[BC] Franklin

[Rob Atkinson]

So I guess someone had to climb the tower to adjust the L network?  How 
often did that have to be done?  Sounds like a great antenna but a pita.  No 
free lunch.

thanks

Rob Atkinson

From: PeterH5322 at aol.com
Reply-To: Broadcast Radio Mailing List <broadcast at radiolists.net>
To: broadcast at radiolists.net
Subject: Re:  [BC] Franklin
Date: Wed, 20 Jul 2005 21:30:10 EDT


 >Franklins can be driven by a single feedline branching near the ~center
 >insulator to drive the bottom of the upper section and the top of the 
lower
 >section (if the proper phasing network is used), but that does not make
 >them the equivalent of a center-fed dipole.

The WOAI 120 over 120 was insulated at the base.

There was an adjustable capacitor across the base insulator. This
capacitor was designated "Base Tuning Capacitor".

The radiator was center fed with the outer conductor of the coax being
bonded directly to the top of the bottom section, and with the bottom of
the top section being fed across the sectionalizing insulator from the
center conductor of that coax through an "L" network. This network was
designated "Tuning Network".

There was an ammeter in the "Tuning Network", which was normally shorted.

There was an ammeter at ground level, along the path of the coax from the
Tx to the radiator. On the Tx side of this ammeter was the notation
"Antenna Resistance Measured Here".

Presumably, a similar system is being used at WHO (180 over 120), KSTP
(179 over 179) and KFBK (180 over 180).

I suspect a different system is being used at WOC.

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