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EV's Recommended & Top Rated DTV Indoor UHF/VHF Set Top Antenna Review Round-Up Guide - Page 55

post #1621 of 3314
Thread Starter 
Here is a video produced by AVSforum member jwwm_2, of the improved design of the 4 bay advanced and tested by AVSforum mclapp on the How to build a UHF antenna thread. This desian uses wider spacing and longer elements to increase gain in the heart of the newly shrunken TV UHF band spectrum, and also has gain on UHF High. Much improved version of the 4 bay bowtie. There is a great comparison between this design and the famous Youtube Coathanger Antenna right at the beginning.

A Better HDTV Antenna
post #1622 of 3314
Thread Starter 
RCA ANT751 on the way.




post #1623 of 3314
I have been using this RCA ANT 1400 Flat Panel Antenna for about 4 months now. I am very happy with the results from it.

I live in an 6 floor apartment building on the 2 nd floor and there are a lot of tall buildings around me. I feed the out of the antenna into a 25 db amp and i get 12 digital stations with it just laying in the window.

I have not moved it around to see if i could get more channels yet ( read lazy here ) !

It gets HD signal that is 25.5 miles away down in this concrete hole i am in. I think that is pretty good. I am trying to design a way to mount a high gain out door antenna on a stand near my apt. window with a rotor and see if there is any improvement !

So i would give the RCA ANT 1400 a 8.5 out of 10 stars.
post #1624 of 3314
hello, I am a beginner and have just started testing antennas in order to see if we can drop Comcast. In the last month I have tried 3 antennas: an Artec antenna from meritline that came bundled with my converter for $4, the $12 1874 budget antenna from Radio Shack and the $50 Radio Shack amplified UFO antenna. After hearing such rave reviews about the UFO, and playing with it for a few days, I can honestly say I cannot tell the difference between this antenna and the other 2, I seem to get the same amount of channels. In fact, when i turn off the amplification on the UFO the fringe channels look about the same as when the amplification is on. I know that there is an elevation problem that is keeping me away from a perfect picture of the channel I want.

My question is I keep hearing people saying how signal went from 70 to 90%, how exactly do you measure that? And would it be better to keep the more expensive antennas because they are less likely to pixelate in bad weather or some other reason that is obscure to me, or is this just a YMMV type of situation where its okay to keep the cheaper one. I am so disappointed, had such high hopes for the UFO.
post #1625 of 3314
Thread Starter 
Post a link to your TVfool. And tell us what stations you are getting with the antennas. Which one you are trying to get. And where you are located....in a basement, condo, house, etc. What is this elevation thing you are on about?

The short answer is that sometimes the basic RE&Loop is the best antenna solution for some people.

The TVfool will tell us a lot.
post #1626 of 3314
Thread Starter 
Great CECB test data and other information.

Hat Tip Holl_ands.

Quote:
Also note that NAB/MSTV tasked MSW (Meintel, Sgrignoli & Wallace) to perform
Lab Tests on a number of CECBs to verify that they met NTIA requirements:
http://www.nabfastroad.org/NAB-STV%2...y-report1.html
Also note User Guides for 20 CECBs....and interior photos in the Summary Report.
post #1627 of 3314
This is what my TV fool looks like

i had posted before and got recommended the UFO antenna. I am able to receive really well all the yellow channels, but nothing else. I really would like to get KUNS, the analog of which comes in snowy. The UFO antenna did not make any difference, whether amplified or not, worked as well as the other artec meritline $4 antenna and the 1874 radio shack budget antenna. So I am pretty disappointed.

The reason i cant get KUNS is that I am a tad lower in elevation than my neighbors between me and the tower, but since I can get so much of the signal, I kind of expected better from the UFO. I guess now I am just accepting i might have to live without this channel, so dont know if there is a reason to keep the UFO thing. I hate I need to plug it in.
post #1628 of 3314
Thread Starter 
Oh, I remember you. Sorry.

