Help in fringe area in VT

[Stovepipe]

My apologies for the long-winded post, but I wanted to provide enough info.

Here's the report:

http://www.tvfool.com/?option=com_wr...d24343a0ff03ca

I'm really just interested in getting the 3 main network channels to the N, and the 2 to the S.

Here are the details. We had a large roof-mounted rotatory antenna that was 20 years old. Reception was pretty good, but stations to the south (PBS) did not come in all the time. Since the old antenna was missing several elements and the coax was also 20 y.o. I decided that a new antenna and RG6 cable could only improve reception. I was wrong. This is the antenna I bought:

http://www.channelmasterstore.com/Di..._p/cm-3018.htm

It is slightly smaller than the old one. Has a 100' RG6 coax, only 1 TV (although I'd like to have 2 TVs). Reception was very spotty at first, and only the 3 stations to the N (ABC, NBC, CBS) came in. I then added a pre-amp, which improved the reception of those 3 stations, until recently when they started dropping off the digital cliff every so often and I'd get a 'no signal' response, sometimes lasting for days. This seems to happen when it gets hot and humid or rains.

My guess is that I need a larger antenna, but before I sink another $150 into it I wanted to get some advice from the experts. Any chance that the pre-amp is interfering with the signals? I've tried it with and without the pre-amp when I don't get a signal and it hasn't made a difference.

What are the chances that raising the antenna another 2 feet would make a difference? It is now about even with the peak of the roof (which may be why we have trouble getting signals from the south since the roofline is in the way??).

Thanks!

[GroundUrMast]

A 2' change in height may produce a significant change in signal quality. It's an often overlooked fix that may cost only a bit of time and effort.

When you click on the call sign of a station listed on your TV Fool report, a path profile is displayed. It's clear that you are in hilly or mountainous terrain which is blocking your line of sight to the north and south.

The CM3018 is quite a bit of antenna, but you need all the UHF gain you can get. It also has Low-VHF capability that serves no purpose at present. This includes FM reception which could be a potential source of interference. If I was in your situation, I'd likely end up with three antennas above my roof... and no rotator.

Aimed north would be an Antennas Direct DB8E and an Antennacraft Y10713 both connected to an RCA TVPRAMP1R set for separate UHF and VHF input.

Aimed south, I'd have another DB8E and TVPRAMP1R set for combined input or an Antennas Direct PA-18 if there are no strong FM signals nearby. This would cable separate of the north antenna array, terminating in a set top axillary tuner that connects to an auxiliary input of my TV.

[Stovepipe]

Thanks for the reply. Three antennas is very unlikely to happen.

Any suggestions if you had to go with a single mast mount? Most of the channels I'm interested in are UHF, correct?

+=>

The signal strengths are Very Weak Signal Strengths at your reception location.

To see if signal strengths improve at higher antenna heights please make and post 2 more tvfool reports , 40 and 60 feet above ground.

Do not delete the first tvfool report of 25 feet above ground.

[Stovepipe]

Thanks for the suggestion. Here they are:

40' -- http://www.tvfool.com/?option=com_wr...d243bba0863e0f
60' -- http://www.tvfool.com/?option=com_wr...d243e69eff9286

[GroundUrMast]

The signal conditions don't appear to change significantly as you increase the mounting height. However, the terrain that blocks your line of sight toward the transmitters makes the prediction less accurate.

If you opt for a single mast mounted antenna, I would use a Winegard HD7698P or Antennacraft HBU-55. To make full use of the antenna would require that you use a rotator which can add complications... If more than one TV is connected, there will be times that the antenna is pointed the wrong way for one or more viewers. Many tuners lack the ability to manually add or 'add-scan' channels. Those TV's would require a full channel scan each time the antenna is turned.

What options do you see available to you for alternate mounting locations and added height? I'd try experimenting with these before changing antennas.

[Stovepipe]

Thanks for the suggestions on antennas. The rotator complications are not a big deal, as we almost never have 2 TVs on at once now that our youngest is away at college. I will try adding some height first -- realistically I can only get the antenna up another 2-3 feet higher, but that will be enough to clear the roofline, which may eliminate some interference (at least that's my hope). If that doesn't help I will invest in one of the antennas you suggest.

It still puzzles me how my 20-y.o. antenna with missing elements and 20 y.o twin-wire leads got better reception that what I have now with brand new RG6 coax and a pre-amp.

For what it's worth, I have a Channel-master Titan II pre-amp. Is it worth the $60 I paid for it?

