Antennas Direct ClearStream 4

scott784 · 6-Mar-2011, 7:00 PM

Yesterday, I installed an attic mount Antennas Direct ClearStream 4.

Fortunately, most of the signal is able to get out of the wall of my attic versus having to make a direct penetration through the roof shingles. It is working very well with one notable exception, WGHP RF35 Virt. 8.1 and Virt 8.2. This channel is occasionally pixelating to the point that the program cannot be watched.

The strange thing about this is the fact that WGHP is one of my true locals. The tvfool report shows the transmitter is only 32.6 miles from my house. Also, my attic antenna is facing about 180 degrees (approximately) and is having no problems picking up other stations which are very close to WGHP.

I believe this Fox affiliate may not be operating at full power (although their site seems to suggest they 'are' at full power). Maybe this is the reason for the problem. The interesting thing is the fact that I can pick up WAXN RF 50 Virt 64-1 and I am on the deep fringe for viewing that station (not one of my true locals).

I don't currently have this antenna hooked up to a pre-amp. Would that help? My guess is no since I am getting stations much further away (to include WAXN Virt 64-1) without issues at this time. I guess I will leave everything as is unless I learn otherwise. I appreciate any feedback.

PS The downlead coax cable from the attic is approximately 40 feet long.

http://www.tvfool.com/?option=com_wr...c77aecdc2fa091

GroundUrMast · 6-Mar-2011, 8:21 PM

Simple rule of thumb: If it doesn't work in the attic, try it outside.

Have you tried moving the antenna to different locations in the attic? And have you experimented with aim point?

(No, don't spend money on an amplifier.)

scott784 · 7-Mar-2011, 2:47 AM

Supposedly, this antenna is able to grab signals with a 45 degree radius on both sides of it's position. At least that's what a representative at Antennas Direct had to say about it.

I have it pointed at about 180 degrees which sends it down the A part of my roof line inside the attic. That seemed optimum when it was installed last weekend to allow the antenna to mainly penetrate through the wall of the attic--versus having to shoot directly through the roof shingles to get at the signals). I have a vinyl sided home so I am sure that helps too versus having an attic antenna with a brick exterior home.

Overall, this attic antenna is doing quite well. It's just the one local Fox affiliate which is at issue. Just about all of my true locals are southeast and the out of market broadcasts are southwest from my home. There are no breaks or splitters in the coax which runs just over 40 feet long from the antenna in the attic to television in my bedroom upstairs in my home.

As for an outside antenna, I've already got one of those (a Winegard 9095P) which I am using for the main tv in the living room downstairs. This outdoor antenna is slightly stronger since it's outside.....although again, my new attic antenna is doing quite well. It's just the one local Fox affiliate which is at issue when using the attic antenna.

So you don't think a pre-amp would help any on a 40 foot long coax from the attic antenna to the bedroom television? I wasn't sure about that.

PS In case you're wondering, I never wanted to split the signal on my outdoor Winegard antenna to reach the bedroom television upstairs for several reasons. That's why I've got a separate attic antenna for the bedroom television and of course that's what this post is about. Thanks for the reply.

GroundUrMast · 7-Mar-2011, 3:46 AM

It's possible to find 'hot' and 'cold' spots outside, more so in an attic. I really think you should try experimenting with placement and aim point before adding amplification to deal with the two or three dB of coax loss.

ADTech · 7-Mar-2011, 3:27 PM

Quote:

Simple rule of thumb: If it doesn't work in the attic, try it outside.

Can't tell you how many times I have to tell customers that!

The horizontal beam width of the C4 varies from about 31° at channel 14 to around 45° at 51. That's side to side, not center to each side for the -3 dB (half-power) points.

GroundUrmast is giving you the same advice I'd give if you called in.

scott784 · 8-Mar-2011, 1:03 AM

When you say 'aimpoint', I assume you are talking about angling the antenna to the left or right. As far as the position off the wall, it's probably about 4 to 5 feet. The space is very tight in the attic and it had to be placed where it could go between the air handler and the duckwork.