Did you try moving the antenna around to find a sweet spot, especially if you have obstructions warping the em radiation patterns? Over by the window. Stick it out the window and see if that helps.....never can tell what building materials you or your neighbor have that might be monkeying up the signals.


And just to make sure, you did spin the UHF elements around in the disc right. position 1 is just to the left of 12 oclock and position 12 is at 12 oclock when facing the front of the unit looking down on it. So you can set it to 12 and then point the back of the unit towards the 140 degrees SouthEast.
post #1629 of 3314
Quote:
Originally Posted by haydeecm View Post

This is what my TV fool looks like

i had posted before and got recommended the UFO antenna. I am able to receive really well all the yellow channels, but nothing else. I really would like to get KUNS, the analog of which comes in snowy. The UFO antenna did not make any difference, whether amplified or not, worked as well as the other artec meritline $4 antenna and the 1874 radio shack budget antenna. So I am pretty disappointed.

The reason i cant get KUNS is that I am a tad lower in elevation than my neighbors between me and the tower, but since I can get so much of the signal, I kind of expected better from the UFO. I guess now I am just accepting i might have to live without this channel, so dont know if there is a reason to keep the UFO thing. I hate I need to plug it in.

KUNS is also in an opposite direction from most of the channels you probably are getting. So you'll probably need to tune to it manually whenever you want to watch it. I agree with EV - double-check that it's set up properly. ALso, where is it? The attic? The higher you can put it, the better you'll be.

As for the other antennas, did you try tuning them to KUNS first? In other words, use a compass and make sure the antenna's pointing 123 degrees (UHF element is perpendicular to your compass direction).

Have you tried an amplifier? Picking up a CM-7777 might help resolve the issue as well...
post #1630 of 3314
I dont think i need to manually tune anything, since I can pick up the channels from Seattle no matter what position I put the antennas, I think the signals are pretty good from there, so I only care about KUNS right now. I have played with the settings and pointed it and it seems to get better, but signal never gets good enough to pick up the digital signal, but I find the analog half-watchable. But I do agree if I play with it the signal gets better, however the antenna cable is not long enough for me to place the antenna by the window. I am assuming probably someone sells an "coaxial extender" out there so I have more room to move and play with the antenna, so should probably try to locate one of those.

Would an amplifier like CM-7777 make a difference if I am not seeing a difference between UFO with the amp on vs amp off. I take it these are much stronger amps than UFOs.

I am just so surprised how little (if any) difference the UFO made, but maybe I should try to locate a longer cable first.

Thanks very much for your help, hoping to dish comcast soon!
post #1631 of 3314
Thread Starter 
I wouldnt mess with adding a CM 7777 amp to the UFO. The internal amp is good enough.

Even a few inches can make a difference in finding a sweet spot.
post #1632 of 3314
yeah I guess I missed that part!

the 7777 wouldn't play well w/the ufo
post #1633 of 3314
RCA ANT751 Bottom View Photo I also took at CES2009:
http://photos.imageevent.com/holl_an...//P1040183.JPG
Click on image to see higher rez...
Here's an easy link to the side view I posted earlier:
http://photos.imageevent.com/holl_an...A%20ANT751.JPG

Look at the Driven Element (the one with thumbnuts for antenna connection).
I'm still puzzling out what the two short stubs might do...the ones that seem to go
part way forward and backwards, but not quite making contact to adjacent elements....
post #1634 of 3314
Thread Starter 
It looks to me like there are 4 active elements on that antenna.

The 2 rear and the UHF folded dipole and the element directly behind it.


Can you give me a rundown on what each element is doing on that antenna holl_ands?
post #1635 of 3314
I'll start from the big end and work my way "forward" through the RCA ANT751.
There aren't any Hi-VHF Reflector elements, although whatever it is mounted to
might act as a reflector (although perhaps not at the "optimum" distance).
Obviously the Hi-VHF Elements serve as Reflectors for the UHF section....
and the UHF Elements serve as additional Directors for the Hi-VHF section.

