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Old 20-Dec-2011, 4:40 PM   #7
GroundUrMast
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Join Date: Oct 2010
Location: Greater Seattle Area
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The Antennacraft product line is reputable and the manufacturer provides reasonably helpful performance documentation. http://www.antennacraft.net/pdfs/HDMS9100.pdf

Based on this published information, I'm lead to believe that the net high-VHF performance will be a negative number. The antenna gain is spec'd at -6.4 dBd and the integral amplifier NF is 3.7 dB (H-VHF band). At best I expect the result will be a reduction of received NM by about 10 dB.

WJW, real CH-8 is predicted to arrive at a NM of 18.4 dB. Therefor the expected net NM at the output of the antenna will be about 8.4 dB. That's begging for unreliable reception results IMO. And this does not consider how much edge path fading and multipath will be present.


Contrast this against the performance of the HD7694P. Conservative interpolation of the manufacturer's performance specifications puts the gain at about +8 dBd on channel 8. Using no amplifier, there will be no reduction of net NM due to amplifier noise. For WJW, the expected net NM will be 18.8 + 8 = 26.8 dB. I think adding a net of 18 dB NM significantly improves the chance of reliable reception of WJW.
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Last edited by GroundUrMast; 20-Dec-2011 at 4:55 PM.
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