OTA Antenna Setup Questions

[larryl]

I'm trying to design a good solution to receive HD stations OTA. Local analog are provided by DirecTV, so I don't care about those.

Good news: I live in a far corner of town, so while the towers are about 40 miles away they are all conveniently within 4 degrees of each other. This part of Texas is flat.

Medium news: All the stations are UHF except for one, ABC. I want that VHF signal.

Bad news: My homeowners association does not allow ugly dogs on the sidewalks, thong bathing suits at the pool (a travesty in my opinion), or antennas of any kind on the rooftops. I had to mount my satellite dish below fence level in the back yard.

Preliminary research here and at antennaweb indicates that I need a medium directional antenna. I've already scoped out the DB4 and Channel Mater 4228. So the questions:

1. Do I need a beefier antenna since I'll be mounting in the attic?
2. Will these things even work in the attic?
3. I have a low attic with loads of space and a high attic that is very tight and difficult to get around in. I assume higher is better? {sigh -- I already know that answer}
4. My builder thoughtfully installed a UHF/VHF/FM antenna in the high attic. I have no idea what model it is, but it is a 12-foot behemoth. It is not movable but appears to be pointed around 200-ish. I get zero signal from it on any frequency as measured by the DirecTV HD DVR receiver, even with a Radio Shack pre-amp. Does that seem right? I expected to get *something*.
5. What do I need to get that one lonely but important VHF station? A second antenna or some kind of combo setup?
6. The Radio Shack guy said I needed quad-shielded RG-6 instead of my regular shielded RG-6. This sounds like whooey to me. Do you agree? The run is less than 100 feet.

Here's my info (for 75013):

lt green - vhf 200° 38.7 9
lt green - uhf 196° 40.9 48
lt green - uhf 199° 38.3 24
red - uhf 196° 40.9 32
red - uhf 200° 38.7 35
red - uhf 199° 38.3 51
red - uhf 197° 38.6 14
red - uhf 196° 40.9 43
red - uhf 196° 40.9 18
red - uhf 199° 38.5 40
red - uhf 197° 38.5 19
red - uhf 199° 38.5 41

Thanks for any help you can offer.
Larry

[kevinw]

I like it when you research ahead of time.

I would not worry about the RG6, that is fine.
Your exsiting antenna should work, even though you are a long way for an attic mount.
I would check to make sure that you have the correct cable connected to the STB. If possible check to see if it is a direct feed to your STB also. To many splits can drain the signal. This may mean hauling the STB up in the attic with a portable TV to check for signal.
No need to worry about the lone VHF. It is a higher band and most good UHF- like the 4228 will pick up the signal.

If you get the 4228, it can be mounted outside with out much problem. Small enough to not be seen to well and BTW HOA's can not really keep you from having one.

[mjones73]

Your HOA can not in any way by FCC law prevent you from putting an antenna up on your property, If your up for a fight which your HOA can't win I can give you a link the law...

1. Yes, you lose about half your signal with an antenna mounted antenna. If the insulation around the attic (the foam panelling they put under siding) is metal coated or your roof is metal or you have a stucco coated house (they put metal grids inside it to hold it to the house) you might not get any signal at all.

2. Yes, see 1

3. Higher would be better of course but it wouldn't hurt to try the lower attic first. Run some temp cable and move it around to find the best location before you go hiding the cables in the walls, etc..

4. You should probably get something unless your attic is blocking the signals from getting in. You might want to run a temp cable down from it to rule out the existing wiring isn't damaged.

5. You *might* be able to get 9 with a UHF antenna since it's in the higher VHF band, if not, a combo antenna like the one you already have would work. The CM 4228 that Kevin mentioned would be a good place to start, a CM 7777 pre-amp wouldn't hurt either to go with it.

6. Regular RG-6 should work fine.

[larryl]

Thanks for all the suggestions.

I ran a temporary coax directly from the antenna in the attic to the STB. I managed to move the antenna a little bit and suddenly picked up a truckload of the UHF channels. Pretty good signal, from 75 to high 90's. I moved back to the in-wall cable and they were still there. So far so good.

The VHF station is still giving me problems. It did not come in at all during the day, then came in badly last night. Signal strength was in the mid-40's. I suspect one of the long elements of the antenna is touching one of the rafters way back in the far corner of the attic. Would this affect reception? I can't decide if a non-conductive surface touching the antenna would make a difference.

Antennaweb suggests that this should be one of the easiest of the stations to pick up at my location. I'm going to try shifting the antenna to get it off the rafter and tweaking the direction again today to see if I can bring it in better.

[hd4me2]

The problem is that the ABC digital signal is only tramsmitted at 18.6 kW and most other Dallas digital stations are at 1000 kW. The only thing you can try is to aim the antenna as best you can and get a very good pre-amp, dump the radio shack model. I would suggest the Channel Master 7777 pre-amp, it's both UHF and VHF. It sounds as if you might have a chance since you are getting some signal at certain times of the day. Go to www.channelmaster.com and you can find a local dealer to buy the pre-amp. Let us know how things turn out and good luck!

[mjones73]

Just curious, did you try the RS pre-amp after you aimed the antenna? I'd give it a shot before you take it back... If it doesn't work, the CM 7777 would be the next logical step as noted by hd4me2.

[mjones73]

hd4me2, where did you find the transmit power ratings at? I'd like to see what all the local stations around me are. Thanks

[Ratman]

www.fcc.gov

[hd4me2]

Here is a more direct link to the Table of Station Assignment and Service Information: http://www.dtvinfo.com/fccinfo/DA-04-3203A2.pdf. FYI, the Maryland info is on page 28 and DC is on page 12.

[mjones73]

Thanks guys

[larryl]

Here's where I ended up.

The weak ABC station disappeared from view completely after a while. I tried moving the existing antenna to dial in the angle better, but it didn't work.

I ordered the 7777 pre-amp and a 4228 antenna from Solid Signal. The pre-amp went on the antenna first and immediately netted me better signals across the board, including bringing in the ABC station with strengths averaging in the mid-60's. The strong channels were all reporting at least 70's and most were in the 90's. The Channel Master pre-amp is obviously a much better piece of equipment than the Radio Shack model I purchased.

I threw the 4228 up in the attic today. I literally laid it in a corner, leaned it against a rafter, aimed it more or less at 200 degrees and more or less upright, and hooked up the 7777 pre-amp and cable to it. All of the strong channels are still strong, although a few than had been averaging 95 were now averaging 90. The CBS digital signal went from high 70's to low 90's, and the weak ABC digital signal is now reporting 90 as well.

The pre-amp made the biggest difference, but switching to the 4228 let me fine-tune a couple of the stations that had been weak and intermittent. I've got strong signals across the board and a fully functional system now.

Thanks for all your help and informative steers.

Regards,
Larry

[tigerbangs]

Larry, if you made that much of an improvement putting the antenna in the attic, imagine how much better it would be if you ACTUALLY MOUNTED IT OUTSIDE, WHERE GOD AND CHANNEL MASTER INTENDED IT TO BE....LOL