ECUADOR
Update from Ecuador NASB meeting in Elkhart-IN-USA, 2007
The first speaker after lunch was Brent Weeks, missionary engineer at HCJB
Global in Quito, Ecuador. Weeks explained that the DRM transmission from
Quito was currently in the most robust mode that permits AAC operation. He
said that there are lower bit rate, voice quality codecs that are even
more robust, but they are not good for music transmission.
Brent Weeks has worked at HCJB in Quito for six years. He showed a slide
of HCJB's transmitter building, which is in Pifo at an altitude of 8400
feet above sea level in a valley between two ridges of the Andes
mountains, some 20 miles (about 30 kilometers) east of Quito. Mount
Cotopaxi, the highest active volcano in the world, could be seen in the
background of the photo. HCJB has three HC-100 100-kilowatt transmitters
at this location, plus two more at HCJB Global's shortwave site in
Australia.
The antenna field in Pifo includes an antenna directed to Brazil, another
for South America and northwestern North America, another for 49-meter
band regional broadcasts to the Andes corridor, a cubical quad antenna
used for broadcasting to Europe in the 13-meter band and a steerable
antenna with a parabolic reflective curtain which can cover 180 degrees
almost due west to due east. The steerable antenna dipole rolls around on
a track.
Airplanes regularly fly by the site en route to the Quito airport, which
is located in what is now the middle of the city. The Quito authorities
have decided to build a new airport further from the city. "The location
that has been chosen," Weeks said, "means that our antennas are too high.
We've taken down 18 towers already, and we have more to go." The site will
eventually have to be closed.
HCJB has looked at various options for replacing Pifo. One option is to
build another transmitter site in the mountains. But HCJB has its own
power station nearby, and if it continues to use the power from that
station, the options for a new location are limited.
Weeks said that there has also been a change of philosophy in HCJB
Global's mission in the last several years. The focus is now almost
exclusively on transmissions to Latin America in Spanish, Portuguese,
Quichua, Quechua and German for the Mennonite populations in Paraguay and
Bolivia. Gone are HCJB's longtime broadcasts beamed to Europe, Asia and
the South Pacific. The only transmission beamed outside of Latin America
now is German to Europe. Broadcasts to these other regions have been moved
to HCJB-Australia and rented facilities like VT Communications in the UK.
[and DTK Wertachtal 6015 at 1700-1800 UT non-dir 100 kW HCJ too, wb.]
At this point, Weeks went back to the live audio of the DRM transmission
from Quito. The station had just made a switch, timed especially for the
audience at the meeting in Elkhart, to 64 QAM, producing a parametric
stereo signal. The signal-to-noise ratio was 16-17 dB. There were a few
dropouts, but Weeks considered that the signal was doing fairly well
considering they were only using between three and four kilowatts of power
from a Siemens 10-kilowatt linear analog transmitter. After a few minutes,
the signal went back to a 16 QAM mode for a more robust broadcast. HCJB
had been changing the technical parameters of the DRM broadcast throughout
the day. "You need agile scheduling of transmission parameters," said
Weeks. "We'll go to a less robust, higher quality audio later in the day
as propagation improves."
Meantime, a few of HCJB's engineers in Ecuador, including Brent Weeks, are
working with the Global Technology Center in Elkhart on DRM development.
One of those areas is the central control system that drives and tells the
servo-motors what to do. "It needs to be upgraded for DRM," he said. The
station has recently done DRM test transmissions for the SWL Winterfest in
Pennsylvania, the National Association of Broadcasters Convention in Las
Vegas, and the NASB/USA DRM meetings in Elkhart. Other tests are being
beamed to Germany. "We are getting good reports for the middle-of-the-day
broadcasts to North America," Weeks said.
(NASB Newsletter)