=================================
1. Active Hi-VHF Element, fed from Element#2 by Crossover Feedline.
These two elements form a basic Hi-VHF Log-Yagi "Cell".

2. Active Hi-VHF Element, fed from Element#4 via Non-Crossing Feedline.

3. Passive Hi-VHF Director, bonded to metal boom.

4. Passive Hi-VHF Director, bonded to metal boom.
[Let's hope there is no connection via the short stub from Element #5.]

5. Active UHF Folded Dipole Driven Element, 300-to-75-ohm Balun connects via thumbnuts.

6. If it is connected via stubs to Element #5, then it's an Active Element forming a Log-Yagi Cell
for UHF....but separation seems too close....
If not, maybe it's a UHF Passive Director that also helps to control SWR (so why bother to insulate it.....)

7. UHF Passive Director, bonded to metal boom.

8. UHF Passive Director, bonded to metal boom.

When someone gets one, let us know what the exact dimensions are so we can model it.

==================================
A Log-Yagi Antenna is a hybrid, taking a 2 (or 3) Element LPDA (Log Periodic Dipole Array)
and adding Yagi type Reflectors and Directors. More re LPDA:
http://glendash.com/Dash_of_EMC/Log_...g_Periodic.htm
Advantage of a LPDA design is ability to cover extremely wide bandwidths, although at
the expense of max gain....and a large number of elements.
Advantage of Yagi is good max gain, but limited bandwidth.
Hence Log-Yagi Hybrid attempts to meet somewhere in the middle....with cost minimized...

Further info is available (requires FREE registration): www.cebik.com

If you're interested, a LOGYAG calculator can be downloaded:
http://www.qrz.com/download/antennas/index.html

FYI: W-G YA-1713 LogYagi NEC Sim analysis:
http://imageevent.com/holl_ands/wgya1713
post #1636 of 3314
Quote:
Originally Posted by holl_ands View Post

When someone gets one, let us know what the exact dimensions are so we can model it.

I have an EZ HD, which appears identical to the new RCA. I believe I understand which measurements you need... I will measure it tonight and report back.
post #1637 of 3314
Quote:
Originally Posted by holl_ands View Post

Look at the Driven Element (the one with thumbnuts for antenna connection).
I'm still puzzling out what the two short stubs might do...the ones that seem to go
part way forward and backwards, but not quite making contact to adjacent elements....

If the links for holl_ands photos are broken, I have posted close-ups of the stubs in another thread:
http://www.avsforum.com/avs-vb/showp...postcount=9426

They appear to be UHF isolation stubs, that are usually 1/4 wave at the blocking frequency; both sections of the antenna will pick up UHF---one source must be eliminated before being combined.

Reference:
TV Antennas and Signal Distribution Systems by M. J. Salvati
section on Isolation Networks pp 86-87
Howard W. Sams 1979 #21584
ISBN 0-672-21584-5



Look for a used copy. Anyone who is interested in TV antennas should have one. It's worth the hunt.

More references:
http://www.avsforum.com/avs-vb/showp...postcount=7164
post #1638 of 3314
The "Made in USA" EZ-HD appears to be a dead ringer for the RCA ANT751:
http://www.dennysantennaservice.com/...v_Antenna.html
http://www.dennysantennaservice.com/...nna_image.html
http://www.dennysantennaservice.com/...nna_image.html

I can sorta make out the short stubs, but hard to say whether they are connected or not.
post #1639 of 3314
Yeah, dead ringer... right down to the yellow label with red and black printing on the boom.
post #1640 of 3314
My favorite basic loop and dipole (no amplifier) antenna is the RCA ANT111. I have successfully pulled in 2edge stations with it while having it laying horizontally on top of a window rather then standing up. I noticed that I always get better reception when I have the antenna i'm using (various types) in a horizontal position instead of having it stand up.

