Topband: 2 Queations

Jim & Carolyn Kingsbury kingsburys at
Thu Mar 2 14:32:27 EST 2006

Has anyone measured or tried the tv cable splitters on the low frequencies 
(1.8 thru 10 Mhz)?  I wonder if they will work to combine 2 RG-6 phasing 
lines from pennant or flag antennas to a feed line to the shack.  The one I 
looked at said for 5 to1000 Mhz but I'm not sure if that rules out 1.8 Mhz 
or not.

Also I'm thinking of building the  K3LPL receiving filters described in an 
e-mail on this site several months ago.  What I'd like to do is build the 80 
and 160 filters, but build them with a 75 ohm input on one end and 50 ohm 
output on the other.  Frank says that the C1 and C7 capacitors are sized to 
act as voltage dividers to match the resonators to 50 ohms.  I'd like to 
change either C1 or C7 to match 75 ohms so I can use RG-6 from the antenna 
and RG 58 to the radio.  Can anyone tell me what size to make either C1 or 
C7 on the 80 and 160 meter filters to match 75 ohms.  I'd like to understand 
the theory and formulas to make this calculation if you can tell me wher to 
find the info.  Please respond to NW6S at so we don't clutter up a lot 
of peoples mail boxea with my simplistic questions.  Thanks in advance for 
taking time to answer.

73 Jim Kingsbury  NW6S (in western North Carolina if you need it). 

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