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Old 26-May-2015, 3:31 PM   #2
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,753
Hi, Steve:

The CM2016 is still a good choice, but I'm not sure it is the best choice. The problem is the antenna beamwidth required to cover 50 degrees from 312 to 2 degrees, to avoid using a rotator.

Of course, if you want a rotator you need to be aware of the disadvantages:
1. extra expense
2. do you want to wait for it to swing around to the other direction?
3. if there is more than one TV, who gets to decide which direction?
4. you might need to rescan for channels after changing direction if your TV can't add a channel after scan
5. do you want to repair your rotator in the middle of January?

If you can't find an antenna with sufficient beamwidth, I think it would be easier to have a second antenna with an A/B switch to change antennas. Or, you could have a separate tuner for the PBS antenna and connect the output of the tuner to the TV A/V input.

When I look at the beamwidth specs for the 2016, they seem kind of narrow for what you want to do. You could try it, aiming between the two azimuths, but favoring CH 25.

http://static.highspeedbackbone.net/...0Datasheet.pdf

http://www.solidsignal.com/pview.asp?p=cm2016
click on specs

I also looked at the Winegard HD7694P:
http://www.solidsignal.com/pview.asp...negard HD7694P
click on specs

http://www.skywalker.com/catalog/Manuals/WIN1051.pdf

and I looked at the RCA ANT751
http://www.solidsignal.com/pview.asp...4&q=RCA ANT751
no specs given; not sure it has enough UHF gain for PBS because
Quote:
I'm really interested in also picking up channel 25 (WUNC) which is located at 312 degrees MagN, but my current antenna can't pick it up at all.
You might consider the Antennas Direct C2V. It has enough beamwidth, a little more UHF gain than the 2016, but not as much gain as the 7694 if the specs are accurate:
https://www.antennasdirect.com/store...-Complete.html

70 degrees beamwidth:
https://www.antennasdirect.com/clear...ntalplane.html

http://www.amazon.com/Antennas-Direc.../dp/B007RH5GZI

You don't need a preamp, it would be overloaded.



Interpreting Noise Margin in the TV Fool Report
http://www.aa6g.org/DTV/Reception/tvfool_nm.html

I'm a little confused by your tvfool report. It puts you in Willow Springs about 10 miles south of the transmitters, but Clayton is about 4.3 miles SE of the transmitters.

You have some very strong FM signals in your area, and you might need an FM trap/filter to prevent interference to your TV reception. See Attachment 3 for your location estimated from your tvfool report. Attachment 4 is based on Clayton.
http://www.mcmelectronics.com/produc...-FM-88-/33-341
https://www.antennasdirect.com/store...on_filter.html

My advice is based on no trees or buildings in the signal path. Trees really mess with UHF signals. See Attachment 2.

Quote:
I was getting ready to purchase a Channel Master CM2016 antenna and mount it on my roof.
The coax shield should be grounded with a grounding block that is connected to the house electrical system ground with 10 gauge copper wire for electrical safety. For further compliance with the electrical code (NEC), the mast should also be grounded in a similar manner to drain any buildup of static charge, but the system will not survive a direct strike.
Attached Images
File Type: jpg NMChartC.jpg (71.3 KB, 1582 views)
File Type: jpg Trees and UHF.JPG (89.7 KB, 1179 views)
File Type: jpg at_hikerTVF FMest1.JPG (119.4 KB, 1133 views)
File Type: jpg at_hikerTVF FMest2.JPG (118.4 KB, 1147 views)
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Last edited by rabbit73; 26-May-2015 at 6:21 PM.
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