The Official AVS Antenna and Related Hardware Topic! - Page 342

They are the same Televes. Shouldn't the closer spacing eliminate the potential problems that I encountered?

Cool, I have not been around "the big boys" yet, I hope to make the right friends.. Although Riley from World's Toughest Fixes, does not mind talking with viewers...

Cool, was wondering if you were a ham.

Oh, wow, even at 6.5', I would have thought it would have been a pain at 70lbs for Rohn 45G (if the Rohn spec page is correct on weights)

Is this just as a hobby, or do you do tower work professionally?

Using very large U staples. Or a couple of holes in the mast to put lag bolts thru. As you can see, the sequioa is a pretty easy tree to climb.

Interesting Article in Communications Technology today:

http://www.cable360.net/ct/news/ctre...ted_34612.html

Enjoy,
Scott

Would you top the tree and put a mast with the antenna on it or just mount the antenna directly to the tree? Wouldn't the swaying of the tree in a storm cause problems? How would the tree's growth affect the mounting over time?

I have some large fir trees that I considered mounting an antenna on but haven't seen any info on how to do that.

John

Yeah you could top it, the firs and sequoia will still grow. The further down the tree, the less the sway. I imagine that the trees growth would bend the mast or pop out the lag screws over time, so it will have to be periodically remounted.

I have seen farmers plant firs about 2 feet apart, then topping them, to form a really nice cow fence / hedge in a few years time.

From channels 2-69 to 7-69 ? When did that happen instead of 2 - 51 ? My latest TVFool still shows that Ill have a channel 6 after June.
I really would like 7 - 69 instead of 2 - 51.

Channel 5 in Memphis will stay on 5 in June. When did the FCC change their mind?

The closer spacing will give you a wider main forward lobe and much smaller sidelobes. It will also give you less of a deep adjacent null. Wider spacing narrows the main forward lobe, increased the depth of the nulls, but also increases the sidelobes somewhat.

Narrower spacing can make it easier to "catch" Dx signals with the broader beamwidth.

Wider spacing provides the increased directivity needed to combat multipath and also eek out that last bit of gain on a distant signal. The disadvantage is that the extreme narrow beamwidth makes accurate aiming mandatory. A windy day that throws the stack off by only a few degrees could ruin the signal, thus a rotator is needed.

You might double-check the balun numbers on the DATs if you still have them. It's at least possible that the baluns could be mismatched.

Thanks for the advice. As soon as it gets warmer I'll go up the ladder, check the baluns and maybe increase the spacing.

Obviously, the CommTech writer (or his editor) was WRONG!!!

The FCC allowed stations to chose to operate on Ch2-6, if they want to.
What is REALLY happening is only 41 stations in U.S. actually chose Ch2-6:
http://www.rabbitears.info/ss/
That's 7 on Ch2, 7 on Ch3, 2 on Ch4, 16 on Ch5 and only 9 on Ch6. So there
is a market for Ch7-13 and Ch7-51 antennas.....in ADDITION to Ch2+ monsters....

In California, the ONLY Ch2-6 DTV is Ch3 in Eureka (near Oregon border).

This could increase when low power DTV station assignments sort out....
Hmm, much lower monthly electricity bill and lots of excess equipment
to chose from at the surplus sales....

And maybe "White Space Devices" will be forced to reconsider Lo-VHF, esp.
for those metro areas that don't HAVE any extra UHF channels....

And it's possible Ch6 is opened to expand FM band....except for perhaps 9 DMAs...

Just a hobby.

Also a good idea. I just want my channel 6 to go to a higher channel number and I dont really care how they do it, heh. Its such an oddball pain for me.

My gut feeling is that these vhf-low stations are holding out for a better deal from the FCC, heh.


You would think that someone in the field like that would get it right. Its not that hard, heh. Wheres he getting his technical info from, the YouTube antenna guy ?? Heh, heh.

Only 120 ft ? In that case I may be up there in only 4 years, heh.

Does anyone know anything about the Alliance Tenna-Rotor? Are they any good?

I've come across one and I noticed that it has four terminals.

do you know what this antenna is

Looks like a Radio Shack VU-90(Channels 2-69 )

Yep, that would be my guess too.



I still have mine I bought around 1973, and its still working. Ive gotta get around to replacing the five wire cable though, cause its bare in some places, heh. Ive rebuilt and regreased it a few times. Mostly what goes bad from age in it is the non-polarized electrolytic capactor. Its a very simple circuit.
Since you have the four wire one, that means you probably dont have a needle that tells you the direction.

What kind of controller does it use? All I have is the rotor.

With the 4 wire model, I believe it used the "clicker" type rotator. My parents had that one in the 50's. You would dial it for the direction you wanted (after the rotor was initially aligned with the right compass point) and it would click step by step until it reached that point. The click was fairly loud, heh.

With my compass needle model, you have to hold the button down (either to the left side or the right depending on the direction you want to go) until it gets to the desired direction. Its quiet.

There are different models of the 4-wire tenna-rotor T10, T12, U98, U100 and U110. Are there any numbers on the rotor, or what color is the weather boot on the top. I may have a controller here.

Good point about the model number. I went out and checked mine. I have a model T-45.


