OTA Multipath

[rcwilcox]

I have a CM 4221 in the attic. Quite a pain to get it there but it is there. I get all the channels I should and i get plenty of signal but multipath seems to be a problem especially on the strongest stations. My question is putting an antenna outside in lieu of the attic, would that help with multipath? I have the worst possible situation for direction to the towers some real close due north some east and one south. I know the 4221 is directional but----- I need a fair amount of signal for a couple of the stations. Any suggestions?

 

[boba]

I have a CM 4221 in the attic. Quite a pain to get it there but it is there. I get all the channels I should and i get plenty of signal but multipath seems to be a problem especially on the strongest stations. My question is putting an antenna outside in lieu of the attic, would that help with multipath? I have the worst possible situation for direction to the towers some real close due north some east and one south. I know the 4221 is directional but----- I need a fair amount of signal for a couple of the stations. Any suggestions?

What is your zip code? What type of building construction,1story/ brick/aluminum siding/metal duct work in attic to reflect strong signals? Seeing we can't see your location as much information as possible will help answer your question. What multipath symptoms are you getting seeing you have strong signals?

 

[rcwilcox]

What is your zip code? What type of building construction,1story/ brick/aluminum siding/metal duct work in attic to reflect strong signals? Seeing we can't see your location as much information as possible will help answer your question. What multipath symptoms are you getting seeing you have strong signals?

One Story plus bonus room. Hardiboard siding mostly below antenna level. zip 32608 Symptoms= 100% signal or close to it then message "signal lost" then back after a few seconds. Worse when the wind blows or rain. Using a dish 622 BTW. When the antenna is hooked direct to TV it is much worse. Duct work is fiberglass that is foil covered. house 10 years old.

here is antenna web data
WCJB-DT 20.1 ABC GAINESVILLE, FL 152° 5.7 16
* yellow
uhf WGFL-DT 28.1 CBS HIGH SPRINGS, FL 288° 7.5 28
yellow
uhf WBXG-CA 31 BOX GAINESVILLE, FL 42° 3.3 31
yellow
uhf WCJB 20 ABC GAINESVILLE, FL 152° 5.7 20
* yellow
uhf WUFT-DT 36.1 PBS GAINESVILLE, FL 31° 8.0 36
yellow
vhf WUFT 5 PBS GAINESVILLE, FL 31° 8.0 5
* yellow
uhf WOGX-DT 51.1 FOX OCALA, FL 161° 18.6 31
yellow
uhf WOGX 51 FOX OCALA, FL 161° 18.6 51

Not listed is new channel 9 NBC same location as WGFL comes in at 70% or so very stable

 

[boba]

You have got some problems for your main broadcasters you are 4-17 miles from there towers and worst they are from 9degrees to 171 degrees from you. TV Fool - Home gives better information than antenna web. After 2/17/09? you will have 2 VHF broadcasters so your Channel Master may not work 1 will be a low power on CH5 VHF. As close as you are to the towers have you tried a simple set of rabbit ears maybe set on the top of the TV.

 

[rcwilcox]

You have got some problems for your main broadcasters you are 4-17 miles from there towers and worst they are from 9degrees to 171 degrees from you. TV Fool - Home gives better information than antenna web. After 2/17/09? you will have 2 VHF broadcasters so your Channel Master may not work 1 will be a low power on CH5 VHF. As close as you are to the towers have you tried a simple set of rabbit ears maybe set on the top of the TV.

yea rabbit ears don't get 51(31) or 28 as i said in my first post i know it is a bad situation several directions some close some far away

 

[Don_M]

The antenna may need to go outside regardless. Those foil-lined ducts aren't helping matters. Also, how is the roof built? Asphalt shingles on a plywood deck are OK; tiles and/or a radiant barrier, both common materials in newer Florida construction, block signals. Sure sounds like you're relying on signal reflections around something!

You'll still have reception-robbing multipath on some of the channels if the 4221 is aimed at a fixed location outdoors. That antenna needs a rotor. The surest way around this issue is to buy and install the following items:

* Rotor such as the Channel Master 9521a
* VHF-high band antenna like the AntennaCraft Y5-7-13, plus balun
* UVSJ band combiner
* Mounting bracket, two masts, extra lengths of coax, grounding line/rod, etc.

Mount the VHF-high antenna below the rotor and aim it permanently at WNBW 9.1; mount the 4221 above the rotor; connect antenna outputs to UVSJ inputs; attach downlead to UVSJ output.

 

[rcwilcox]

OK. It sounds like the attic location could be a problem. Roof is asphalt and plywood no radiant barrier but it is close to some of the duct work and with it being on the same level as the bonus room I think that might compound the problem with duct work/wiring and furnishings in the bonus room right at the same level as the antenna. I will at least try the CM outside on a mast and see if that helps. Good input thank you.

 

[Jim5506]

Bow tie antennas are not recommended in the attic.

There are all sorts of multipath sources there.

Put 'er outside.