It's amazing what it can do and the price is great. I'd imagine it would work superb for a city viewer. (<10 miles and under).

It makes a great decoration for my room too. Even though I'm not using it right now.
post #1641 of 3314
Quote:
Originally Posted by EscapeVelocity View Post

RCA ANT751 on the way.





if this antenna is small enough i bet you could use it indoors if you nailed it into a wall or something. Are you gonna try it indoors out out?
post #1642 of 3314
Holl_ands, here are the measurements. (hopefully they are clear and understandable).

Dimensions of EZ HD, starting at front

Center of first element is located 1-1/8 inches from front end. First element is 6-1/8 inches long and 1 inch wide. It is riveted to top of boom, drops down 1/8 " along the side and then extends straight out.

Center of second element is located 5-5/8 inches from front end. Second element is 6-1/8 inches long and 1 inch wide. It is riveted to top of boom, drops down 1/8 " along the side and then extends straight out.

Center of third element is located 8-5/8 inches from front end
Third element is 11-1/4 inches long and 1 inch wide

Center of folded element is located 10-1/8 inches from front end
Folded element material is 1/2" wide
Length from balun connection to start of 45 degree angle is 4-1/8 inches
Each angled portion of folded element is 1" long and the joined portion extends another 1" The balun connect posts are 1-3/4" apart

Short stubs are 1/2 inches wide. They extend over the third element and first tubular element but do not touch the elements or the boom. The center of the short stub is riveted to the folded element, the feedline to second element from REAR and a plastic insulator. The short stubs have a flat piece that is 1-1/2 inches long (extends over 3rd element), a 45 degree piece that is 1" long, a flat piece 1 inch long (rivet is in center of this), another 45 degree angle 1" long, and a flat part that is 2" long (extends over first tubular element). The short stub starts 7-5/16" from front of antenna and ends at 13-3/4" from front of antenna. The feedline rivets (attached to folded element) are 1-3/4 inches apart OC.

The feedline between folded element and 2nd element from REAR is 9-3/4" (OC on rivets) and 10-3/8" in total length. It is 3/8" wide.

First tubular element from front is 25-1/2" long (includes both sides and boom). Each side element is 12-1/8 inches long. The first tubular element is 13 inches from front (oc on rivet).

The second tubular element from front is 26-1/2 inches long (includes both sides and boom). Each side element is 12-5/8 inches long. The second tubular element is 16-5/8" from front (oc on rivet).


The third tubular element from front is 29 inches long (includes both sides and boom). Each side element is 14 inches long. The third tubular element is 19-3/4" from front (oc on rivet).

The fourth tubular element from front is 34-1/4 inches long (includes both sides and boom). Each side element is 16-1/2 inches long. The fourth tubular element is 30-1/8 " from front (oc on rivet).

The cross overs between the third and fourth elements are made with 1/4" wide material. They are 2-3/4 inches apart (oc at 3rd and 4th elements). The cross overs are 1/2" away from boom (on side) and 1/4" away from boom (top & bottom). The total length of the each crossover is 14 inches. Do you need the length of each segment? If so, they are 2", 1" at 60 degree angle, 1" at 60 degree angle, 6 inches, 1" at 60 degree angle, 1" at 60 degree angle, and 2 inches.

The third and fourth tubular elements are above the boom (top side) while the first and second tubular elements are riveted to underside of boom.
post #1643 of 3314
Thread Starter 
Thanks very much for the detailed description holl_ands and the links to more info.


