Quote:


I am still waiting to hear from someone who has used a specific brand and model with good results, especially in the Central NJ area, before I buy yet another antenna that does not work. I will post anything that I find out.

I just realized that both the 7-13 and 7-69 antenna types would leave out the FM band which I also need, hence I am now looking at the HD708x series (most likely the 7080 since the 7082 or 7084 are probably too big to get in my attic). I also found out that Radio Shack has a VU-90XR for about $65; I am tempted to try it since their VU-110XR which I bought over 15 years ago is doing a wonderful job pulling in all three stations for my other TV on the first floor.
arxaw's Avatar arxaw 09:00 AM 06-21-2009
Quote:
Originally Posted by kinemax View Post

...their VU-110XR which I bought over 15 years ago is doing a wonderful job pulling in all three stations for my other TV on the first floor.

Would it be possible to just split the feed from that antenna to the other TV?
Tags: Channel Master Cm 4228 8 Bay Hdtv Uhf Antenna Cm4228hd
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