[BC] WLS Tx History Update

[peterh5322 at rattlebrain.com]

> WGN Chicago  has a 10 kw Tx in an out building as transmitter 3.  It
> solved a fire protection issue having a transmitter in a second building.
> Main building suffers fire damage backup survives and gives a Plan B
> recovery.

All Chicago former Class I-As have second antennas.

I believe WLS was the last to construct theirs, and it was constructed as
199' and with no lighting.

The other Chicago former Class I-As had their auxiliary ND antennas long
before WLS's.

> For WLS the Tx 3 lives with no power or antenna path.  One time both 50's
> were down and the back up came into action as the only working
> transmitter.  One time in 22 years.  It does stop the phone from
> ringing...Alway asking how long will we be off?  Answer,  A lot short if
> you stop call me. Some power is better than no power.

According to Warren (off-List communication), their 199' second antenna is
capable of 50 kW.

KFI's very short second antenna is capable of only 25 kW, but KNX's rather
taller (135 degrees, about 340 feet) second antenna is undoubtedly capable
of 50 kW.

KNX had no second antenna until after a terrorist felled its ca. 1936
antenna in the 1960s, after which a 195 degree replacement was installed,
and also a 135 degree second antenna. As KNX was originally on 1050 (and
WLS was originally on 870) the old mains "grew" in effective height with
the 1941 forced change in frequency.