Again, the antenna is doing well up there. It's just the one local station, WGHP, that is at issue. I am not going to concern myself too much with it unless there's an easy way to fix it.

I know someone who will give me a free pre-amplifier to work with this antenna. That's why I was wondering if that would help. However, you have both advised against that.

As far as placing it outside, that is not a consideration in my particular situation. The costs of placing it outside would far outweigh any benefits. I do have a separate outdoor antenna for my main (downstairs) living room antenna. It doesn't pixelate or drop the signal on WGHP but that's only b/c I can rotate my outdoor antenna directly at WGHP when that station starts acting up. Obviously, an attic mount does not allow for continuous rotation so I had to find what appeared to be an optimum location for getting as many channels as possible (even if it meant the expense of one or two).

Unless there is an easy fix for WGHP, I am not going to worry too much about it. When this station is performing normally, the HD picture is as clear as any other station. However, WGHP, is subject to pixelation and drop outs from time to time. Again, all the other stations are doing fine (to include ones that are much further away from me than WGHP). Couple of questions here.

Are the signal meters (I've never had nor used one) a good tool to allow you to see what you are working with? I ask that question b/c I would think that a station that is available in perfect HD and gone the next is probably on the fringe of what it needs to start with. Second question, did you suggest 'not' using a pre-amp as a result of high temperatures that are expected during the summer months? I appreciate your replies.

PS These two televisions will remain on their own separate antennas and I don't want to tie one in with the other. This post is only about the attic install but I just mentioned the outdoor setup briefly since you mentioned going outdoors. Thanks.

GroundUrMast · 8-Mar-2011, 2:14 AM

If you have access to a free preamp, then by all means, give it a try. If it helps, great. If it overloads or acts like a noise source, you can remove it.

You are correct, when I say 'adjust the aim point', I mean turn the antenna to the left and right while checking the effect on signals from desired stations.

More rules of thumb:

When mounting an antenna, select a mounting location with the least amount of (anything other than air) between it and the broadcast antenna.
Keep the antenna as far as practical from metal objects.

If the attic wall is constructed of wood or vinyl, clearance is less an issue. If there is metal, including foil on insulation or wire mesh behind masonry or springy wire in plastic duct tubing..., ALL of the metal should be behind or to the side of the antenna by at least 4'... more would be better. That infers that some attics are simply going to be poor choices for installing an antenna. But it's still worth trying to find a 'sweet spot' if it will keep the antenna protected from the elements... in the attic, an antenna can last a lifetime.

scott784 · 9-Mar-2011, 12:45 AM

Yes, there are issues to consider, as you mentioned, about the placement of an antenna in an attic space. The next time I'm up there, I might do some more surveying to see if there is a sweeter spot. However, I am limited on space up there given the air handler, duct work, etc. Of course, the beauty of an attic install is the fact that it can last a lifetime as you mentioned since it is protected from the elements.

As mentioned, this antenna is doing great in the attic, with only one exception of the channel I've mentioned. I might give the pre-amp a try sometime. Are there any concerns that need to be given to an pre-amp installed in the attic? Obviously, we all know that attic temperatures can get very hot during the summer months. So if that is a risk factor, then I'd rather forget it.

As for signal meters, I've discovered that my bedroom Panasonic 37 inch LED has a built in meter. Now I am curious, is there a general (minimum) signal level that is needed to prevent pixelations and dropouts? If I knew the answer to this, it might help me with the reception on WGHP.

PS The outside wall in the attic space is only wood and vinyl siding. I am sure that has probably added to my success level on every other channel.

GroundUrMast · 9-Mar-2011, 3:59 AM

I'm always a bit leery of placing active electronics in a 120° F (or warmer) attic... (I suppose you could call that another rule of thumb.)

