BC-DX 841 04 Jan 2008 Private Verwendung der Meldun

(Carlos Goncalves-POR, wwdxc BC-DX TopNews Aug 11)
CKZU 6160 KHZ, VANCOUVER, BRITISH COLUMBIA by Harold Sellers. DURING our
vacation in July we spent several days in Vancouver. Before departing for
the West Coast I had determined to try to locate the transmitter site of
the CBC's shortwave outlet, CKZU, which has operated on 6160 kHz for many
years. This would complement a similar successful search I conducted a
number of years ago, when CKFX also operated on 6080 kHz from Vancouver.
A Google search found a number of reports of the location and coordinates
of the site. These confirmed what I knew from DX reports over the years;
that the site was in the City of Richmond. Richmond is built on the Fraser
River delta, south of Vancouver. It's very flat land. It's also where CKFX
had been located until its closure (although the actual sites had been
several miles apart).
Google Earth was used next to try to spot the antenna towers from space.
Knowing that the site was in the old town of Steveston, which is now part
of Richmond, I simply entered Steveston, BC into the search criteria and
then scanned the landscape west of the town, beside the ocean.
Quickly I spotted the shadows of the towers (see illustration at right).
The towers of CBU, 690 kHz, were easy to see and there were also some
shorter towers. I suspected these were for CKZU. The coordinates were 49
08'21"N and 123 11'44"W. On one of the many sunny and warm days of our
vacation we drove through Richmond to Steveston Road and headed west.
Steveston Road ended at a small parking lot serving an adjacent cycling
trail built upon a berm. Climbing the berm, we could see a building and
several antenna towers a few hundred meters to the north. Walking to the
building, the photographs on this issue's cover show what we saw.
The transmitters are housed within the building shown. The antennas are
located on the flat floodplain running from the berm to the ocean. Cattle
graze on the grasses growing here and there are numerous old logs lying
about, signs of past floods, which swept them ashore. To the east of the
berm lie the subdivisions of modern-day Richmond. Again, you can see all
of this urbanization in the Google Earth image.
CBU uses four tall guyed, metal masts. Raised wooden walkways carry the
feedlines and allow technicians to walk to the towers. The CKZU antenna is
located a short distance from the building and can be easily walked to, if
the ground is not flooded.
The antenna is a folded dipole supported by two wooden poles. A passive
director is strung between two identical poles. The dipole is obviously a
halfwave in length, which for 6160 kHz would be in the neighbourhood of 75
feet. Folded dipoles have a high impedance, thus the radiator is fed by
open-wire twin-lead. This feeder rises from a short pole below the
antenna. 75 ohm coaxial cable comes from the transmitter to a balun on
this pole.
The radiator and director elements of the antenna are broadside to a
northerly direction. Thus the antenna was constructed to radiate the
signal up the coast of British Columbia. The passive director element
concentrates the signal even more so in this direction.
It was apparent to me, that over the years, the antenna elements have
sagged a bit. Some of the guy wires on the wooden poles are very loose.
This, plus the passage of time and the soft ground have probably resulted
in some leaning of the poles. The sagging antenna may actually help some
signal from CKZU radiate off the sides, benefiting listeners to the east.
Pictures taken and the walkabout completed, my mission was accomplished