The Winegard 7000R seems a very similar setup and has some gain figures and front to back ratios at specific frequencies across the UHF and VHF spectrum, posted at Winegards site. The sizing and spacing seems the same or very similar but with elongated VHF elements to increase VHF Lo performance, I suppose. It even has the "stubs" you are talking about.

post #1644 of 3314
Thread Starter 
Here picks of the AntennaCraft G1483 Gray Hoverman. Dissappointed in the build quality. It has flimsy supports from the main tube, and the thin aluminum elements are super easy to bend and came that way in the box...I had to reshape the ends. The AD DB series put this one to shame, with its thick aluminum standoffs from the reflector screen and thick not easily bent aluminum whiskers.



post #1645 of 3314
Winegard 7000 may appear "similar" to HD-EZ and ANT751, but it's THREE times wider to cover down to Ch2.
post #1646 of 3314
IDRick re EZ-HD: I'm very close to making some runs...but a few more questions:

1. Diameter of tubular elements--don't assume they're all the same.
Try to be as accurate as you can, preferably using calipers.

2. What are boom dimensions - 1.00"x1.00"???

3. How far are the elements offset vertically above or below the boom??
Measure from boom to centerline of the element.

4. What is vertical offset of the top, middle & bottom parts of the Folded Dipole???

5. On the third element from the front, are the two halves electrically interconnected
(it may be hidden)??? Are they electrically connected to boom, elements or stubs???

6. For each element insulated from the boom, what is the closest metal-to-metal
Gap between the two halves of the element???

7. What is boom overhang distance measured from the center of the longest element???

8. Did the EZ-HD come with a standard 300:75-ohm Balun or some sort of Balun Box???
Either way, can you provide a photo...preferably inside the Balun Box if you have one...
[Macro photo hint--lots of light and use normal to wide vice telephoto lens setting.]

9. Can you provide a photo or sketch of the short stubs???
post #1647 of 3314
Quote:
Originally Posted by EscapeVelocity View Post

Did you try moving the antenna around to find a sweet spot, especially if you have obstructions warping the em radiation patterns? Over by the window. Stick it out the window and see if that helps.....never can tell what building materials you or your neighbor have that might be monkeying up the signals.

Wanted to thank you a bunch. I joined two coax cables and that way I was able to move the antenna around the room. I was so excited to finally find KUNS when placing the antenna at the very top of the window across the room from where the plasma is mounted. This window does face the direction of the signal. I can get the signal in the high sixties with my cheapie Artec antenna. However I dont see how I can perch my UFO on the tippy top of the window, too massive.

I guess now I need to find an antenna flexible enough to be able to mount next to my rear speaker. I was thinking of maybe the MANT940 cause I saw at target it looks like it could be mounted by the top of the window and small for indoors. Except i need VHF also. Getting closer now, though.

Again, many thanks.
post #1648 of 3314
is the attic out of the picture? if so, then try the roof
post #1649 of 3314
Quote:
Originally Posted by EscapeVelocity View Post

Oh, I remember you. Sorry.

Did you try moving the antenna around to find a sweet spot, especially if you have obstructions warping the em radiation patterns? Over by the window. Stick it out the window and see if that helps.....never can tell what building materials you or your neighbor have that might be monkeying up the signals.


And just to make sure, you did spin the UHF elements around in the disc right. position 1 is just to the left of 12 oclock and position 12 is at 12 oclock when facing the front of the unit looking down on it. So you can set it to 12 and then point the back of the unit towards the 140 degrees SouthEast.

How exactly does one "spin it"? Cause I'm making the assumption that the readout should face me as I view the thing so I can point the remote at it as needed. Even if #3 is at the back, as long as I keep it in the same position consistently, shouldn't it continue to receive consistently according to the way it's been set?
post #1650 of 3314
Thread Starter 
Short answer is yes.

I was just describing the orientation of the antenna within the disc as relates to the numbers on the LCD. 12 oclock is straight back, then 1 through 11 run counter clockwise, instead of like a regular clock. It doesnt matter how you have the antenna positined, you can spin it where you like it. I was just giving a way to know the orientation, so that he could move it around to find a sweet spot, in other words set it to 12 oclock and point the back of the antenna towards the compass heading of the transmission he is looking to bring in.
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