Optimal antenna configuration

fool · 5-Apr-2012, 5:12 PM

I live in metro Boston area and decided to experiment with OTA channels and then cut the cable. I bought a cheap HD antenna from monoprice (http://www.monoprice.com/products/pr...seq=1&format=2) and putting it indoors on top of TV cabinet, pointing south east, I can pull 20+ channels mainly UHF from Boston.

My TVFR http://www.tvfool.com/?option=com_wr...267e8690be38a3

After reading a lot on this form, and being a tech person, I was amazed by the depth of issues surrounding OTA antennas. I am more comfortable now with various issues like UHF/VHF, gains, directions, not able to combine antennas (except maybe UHF+VHF if done correctly) etc.

My setup is single TV in living room so I don't think a splitter/amp is needed.
It is a classic one level ranch style construction, wood siding and asphalt shingles. Attic is kind of flat (can't stand upright) with insulation on floor and nothing on ceiling. There are tall pine treed in the backyard (facing east/south east) and in general the area is wooded.

There is also an old antenna on the roof put up by previous owner (pre-2009) so I guess it was used for analog signals. I have to check it's wiring and experiment a bit.

Can I improve my setup, still keeping it simple, or just stick with current cheapo antenna?

ADTech · 5-Apr-2012, 6:40 PM

Boston is considered an all-UHF city. Unless you want to experiment with adjacent markets, there really isn't much else to be done if those channels are received reliably. For example, WMUR, ABC in Manchester, is available if using a high-VHF channel. WMUR's network programming will usually mirror that of Boston's WCVB. There are two VHF stations out of Providence that are likely receivable, the CBS and Fox affiliates. Again, the network programming will be generally the same as the Boston affiliates.

You'll have to look at your TVFool plot to see if there are nay of those or other stations that are on you list of stations you'd also like to have. If so, we can look at what might be needed.

MisterMe · 5-Apr-2012, 8:00 PM

Quote:

Originally Posted by fool

...

There is also an old antenna on the roof put up by previous owner (pre-2009) so I guess it was used for analog signals. I have to check it's wiring and experiment a bit.

Can I improve my setup, still keeping it simple, or just stick with current cheapo antenna?

If that "old" antenna is still on the roof, then the first thing that you should do is to see how well it works. That is, how many channels do you receive with it. You see, the only thing that an antenna does is to receive RF signals. The set of RF signals that broadcast today's digital signals in Boston is a subset of those that broadcast the analog signals in the Boston area in days of yore.

With the "old" antenna connected to your TV, scan for AIR or ANTENNA channels. If make a note of all channels that you receive and all of those listed in your TVFR that you do not receive. If you receive a channel clearly with your "old" antenna, then there is nothing that a new antenna can do to improve the situation. For those channels that you don't receive, you should determine why you don't receive them before you consider a new antenna.

It may be that the antenna is pointed in the wrong direction, the broadcast tower is too far away, you are suffering from multi-path signals, or some other reason that may or may not be solved by a different antenna.

Based on your TVFR, I doubt that you need a new antenna. You have numerous signals at your address what should be easily be receivable by the most modest of outdoor antenna and even by indoor antennas. If there some channels that you want but cannot receive, then do the following:

Describe your antenna by either exact model or give model of a similar antenna from Winegard or Channel Master.
In what direction is your antenna aimed?
List any significant signal obstructions and their directions from you near your residence. These include tall buildings, trees, etc.
List the call letters and RF channel numbers of the stations that you want to receive but cannot.

Electron · 5-Apr-2012, 10:09 PM

There is no such antenna as a analog antenna. A Tv antenna receives , analog , digital , FM , pulse modulation , and etc. , The Tv antenna can not tell the difference. Also the is no such antenna as a HD antenna. Antennas can Not tell the difference of , analog , digital , FM , pulse modulation , HD , Non HD , As a matter of fact Tv antennas flat out do not care.

Electron · 5-Apr-2012, 10:28 PM

Here is a Truth. As an example , UHF channel 14 , the smaller and less number of receiving elements there is less signal will be received. The bigger the antenna is , more receiving elements , the more signal will be received. Here is a truth , antenna amplifiers Do Not suck signals out of the air , antenna amplifier do not work like a vaccum cleaner. The truth is antennas with more receiving elements collect more signal , and antennas with less receiving elements collect less signal. A antenna amplifier can increase the strength of the signal that is received , but Does Not make or manufacture new signal.

Electron · 6-Apr-2012, 12:08 AM

Install a Winegard Hd7698P antenna above the roof aimed at about 160 degree magnetic compass. For more then 2 tv's connected , use a Channel Master CM3414 or CM3418 distribution amplifier.

fool · 6-Apr-2012, 2:24 PM

Thank you guys for the great replies and correcting me on the terminology.
I understand that there is no difference in 'analog' and 'digital' antennas - just change in station frequencies after the digital switch over.

I did some experimenting:
1. The cable from antenna looked old and ratty and was not full length. I connected another cable using a 4 way splitter lying around (in fact it looked like some specialty connector with three inputs for 'tv and sat input' and four outputs labeled 'to sat receiver'). This setup yielded 8 channels after scan.
2. Then I connected the cheap indoor antenna I got from monoprice without powering it. It yielded 7 channels after scan and some were different than what I got from roof mounted antenna.
3. Then I powered the antenna (it is advertised as low noise amplifier) and after scan I got 25 channels! I was under the assumption that indoor antennas don't need amplifier but for some reason my results were contradicting that.

I think my roof mounted old antenna is not good at UHF frequencies, visually looking at it, it has lots of big elements and not many small elements needed for UHF - maybe I am wrong. I will post a pic of the antenna when I get the chance.

