Thread: 91XG or DB8e
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Old 9-Aug-2017, 1:34 AM   #2
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,516
Hello again, welkin

Quote:
Do you think I should change out one or both of the 91XGs to increase gain at these lower UHF frequencies in an attempt to make RF19/RF25 watchable,
The DB8E does have more gain than the 91XG for the low UHF channels according to the specs:



The DB8E must have both panels aimed in the same direction, which should be obvious. Also, both panels must be equally illuminated by the incoming signal, which might not be true. The 8-bay has a larger capture area than the yagi.
Quote:
or will I lose directional capabilities and get too much multipath interference?
The 91XG does have an excellent F/B ratio. It is not clear if it would make a difference with your UHF antennas aimed in different directions.
Quote:
Is there another option you would suggest?
A custom built yagi for the UHF low channels 14 - 36, in particular a loop yagi that has a horizontal loop for the driven element. It has superior rejection of off-aim signals. G0KSC calls his Loop Fed Array the Low Noise Yagi or LFA Yagi:
https://www.google.com/search?q=G0KS...k1.bNCN0I0-jCw

http://www.g0ksc.co.uk/2013-yagis/11...-lfa-yagi.html

The last resort would be a method of combining that avoids using a splitter in reverse as a combiner.
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Last edited by rabbit73; 9-Aug-2017 at 2:07 AM.
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