As a student, I had co-op jobs both with WLWT and with Pete Johnson, a
broadcast consultant who, with Carl Smith (CREI) wrote the FCC technical
Rules after WWII. I also toured the WLW and adjacent VOA site with my EE
class my senior year.
I'm pretty sure that the 500kW rig is no longer licensed, although they
were demoing it into a dummy load when I toured (1964). The dummy load
was something watercooled in front of the TX building. The modulation
xfmr sung as loud as many speakers. It's my understanding that the 500kW
rig was only on the air pre-WWII, but I could be wrong.
Broadcast stations are designed with two concerns, the dominant one
being groundwave coverage, which primarily depends on soil conductivity
over the entire path to the listener. One of the things I did in Pete's
office was plot field strength contours on aeronautical maps using
nomographs within the FCC Rules and the Commission's Ground Conductivity
maps.
The secondary concern, for stations licensed for more power, and
especially for what were then "Clear Channel Stations," was sky-wave.
And that's part of the other thing I did in Pete's office -- 4-5 of us
EE students sat around a boardroom table with slide rules, math tables,
and very large accountant's spreadsheets (think 20-30 columns) doing the
math to compute the patterns for every five degrees of Az and El for the
multi-tower directional arrays needed to squeeze new stations into a
band that had been full for more than a decade (probably from before WWII).
That adjustment to improve coverage of Columbus would have been for
nighttime. The WLW site is roughly 1/3 of the way between Cincinnati and
Dayton, a bit east of I75. Where I grew up in WV, WLW was our NBC
station, probably 100-120 miles as the crow flies, and we listened on a
pretty good table radio (my grandfather was an EE). This was the '50s.
In those years, WLW and (I think) WOAI were the only 50kW clears with no
one else on their frequency in the US. Something like 30-40 years ago,
clear-channel stations were far less exclusive.
73, Jim K9YC
On 1/5/2024 12:57 AM, Ken WA8JXM wrote:
Supposedly the half megawatt transmitter is still operational and licensed.
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