Clearstream 2 Pre-Amp or Distribution Amp?

drick · 26-Jul-2011, 5:09 PM

All, enjoy the forum and thanks in advance for the help. I have installed a Clearstream 2 antenna in my attic and want to get some advice regarding the use of a pre-amp or a distribution amplifier. I would like to send the signal to 5 TVs. Here is my report along with other specifics:

http://www.tvfool.com/?option=com_wr...03f3eda18892a3

Antenna mounted in attic and approximately 25 feet high
Cable runs from antenna and then downstairs with no splitters approximately 30 to 40 feet of cable
I have the cable hooked up to a 4-way distribution amp that I picked up at Home Depot for $15
4-way Distribution amp feeds 5 TVs from that point; 3 outputs to 3 TVs (approximately 30 feet cable each) and one output feeds 2 TVs with one splitter (another 30 feet of cable)

The 2 newer TVs with digital tuners have great reception and the signals in my area are really strong. However, I have 2 primary issues:

The PBS station (4.1) does not come in as strong as I would like on any of the TVs
The other 3 TVs are older and I've only tried the convertor box on one. That one TV has a VERY hard time keeping the PBS station AND does not pull in near the number of channels as the newer TVs (20 stations vs. 35)

With this set-up from above, do I need to be using a pre-amp or is the distribution amplifier the way to go? Or, do I need both?? Is the distribution amp that I have (which again, was only $15) inadequate? What heading should I have my antenna pointed towards??

Any and all advice, input or suggestions would be greatly appreciated. I've tweaked and tweaked and my wife is running out of patience!

Thanks.

Tower Guy · 26-Jul-2011, 11:22 PM

Quote:

Originally Posted by drick

[*]The PBS station (4.1) does not come in as strong as I would like on any of the TVs

You're barking up the wrong tree.

4.1 is weak because it's probably not in the main beam of the antenna. A mis-aimed antenna causes multipath in addition to a weak signal.

Consider a second antenna for PBS.

drick · 26-Jul-2011, 11:24 PM

Thanks Tower Guy and that might prove to be most straightforward solution. Any recommendations on an antenna? How do I go about connecting the antenna together?

ADTech · 26-Jul-2011, 11:31 PM

Before getting to the amplifer question...

We do need to recognize that the C2 has a defined reception pattern as shown on the back of the box and here: http://www.antennasdirect.com/clears...ntalplane.html That makes the aiming direction of the loops important. Looking at your TVFool plot, it shows that you have stations "all over the map" from numerous directions. While you may find an aiming direction what makes everything happy, it will be a trial and error effort. The C2 does have a generous 70 degree beamwidth for its primary lobe, but when signals arrive at the back or sides, they will often be delivered to the tuner is a less than usable condition. Capabilities do vary between various tuners, so be prepared for some variations. Some are more sensitive to weak signals, some are more capable at correcting multi-path.

Since we don't know which direction you have the antenna aimed nor which stations are on your "must have" list, we'll defer the amplifier question. I don't see a need for a pre-amp, but a distribution amp *might* be helpful. If you can install a barrel splice in place of that amp/splitter and test that converter box, that would tell us how it responds to a passively delivered signal. Personally, I'm not optimistic that you'll be able to find a single aiming direction that works for everything UHF on your chart, especially in an attic.

Also, don't obsess about the meter readings. The threshold for success is simply reliable reception, not a maximum number. If it isn't breaking up during both mild and severe conditions, you're done.

John Candle · 27-Jul-2011, 12:58 AM

Read and understand about , REAL Digital Broadcast Tv Channels , Virtual Digital Broadcast Tv Channels , Analog Broadcast Tv Channels , http://forum.tvfool.com/showthread.php?t=695 , example - WUNC-TV , the real channel is UHF 25 , the virtual channel is 4.1. For antenna aiming I suggest aim the antenna at about 130 degree magnetic compass. This should get the tv stations in the magnetic compass directions of , 306 , 181 , 125 , 71. I also recommend have one tv connected as a test , No amplifiers or amplifier power supplies of any type or kind. None. Coax is connected from the antenna to the tv.

