DigiTenna Metro soffit mounting?

[ArgMeMatey]

Anybody got a review of the DigiTenna Metro (aka DUV-Metro, DUV-M)?  

I am 0.6 mi SE of the WITI-6 tower.  Looks small enough to try on the soffit (18.5 x 33").  Closest trees are probably 35 feet away.  The spec sheet says 4.9 dB on Ch. 10 and 5.5 dB on Ch. 51.   Plan B is to put it on the roof, where I have clear line of sight to all towers.  

I thought maybe the indoor rabbit ear/UHF loop combos would be good enough but the WAF is below threshold.  

What about lightning?  I am thinking I would use an RG-6 with ground and connect the ground wire to my electric ground which is right next to the TV amp in the basement.  

Any comments or suggestions welcome.  Thanks.

[WPXE ION]

Try the attic if available. Usually not recommended to put in the attic, but you are so close that the signals should penetrate the roof well. Unless its a metal roof.

Otherwise if you want to mount under the soffit, look for a used satellite dish mounting bracket. It can be modified with a few parts from the hardware store to be mounted upside down under the soffit.

[Nels Harvey]

Anybody got a review of the DigiTenna Metro (aka DUV-Metro, DUV-M)?  

I am 0.6 mi SE of the WITI-6 tower.  Looks small enough to try on the soffit (18.5 x 33").  

You are pretty close to the TV towers.  This puts you under the "cone of silence" as it is called.  In those areas, there is a lot of multipath signals that can conflict with your main reception.  The suggestion above of placing the antenna in the attic could possibly give you a better main signal ratio to multipath signal than placing the antenna outside.

I am over 6 miles north of the towers, and an attic antenna works fine for all the stations here.

[ArgMeMatey]

You are pretty close to the TV towers.  This puts you under the "cone of silence" as it is called.  In those areas, there is a lot of multipath signals that can conflict with your main reception.  The suggestion above of placing the antenna in the attic could possibly give you a better main signal ratio to multipath signal than placing the antenna outside.

I am over 6 miles north of the towers, and an attic antenna works fine for all the stations here.

Thanks.  I'd love to try the attic.  Tell me what you think of this:

The only space I have is a knee wall crawl space.  The antenna is 18.5" long so, assuming the best way to mount it would be parallel to the floor, I should be able to mount it about 30" above the floor.  Or would it be better to try another antenna in the attic?

In the spot where I would put it, I have an 8x12 sheet metal duct about four inches above floor level, so the duct would be (30-12=) 18 inches below and "in front" of the antenna. Would this be a factor?  

Also I've got a pretty thick roof, sloped 9/12:  
5/8 sheet rock with vapor barrier paint
6" icynene foam between 2x6 rafters 24" on center
1x6 roof board
Tar paper
Wood shingle layer
Asphalt shingle layer #1
Asphalt shingle layer #2

We'll be re-roofing within a few years, but that's not imminent.

[Nels Harvey]

Thanks.  I'd love to try the attic.  Tell me what you think of this:

The only space I have is a knee wall crawl space.  The antenna is 18.5" long so, assuming the best way to mount it would be parallel to the floor, I should be able to mount it about 30" above the floor.  Or would it be better to try another antenna in the attic?

The attic may, or may not work well.  It certainly is easy to try it, however.  Just hang the antenna from the rafters with a string, run a cable to the TV, then try it out!  If the reception is good, secure the antenna and cable and enjoy it!  Different locations in the attic may work better than others, so try different locations.

There is a whole lot of theory on antennas.  Terms like resonance, impedance, forward gain and reverse rejection, are just a few things.  Leave that to the engineers.  Hook up the antenna, and if it works, you're done!  I do wish you well!

[ArgMeMatey]

Will a larger antenna help appreciably with multipath?  

I consulted with a local retailer and tried a DigiTenna DUV-IN in the attic space I mentioned earlier.  

Signal levels were better than I expected.   I checked signals on a Digital Stream 99xx converter, model 15-149.  The best reading on that converter's scale was 93, on 10.1.  But with those levels on 10.1, I could achieve only 78-88 on 6.1, 72-85 on 55.1 etc.  

I re-oriented slightly, moving the antenna away from the knee wall, toward the roof.  10.1 dropped to 91.  4.1 dropped considerably to 75-76, 6.1 hardly changed, and the rest were at 86-91.  Except 41.1, 30.1 and 63.1, which I am not concerned about.  

But I still have multipath issues when a car goes by or even when somebody was walking downstairs under the DUV-IN.  The DUV-IN specs do not list a front-to-back ratio, so I wonder if it would help to step up to the DUV-M, which lists a F to B ranging from 8.6 to 16.4.  

Setting the DUV-IN on the roof didn't make a whole lot of difference overall.  I got noticeable increases on 4.1 and 6.1, but nothing else changed much.

[Nels Harvey]

Will a larger antenna help appreciably with multipath?  

I consulted with a local retailer and tried a DigiTenna DUV-IN in the attic space I mentioned earlier.  

The antenna that you have doesn't have any real directionality to it that I can see.  Using that antenna, I would try to attenuate the signal that it picks up.  The signal levels that you mention are 'Figures of Merit', not signal strength as one would find on an s-meter.

I would suggest trying an attenuator, and see if that helps.  Attenuators are available from places like Radio Shack.  They usually are found in 10db increments.

If you have a two for one splitter, try putting the signal from the antenna  into one port, and out one of the others.  If you go in the single side, and come out one of the two other ports, there is about a 3db loss.  If you go in one of the output ports and out the other, there is about a 12db loss.  What I'm thinking is this may attenuate the weaker reflected signals, and actually give you a higher 'Figure of Merit'!

Another thing to be aware of is signals may be entering poor quality cable.  Braided cable is usually poor.  The cable you should use is the kind with a complete aluminum shield.  It is usually cheap, but works better than the braided kind.

A higher gain antenna creates a more directional factor where you will see differences as you point to each of the TV antennas.  Unless you are in line with Ch. 4's tower, Ch. 12's tower, Ch. 6's tower, Ch. 10/36's tower and Ch. 18's tower,  a higher gain antenna will probably need to turn, or find a compromise position.

I think it is harder to receive a clean signal where you are located than for someone further away.  I do wish you well!

[ArgMeMatey]

I think it is harder to receive a clean signal where you are located than for someone further away.  I do wish you well!

Thanks for the comment Nels.  I have an infinitely adjustable attenuator, although I have no way to check the slope.

Also the wind tomorrow should be a good acid test as that's always caused issues for the rabbit ears and loops.  

Doing a little googling on multipath, this looks like the cat's meow.  Make sure you check page 2 as well:
http://www.prism.gatech.edu/~wn17/

[ArgMeMatey]

I ended up with the DUV-S.  The foil in the photo is leftover from my experiments with the Metro.  Note the highly sophisticated dual-pivot mounting apparatus.  

Haven't noticed any dropouts or pixelation.  I'll be interested to see what happens when the leaves come back in full, and when the roof is loaded with snow.