Each vendor implements signal metering as they see fit... 2 bars on one set means 'no problem', on another 'not a chance'. Some may be showing raw signal strength as determined by AGC in the tuner front-end, but many (I suspect) are showing some form of inverted error rate or other information derived from the de-muxing process. The problem is, none of the manufactures give any detail and they certainly don't offer calibrated measurements.

If you are seeing the signal indication bouncing or wandering from strong to weak, you can most times expect to see pixelation or loss of picture. Erratic signal strength or quality is a symptom (but not proof) of multipath. This is not an indication of weak signal strength which might be dealt with by amplification at the antenna, instead it suggests signals are arriving via two or more paths, and that at least one of the paths has rapidly changing electrical characteristics.

If you are seeing relatively stable but low meter indication on the problem channel, amplification might help. On the other hand, if the antenna is aimed at an air handler or duct or is mounted close to either, it could be de-tuned (made insensitive) to the channel you are having trouble with.

scott784 · 9-Mar-2011, 10:57 PM

Given the different characteristics, as you described, based on the model of the television, is there a standard signal meter that anyone can buy and attach it externally?

I am just curious b/c you'd like to think there must be a good signal meter that is universal in it's reading of the signal characteristics. Then again, I don't know much about this stuff so can't say myself.

GroundUrMast · 10-Mar-2011, 12:46 AM

Here is an example of a product aimed at the field service tech: Sencore SLM1476CM

Here is the least expensive option I have come across which claims to offer signal level measurement calibrated in dBmV: HDHomeRun Tech

I have not had hands on either of these products, so I'm not willing to recommend for or against.

I do own the 'non tech' version of the HDHomeRun. It offers relative Signal Strength, Signal Quality and Symbol Quality reporting. I'll add some screen shots of that feature in my existing thread Re. the HDHR

If I were charging customers for antenna installation and tuning, I would feel obligated to invest in equipment that was calibrated and verifiable against industry standards. Both to be sure I was delivering quality service and to be able to defend against the inevitable claim. However, for my own use and free assistance to others, I've been able to glean more than enough information from the signal metering built in to most STB's, DTVs and my HDHRs. (TV Fool is also a huge resource

)

scott784 · 10-Mar-2011, 1:30 AM

I like the price of your setup way better than the first two. To fully utilize it though, I'd have to learn about batch files and how to create them. Thanks for sharing the links.

GroundUrMast · 10-Mar-2011, 1:46 AM

To use the Silcondust HDHR, you do not need to write batch files or have programing skills.

Windows 7 Home Premium Edition ships with a fully functional Home Theater PC software suite ready to go.

The Open Source folks have a ready to install Linux Distribution packaged and well supported - Mythbuntu

I'm just cheap, and figured out how to make the basic functions work on my XP box...

scott784 · 10-Mar-2011, 2:16 AM

That's good news that Win 7 is fully functional with the HDHR without any skills needed with batch files, etc. You were quite ambitious to take on this project to get it going with your XP machine.

I've only got a single PC in the house (running Win 7) but don't find a need (currently) for streaming antenna signal to desktops or laptops. Having said that, I can see that it is a really good solution for many people.

That does bring up a question, would any LCD or LED television built within the past year or two have the capability to stream content if those televisions were hooked up (via ethernet cable) to the main antenna source? I am assuming the answer is no unless the LCD or LED has special built in software to allow such streaming with one of the devices, such as what you own.

We all know televisions are becoming more like traditional computers, within certain limits of course.

GroundUrMast · 10-Mar-2011, 2:54 AM

Since heading down the network attached tuner path, I've had less and less interest in the features available in new televisions. I see my self never buying another TV. Instead, I see buying or building HTPC's and connecting those to monitors with no built in tuners.

Perhaps others here are aware of new TV sets with the ability to stream out...

I think the powers behind HDMI and DRM will aggressively block such feature development.