Australian TV Channel 0 (Zero)
Australia's Channel Zero (or "Channel Oh", as it is oft-called there)
was created in 1964 - causing the loss of the lower 2-MHz of the 6-meter
band in the country. The VK TV system uses 625 lines and 25 frames/sec,
with the FM audio 5.5-MHz higher than the video carrier. Thus a nominal
Ch 0 video of 46.25 (+/- any offsets) will have the sound at 51.75 MHz.
The poor showing of Solar Cycle 20, and its lack of US-VK 6-m paths
created little concern in W-land about this Australian "problem". However,
the much more intense Cycle 21 soon made their situation widely apparent.
Many times the path would be frustratingly solid at 50 MHz with nil signals
being propagated thru at 52 MHz.
My particular Brisbane Ch 0 audio clip was made using the 6-m antenna
(5-e Cush @ 23') feeding an Ameco Nuvistor preamp into an old SX-62 (as
my Swan 250 wasn't too good at slope-detecting the rather wide-band FM
TV audio). It must have been an intense signal for that system to render
as well as it did. It's a few seconds of John Wayne from the 1940 film
Three Faces West ("... no reason why you can't start being a pioneer
now ..."). For some more details on that film.
In Jul-Aug of that year I was fortunate to make a trip to VK4 to visit
relatives there. I took along an IC-502 and can readily attest to the
incompatibility of even hearing on the low-end of 50-MHz with a 100-kw
Ch 0 only a few miles away! (I did apparently get some ZL TV audio on
it once via a bit of winter Es when I was at apx 60-mi more distant.)
Even though I became VK4ZG while there, there were no 50-51 MHz transmit
privileges available to anyone, anywhere in VK at that time.
Anyway, I did make a visit to the Ch 0 transmitter-tower site (100-m
tower on a 300-m "hill" on the western edge of Brisbane). The vantage
from there to the ene (towards the US) was a clear shot to the Pacific
Ocean. I left a note there re my April reception and got a QSL letter
mailed to me in return!
In the years since much has changed. Many areas in VK were finally
permitted to use the low end of 50-MHz if there was no conflict with any
existing-Ch 0 service zone. That Brisbane Ch 0 moved inland by some
70-90 miles and tripled its ERP - adding stereo sound and shifting the
aud-vid carriers somewhat (and also creating a "regional" coverage zone).
There still exist some low-powered stations on as well.
Page last modified November 24, 1997