On the inside of the rotor itself, its just straight wiring to the motor and ground, IIRC. So its likely any of those 4 wire control boxes would work. (Worse case scenario, in reverse)

And the way you wire it up is, one wire in the flat wire group is silver and the others are copper. The silver went on 1 and the rest of the numbers followed what was stamped on the rotor and the control box.

There isn't a weather boot on the rotor. I did see the numbers "02 79" stamped on the bottom of the case. Unfortunately, I don't see any other numbers (except the patent number on the name plate).

Under the cover plate (in really bad shape) for the terminals, there are numbers stamped on the edge.

Upper Left: 1
Upper Right: 2
Lower left: 3
Lower Right: 4

The rotor has six screws holding the case together.

For my location (45056), a reflectorless DB2 is netting me the most digital channels: 24.

I tried a DB1, DB2 and DB4, each with and without reflector panel, each with and without the pre-amp I picked up from solid signal. The one constant was my 28db amplified distributor and my Vizio TV.

So, until I install the J-pole from my previous satellite dish on the roof and go external, the DB2 without reflector and no pre-amp gets me 24 digital channels.

I am in an odd location with Dayton stations being at 51 degrees (average) and Cinci being at 166 degrees (average). In any config, I don't want to use a rotator. Two TVs will eventually be attached to this antenna.

I found it odd that the DB4 lost 22.1 and 45.1/45.2 compared to the DB2 in identical set-up. It must be reflections aiding my reception.

Thus, I am done for the now with the attic experiments. Time to clean up all my antenna gear! The wife has been giving me strange looks regarding my pile-o-antenna.

I may have an Alliance manual somewhere. I will see if I can find it.

Those will definately need to be cleaned up or replaced.

Heh, Norms a little pricey, isnt he. Interesting, the instructions say silver wire on terminal 3, (ground ?) instead of on terminal 1, like I use.

Yeah, my parents had the U-100/110 "clunk clunk" control box plus a double bay vhf bowtie antenna, (single bay shown in the instructions). And its always been HDTV ready, heh.

I think I only paid $23 to $29 for my Alliance unit new back in the 70's. The two downlead from two separate antennas into an A-B switch is a much faster solution for me. The "clunk clunk" control box probably slows the rotor down to 1/3 rpm from its max speed of 1 rpm.

Yeah, the things should last forever with a periodic servicing and replacement of that elec cap. Its pretty easy to service. IIRC, the motor in the rotor is the same as used in old phonograph turntables. My gears werent hardly worn at all.

The fork spade ends are still on the rotor I have and it looks like the silver fork spade is on terminal #3. I did notice that the rotor is stamped with 1 rpm.

I have had this problem happen to me twice now, and I am not exactly sure what caused the problem, so I will try to explain in detail what we did, and what the results were, and how the problem was addressed. But my main question is, why it happened in the first place, because I would like to be able to recognize the situation, and to be able to avoid it in the first place...

First scenario: I have a friend who lives out west of Beaumont, Texas. He bought a RS VU-190 antenna and a RS pre-amp. We installed the antenna up about 36 feet, and when we hooked it up to the converter box or straight to the TV, we got absolutely no channels whatsoever. The tuner was blanked out, like it was overloaded. When the antenna was pointed at 90 degrees to where the local stations were, we were able to get the full power stations on the converter box, but the antenna had to be pointed backwards to get the analogs on the TV.
On the advice of someone I know, I bought a 3dB pad to install before going into the A/B switch so that my friend could toggle back and forth between analog and the converter box. This helped, but he was not able to recieve the digital LP station and still can't.
I originally blamed this on the RS pre-amp and internal noise causing the overload. He lives about 15-20 miles from any full power TV transmitters.

Second scenario: I have a co-worker who lives in the Lake Charles, Louisiana area. Thinking that the RS pre-amp was the cause of the overloading in the original antenna project, I advised him to get a CM 7777 pre-amp. Installation went perfectly. No tuner overload. multiple stations from 3 DMAs from about 30 feet up. He wants to do the same for his dad who lives about a mile from him.

Third scenario: My co-workers dad buys the same set-up. RS VU-190 antenna and CM 7777 pre-amp. 30 feet up.
Hook it up to the converter box... nothing. Nada. Zilch. Take the amp out, locals come in fine, but no distant stations.
His dad decides that the original location for the pole does not suit him, so my co-worker decides to move the antenna to the other side of the house. In the new location, he decides to install the CM 7777 pre-amp back on the antenna, and voila, no overload. Beautiful signals from multiple stations in 3 DMAs.

So... What the heck gives??? Why the overload. No nearby TV or DT transmitters. FM trap in. How do I avoid all the trouble and work of installing an anteanna only to have the tuner blank out? I'm a little gun shy now. Two other installations that I have consulted on went well, one at 16 feet and one at 25 feet.
We are fixing to do one at 20 feet for a friend who lives a couple of miles from my friend in scenario one.
Can onyone give me some insight on what may have caused the tuner overload? I would like any information that might be pertinent. I would like to know what to look for.Thanks.

What do the TV Fool plots look like in each location?

I would avoid high-gain pre-amps, such as the CM7777 in any area that has signals in the green on TV Fool, unless you don't need to point the antenna in the direction of those stations.

TV transmitters at 15-20 miles are rather close, especially if you have LOS.

Do you need Low-VHF? Most areas do not need Low-VHF for DTV and that might save you some headaches. A 7-51 antenna is less cumbersome as well.