Given that and after I receive my new samsung tv next week, I plan to do the following -

1. Get a new coax cable of full length, get up on the ladder and attach the new cable to existing antenna. Check and scan.
2. Put the cheap antenna on the mast (it is indoor/outdoor variety with weather shielding) and use the new cable. Scan with and without power.
3. If no good result from above setup, order winegard HD7698P and replace the roof antenna with that. Test without amp first and then try the CM3414 amp.

Any other suggestions?

Thanks again.

Electron · 6-Apr-2012, 4:02 PM

When the monoprice antenna is not powered that does not mean it is a antenna that is unamplified , it means that the amplifier is not working. The strong Tv channels of the tvfool radar report at the top of the green zone are so strong that they will be received no mater what is connected. There is a Real and Actual difference between a antenna with no amplifier at all , and a antenna that has a amplifier. Please do not spread misinformation , it's not helpful.

fool · 6-Apr-2012, 5:08 PM

Fair enough. Honestly, my intention was not to spread misinformation. I do believe that the cheap powered antenna is only good for people in vicinity of strong signal towers.

My first goal is to salvage the existing roof mounted antenna. I have to do a clean cable run right from antenna joint to the tv. I will report how it goes once I get the cable and time to do this job.

Dave Loudin · 6-Apr-2012, 5:24 PM

I think what Electron was trying to tell you is when you unplug the power from an amplified antenna, the preamp switches off, preventing signals from passing. That an unpowered indoor antenna behaved similarly to your unknown rooftop antenna leads me to believe that you still did not have a good connection between that antenna and your TV.

Most consumer TV antennas require a balun to match the coax cable downlead to the antenna. You did not mention how you connected to the antenna under test, so I have a couple of questions:

You are using coax cable throughout, not twin lead?
If you are using coax to the antenna, how did you connect to the antenna? If there is a balun involved, did you replace it, too?

fool · 6-Apr-2012, 6:08 PM

I see the coaxial coming down from antenna - no twin lead. So there may (or may not) be a balun at the top. I need to be home during daytime to climb up the ladder and inspect it.

I also suspect that the connection is not good and given the fact that they old, rusty, weather beaten, I am thinking of buying new cables and balun and replace the whole thing.

Any recommendation where to buy these?

Electron · 6-Apr-2012, 6:41 PM

The Tv stations in the green zone of the tvfool radar report are so strong that any kind of a antenna , even a piece of wire will receive them. It usually takes more then one advisor explaining for questions askers to understand that unpluging a powered amplified antenna Does Not make it in to a Non amplified antenna. The amount of misinformation out there is truly mind staggering. My evaluation is that 99% of the information that people have in their heads about Tv reception is stone cold wrong. I truly believe that people prefer misinformation and straight out lies and avoid the truth. If the computer is unpluged , does one expect to continue to surf the internet?? If a toaster is unpluged does one expect to get toast?? Home Depot and Lowes have coax and matching transformers (baluns).

fool · 6-Apr-2012, 8:35 PM

Thank you Electron and others, without your contribution and passion I would not be so informed.

I went out and took the picture of my existing antenna.

It does have a balun on top and antenna itself looks quite decent. Looks like the problem is downstream. I am going to buy some cable and connectors to reach the tv in clean fashion and report back.

My new tv (samsung 550) arrives monday or tuesday and should have the latest tuner. That might change the results too

frank55 · 6-Apr-2012, 10:57 PM

Quote:

Originally Posted by fool

Thank you Electron and others, without your contribution and passion I would not be so informed.

I went out and took the picture of my existing antenna.

It does have a balun on top and antenna itself looks quite decent. Looks like the problem is downstream. I am going to buy some cable and connectors to reach the tv in clean fashion and report back.

My new tv (samsung 550) arrives monday or tuesday and should have the latest tuner. That might change the results too

Bro That antenna seems very good for you area,go to Radio Shack and get a new balloon there is a golden plated one that costs more but it´s worth it and connectors,also god RG6 cable, i bought a new antenna and the balloon went bad in 3 moths
it gave me a head ache cause i never thought that the balloon that was new just got rotten inside,a mater of fact check my antenna link bellow that is very similar to yours after i remodeled it i live around Boston area a little farther north at Fall River and get most of the Chan from Boston,
i have also a indoor amp 24db and it has a turn switch that has - and + for more or less amplification, i have it closer to the receiver than the antenna and have to switch to minimun otherwise it cuts signal on some chan.

http://www.hdtvprimer.com/ANTENNAS/VU-190XR.html

Dave Loudin · 7-Apr-2012, 2:09 PM

As Electron said earlier, you can also get decent RG-6 cable and a balun at Home Depot and Lowe's. If you see a balun that was made in Japan, buy it (avoid gold plating)! Otherwise, no one balun stands out over another.

Your antenna is just fine for picking up Boston and Providence. It has a modestly wide range of azimuths where it is modestly to very sensitive to signals, so your aim does not have to be laser accurate for Boston. Since you have a VHF section, why not try to use it? I would start by aiming almost due south by a compass to get WNAC and WPRI. If you can get those plus all the stations in the green part of your report, then you're done. If you don't get them all, start stepping counter-clockwise 5 degrees or so until you get everything you want.

Good luck!

fool · 11-Apr-2012, 1:20 AM

Problem identified!

The cable run was the problem. Got some connectors from Home Depot, ran the cable to tuner. After scanning I got 35 channels including WNAC and WPRI! All crisp clear and no breakups.

Very very happy now

Thank you all very much for the prompt and comprehensive responses. This community is great.

In short, for anyone tuning in this thread: Get a decent rooftop antenna and never look back