Again, thanks for the input -- I appreciate this forum.

[GroundUrMast]

Clearing your roof-line is an excellent 'next step'.

There are two models in the Titan series. Is your a CM-7777 or CM-7778? The CM-7778 is a medium gain design that can tolerate the presence of some stronger signals. The CM-7777 is easily overloaded when a strong signal source is present. Your TV Fool report doesn't show any strong TV signals, but an FM station may be present. (You can use the FM Fool tool to investigate.) Both amplifiers include a switchable FM filter (trap). I would enable the FM filter unless I intended to use the antenna to receive FM and TV via one antenna or, if a signal on real CH-6 is present. (I normally suggest keeping TV and FM antenna systems separate and independent. The FM band and real CH-6 are adjacent frequencies and CH6 reception is often reduced when an FM filter is used.) On the CM-777X, the FM switch is accessed by removing the cover, so you may want to verify you have enabled the FM filter (to block most of the FM signal from entering the amplifier).

Is the CM-777X worth $60? Perhaps... But I am very impressed with the performance of my RCA TVPRAMP1R that was less than $30. The RCA is tolerant of stronger signals, has relatively low noise and distortion, includes a switchable FM filter, two inputs (one for UHF and the second for an optional separate VHF antenna) and enough gain to drive hundreds of feet of coax.

The bottom line is, if you have no strong signals present, either of the CM-777X models is a good choice from a technical perspective. If there are any strong signal sources, the CM-7777 would be at risk of overload and the CM-7778 or similar competing preamp would be a better option.

[Ben Myers]

Originally Posted by Stovepipe

My apologies for the long-winded post, but I wanted to provide enough info.

Here's the report:

http://www.tvfool.com/?option=com_wr...d24343a0ff03ca

I'm really just interested in getting the 3 main network channels to the N, and the 2 to the S.

Here are the details. We had a large roof-mounted rotatory antenna that was 20 years old. Reception was pretty good, but stations to the south (PBS) did not come in all the time. Since the old antenna was missing several elements and the coax was also 20 y.o. I decided that a new antenna and RG6 cable could only improve reception. I was wrong. This is the antenna I bought:

http://www.channelmasterstore.com/Di..._p/cm-3018.htm

It is slightly smaller than the old one. Has a 100' RG6 coax, only 1 TV (although I'd like to have 2 TVs). Reception was very spotty at first, and only the 3 stations to the N (ABC, NBC, CBS) came in. I then added a pre-amp, which improved the reception of those 3 stations, until recently when they started dropping off the digital cliff every so often and I'd get a 'no signal' response, sometimes lasting for days. This seems to happen when it gets hot and humid or rains.

My guess is that I need a larger antenna, but before I sink another $150 into it I wanted to get some advice from the experts. Any chance that the pre-amp is interfering with the signals? I've tried it with and without the pre-amp when I don't get a signal and it hasn't made a difference.

What are the chances that raising the antenna another 2 feet would make a difference? It is now about even with the peak of the roof (which may be why we have trouble getting signals from the south since the roofline is in the way??).

Thanks!

You might try angling the antenna upwards slightly. The new antenna has a corner reflector Yagi UHF section, which is highly directional in the vertical plane as well as horizontally and it may simply be pointing too low on the horizon.

[Stovepipe]

That's an interesting idea. I can't quite visualize how I would tilt it upward, as the antenna is mounted on a round pole with U-clamps, and the mast is mounted into the rotator. I don't think the U-clamp connector has any flexibility in the vertical plane other than perpendicular to the mast pole.

[Ben Myers]

Originally Posted by Stovepipe

That's an interesting idea. I can't quite visualize how I would tilt it upward, as the antenna is mounted on a round pole with U-clamps, and the mast is mounted into the rotator. I don't think the U-clamp connector has any flexibility in the vertical plane other than perpendicular to the mast pole.

Well, even a few degrees might help. I have an antenna similar to yours and it has a little play in the vertical.

[Stovepipe]

Great. I'll give it a try, thanks.

[Stovepipe]

Here is the FM report
http://www.fmfool.com/index.php?opti...pper&Itemid=29

I have the CM-7777 (the higher gain model). I did not change the FM filter from the factory settings, which according to the instructions, is set for TV-only (FM trap "in").

I suppose I should have confirmed the FM filter setting before installing it, but it doesn't look like there are any super strong FM signals anyway. Probably worth checking the setting next time I'm up on the roof.