[BC] Re: Early Rigid Coaxial line 2

[tg@btsg.com]

Ron Cole writes: 

> In 1981 I rebuilt a 12 Bay RCA Batwing TV Antenna,
> Seems we bought the new feed lines from Dielectric.
> If memory serves they were 7/8" aluminum Semi rigid lines that bolted to the
> elements and attached to a power splitter. Seems there were 6 Bays per Power
> splitter. The Power splitters were 3 1/8" and the transmission lines up the
> tower were 6".
> All of it was 51.5 ohm stuff, from the Transmitter to the Antenna. 
> 
> 
> Ron

The lines were phasing lines, and were cut to a specific length for each 
bay.  It was my job to open up the patch on Sunday nights and using a 
wheatstone bridge, measure the resistance of the East-Wset, and North-South 
antennas of the Bat-wing and log the measurements.  By tracking these 
measurements weekly, we were able to determine when a phasing line was going 
bad and needed to be replaced.  This was on a 2000 foot tower on channel 3. 
And yep..it was 51.5 ohm line.  Our lines up the tower were 3 1/8 rigid. One 
for each set of bays (2 in all). 

Getting a tower crew that could properly lace the long phasing lines back 
into their position was a feat sometimes, as they had to be looped  back and 
forth to take up the slack so they would fit, and improper installation 
could lead to early failure. 

Tommy Gray