John Candle · 27-Jul-2011, 3:29 AM

The loops are the front of the antenna , the front of the antenna will be aimed at about 130 degree magnetic compass. This is a Test to see how strong the signals are in the attic in the directions of , 181 , 125 , 71 and if WXII-DT 31 NBC and WUNL-TV 32 PBS at 306 magnetic compass that are very strong stations can be picked up through the back side of the Tv antenna.

John Candle · 27-Jul-2011, 3:45 AM

Does the house have a metal roof or metal backed insulation on the inside of the roof??

drick · 27-Jul-2011, 4:23 PM

John, the roof is just your standard asphalt shingles. The roof has a high pitch and the insulation is on the ceiling and not in the rafters.

John Candle · 28-Jul-2011, 3:47 AM

I recommend use a Channel Master CM3418 eight way distribution amp. Put 75 ohm terminators on any unused outputs of the distribution amp. I Strongly Suggest move the antenna to the outside for much improved reception , above the roof , up at the top. Also as a experiment , I suggest order a Winegard MS 1000 omnidirectional antenna and mount it above the roof in place of the CS2. Please note that omnidirectional antennas are not 100 % omnidirectional , might need to turn the antenna to find the spot that receives the most Tv stations in every direction.

Tower Guy · 28-Jul-2011, 1:20 PM

Quote:

Originally Posted by drick

Any recommendations on an antenna? How do I go about connecting the antenna together?

Any UHF only antenna is fine for 4.1. You can combine the antenna with a Jointenna for channel 25 if you can find one or Tinlee will custom build one. The cheapest option is an A/B switch.

An alternative is PBS from WBRA on channel 3. You can combine a low band VHF antenna (Y5-2-6) using a cheap HLSJ combiner. But a low band antenna will be large, and your signal strengths mean an outdoor install.

drick · 28-Jul-2011, 2:12 PM

Thanks John. I pointed the antenna towards 130 degrees last night and made sure my cable run was directly to TV. Rescanned the channels and it did help channel 25 come in better (around 70% on TV signal meter) and I didn't lose channel 31 which sits at 298 degrees (which I was afraid might happen). I hooked two more TVs back to the antenna via a splitter (did not hook up the distribution amp), rescanned and everything seems to be ok. However, this morning, channel 25 signal could not be found and the channel 31 was having issues as well. My other required channels of 51, 29 and 35 came in strong as they always have.

Any idea on why this might have happened? Am I going to basically have to deal with not getting the PBS channel (25)? It is the over 40 miles from me, so that might just be an issue I'll have to deal with.

John, you had suggested I use the Channel Master distribution amp. I had an amp on there, but as I said, it was a $15 deal from Home Depot and nowhere near the quality of the Channel Master. However, I can't find a local outfit that sells that brand and will have to order over the internet and can't easily return if it's not helpful. If you think that might be beneficial in my setup then I'll go for it.

I know the roof is the ultimate answer but I don't want to install anything on my house.

drick · 28-Jul-2011, 11:20 PM

Update on channel listing. Hopefully somebody can give me an idea on a heading to point the antenna.

I have been picking up RF channel 32, virtual channel 26.1 which is a PBS station with an antenna at 306 degrees and 31.6 miles from my location. The 4.1 channel has the same feed as the 26.1, just a different tower. With that information, should I leave my antenna pointed toward 130 degree?

John Candle · 29-Jul-2011, 1:47 AM

I suggest move the antenna to the outside above the roof. Outdoor Tv antennas receive the best when the Tv antenna has elbow room. Outdoor Tv antennas receive the best when the Tv antenna is not being crowded. Outdoor Tv antennas receive the best when the Tv antenna has nothing blocking the reception. Outdoor Tv antennas receive the best when the Tv antenna has a clear view of the transmitting antennas. All the easy to receive channels are LOS = Line Of Sight. The Tv antenna will be very happy when the Tv antenna can see the transmitting antennas. Federal Law is that Yes you can install and use a Tv antenna outside , and Yes the antenna can be installed and used in a place that gives the best reception , http://www.fcc.gov/mb/facts/otard.html