no UHF HD reception?!?

bp787

SatelliteGuys Family
Sep 7, 2004
35
0
I recently installed my OTA antenna. The installation isn't complete yet, as I need to get a taller ladder to get the antenna up higher, so I'm sure that will be "some" of my problems.

I currently have the antenna signal combined with the satellite signal using a D920 RCA diplexer and then being separated at the receiver. I'm using a DTC-100 (old school, I know :p). The antenna is a VU-120 XR.

I'm in Bloomington, IN and am trying to get the Indianapolis HD channels. I am currently able to receive Ch 8, CBS, which is the ONLY VHF HD channel coming out of Indianapolis. Without tweaking the pointing and height, I'm getting about a 50 signal strength. Picture looks good, etc...

However, I can't get ABC, NBC, or Fox at all. I can get ABC and NBC in on analog, however, but they're very snowy. The analog versions of those channels are all on VHF, except fox which is on UHF on analog also.

Also, I DO get the local PBS, and pax/worship/etc (WTIU)... channels. Strangely enough, WTIU and pax are on UHF. They don't come in very well, and often pixelate. Those two digital stations are also in a different direction. about 30 degrees east of the indianapolis stations that I want. So I could probably improve those stations reception by reaiming, but I don't care about getting them ;)

Anyway, so it seems that I have a problem with UHF. I'm wondering if the diplexers could be a problem? I'm going to try running a straight through connection tonight, but if that's not it, I don't have a clue to what to look at next, besides getting the antenna up higher.

If you have anything that I might have overlooked, that would be great!
 

Carl B

Supporting Founder
Supporting Founder
Dec 13, 2003
920
0
Arvada, CO
Have you looked here to see which digital channels (real channel numbers, not the X-1 virtual channel numbers) you should be able to get, plus their direction, distance, and the type of antenna needed to receive them?
http://www.antennaweb.org/aw/welcome.aspx

That should tell you whether they are VHF or UHF DTV channels. Then look here to determine the ERP of your digital channels of interest. Many DTV channels are extremely low power and can't be received more than a few miles from their towers. I'm not in your area, so I don't know the local situation.
http://home.earthlink.net/~w9wi/tvdb/index.htm
 

bp787

SatelliteGuys Family
Sep 7, 2004
35
0
yeah. I've checked those. The only channel I'm receiving from indianapolis (approx 50 miles away) is CBS which is VHF. I don't get the other 3-4 networks that are on UHF. And I have trouble receiving UHF local stations within 20 miles.
 

Kevinw

Just a regular guy
Pub Member / Supporter
Dec 2, 2003
2,992
13
Jacksonville, FL
THe V120 is a VHF/UHF antenna. Most likely your alignment is off. 20 miles is plenty close enough but you need to be more specific when pointing. You may want to consider a rotor. While the V120 is usable it is not the best antenna it is adequate
Add to the fact that diplexing can drop your signal 2-3db's if not more.
 

Carl B

Supporting Founder
Supporting Founder
Dec 13, 2003
920
0
Arvada, CO
What color antenna does antennaweb.org say you need for the UHF channels you can't receive? What is the ERP of the UHF Digital channels you can't receive (see my second link above)? 50 miles is pretty far for a Digital UHF signal unless it is full power and unless you have a good pre-amp on your antenna.
 

bp787

SatelliteGuys Family
Sep 7, 2004
35
0
Carl B said:
What color antenna does antennaweb.org say you need for the UHF channels you can't receive? What is the ERP of the UHF Digital channels you can't receive (see my second link above)? 50 miles is pretty far for a Digital UHF signal unless it is full power and unless you have a good pre-amp on your antenna.

Of the following, I'm receiver number 2 in HDTV with a steady 55 signal strength. I receiver numbers 1 and 10 in analog, although number 10 is quite snowy.

Thus, I get CBS in HD. It's a VHF station. I have a weak signal or no signal on the rest with absolutiely no picture on the digital stations.

1. Indianapolis, IN WISH-TV [ 8] 316.0 305.0 - E 39°53'25"N 86°12'20"W TV-LIC CBS
2. Indianapolis, IN WISH-DT [ 9] 19.50 284.0 H 39°53'25"N 86°12'20"W DT-LIC CBS
3. Indianapolis, IN WRTV-DT [25] 898.0 294.0 39°53'58"N 86°12' 4. 2"W DT-LIC ABC
4. Indianapolis, IN WRTV [ 6] 100.0 279.0 Z H 39°53'58"N 86°12' 2"W TV-LIC ABC
5. Indianapolis, IN WXIN-DT [45] 700.0 285.0 H 39°53'20"N 86°12' 7"W DT-LIC Fox
6. Indianapolis, IN WXIN [59] 4470. 304.0 - C 39°53'20"N 86°12' 7"W TV-LIC Fox
7. Indianapolis, IN WTHR-DT [46] 1000. 264.8 H 39°55'43"N 86°10'55"W DT-LIC NBC
8. Indianapolis, IN WTHR [46] 700.0 267.0 39°55'43"N 86°10'55"W DS-STA NBC
9. Indianapolis, IN WTHR [46] 1000. 267.0 39°55'43"N 86°10'55"W DS-STA NBC
10. Indianapolis, IN WTHR [13] 316.0 299.0 - C 39°55'43"N 86°10'55"W TV-LIC NBC


I do NOT have the preamp/amp up yet. I am approximately 57 miles from the towers according to Antennaweb. It's violet. I realize I'm pushing the limits on the UHF. However, I have a friend about 2 miles from me who is getting everything except for the fox digital. His ABC comes in but drops out more than he'd like. He has an OLD antenna with bent vanes, etc...
 

bp787

SatelliteGuys Family
Sep 7, 2004
35
0
Kevinw said:
THe V120 is a VHF/UHF antenna. Most likely your alignment is off. 20 miles is plenty close enough but you need to be more specific when pointing. You may want to consider a rotor. While the V120 is usable it is not the best antenna it is adequate
Add to the fact that diplexing can drop your signal 2-3db's if not more.


i should have probably gone to the next up antenna that they had. but I just helped a friend install the bigger one, and he didn't really do much better.

The 20 miles is for the local PBS, etc... I don't really care about that channel. My main goal is to get the channels that are about 55 miles north of me. THey're all in a antenna farm or at least very close to each other. So I shouldn't need to rotate the antenna for any of the 4 I want. But yeah, I know what you mean.

I'll definitely remover the diplexer and then reaim the antenna. Then I'll add in the preamp and see what happens. And, I'll be raising the antenna about 5-10 more feet as soon as I get a big enough ladder to get that far up.
 

Carl B

Supporting Founder
Supporting Founder
Dec 13, 2003
920
0
Arvada, CO
ERP of the channels you want seems to be reasonable. At 55 miles you do need the right hardware and a pre-amp (CM Titen 2 series are among the best). You also need as much elevation as is practical to achieve. I'm thinking at least 25 to 30 feet above ground level.

Antennas are a mixed bag. The CM 4228 or a CM large Crossfire may be the ticket. Also consider a Winegard PR-8800 or PR-9032 or PR7052. The downside of the CM 4228 is that it is big and heavy. In general, the Winegard antennas are going to last longer in the weather than the CMs, if that is a consideration. There are no guarantees with antenna selection as far as reception goes. I'm guessing that your neighbor who receives more UHF channels than you has more "metal" on his antenna mast (i.e., more metal in the make-up of his antenna) and/or it is at a higher elevation.

This link provides some computer analysis values for antenna gain for some common antenna models and types:
http://www.hdtvprimer.com/ANTENNAS/comparing.html
 

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