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The establishment
of this site was the result of a combined effort between NFMRA and W1IMD. It
was first put on the air in the fall of 2001 by W1IMD. Although this site
is actually located in the town of Williamstown, it is referred to as
the Graniteville Site because of its close proximity the borough of Graniteville
which is located south of the City of Barre.
This
site was originally owned and operated by AT&T and was used as a microwave
relay station for many years. The site is presently owned by American Tower. The original call used at this station was W1AAK. That call was recently changed to W1JTB which previously was the call of a long time club member. Elevation at this site is 1970 feet AMSL.
The antenna support structure is a 238 foot self supporting tower. With
this elevation good UHF coverage is available northwest to Bolton and
south to Randolph along Interstate 89. Coverage is also good easterly
to East Orange and in some areas in and around Stowe and Hardwick. This station was
original and remains linked to UHF system on MT Washington.
During the summer
of 2002 the original Motorola MSF-5000 repeater was replaced with a General
Electric MASTR II station. Why replace a newer Motorola with an older
GE you ask? Well, the Motorola was destined to find a new home at a site
to be established in the future. When the MASTR II was installed a link
connection into the NFMRA system on Mt.
Killington was also put into operation. Later the same year new linking
equipment was reinstalled to get the linking system to Mt. Washington
back in operation. This gives the station the capability of being linked
in two directions and into two different UHF systems, individually or
in a combined configuration. The repeater frequencies used here are 444.600
/ 449.600 MHz. Two different CTCSS tones can be used to access the repeater
depending on user preferences. The system is normally operates configured so users
encoding a 110.9 Hz. tone allows repeater operation plus link access to
Mt. Killington and into the NFMRA system. Receive audio from Mt. Washington
will also be transmitted by the repeater in this configuration. A user wishing
to access the Mt. Washington system can do so by encoding a 71.9 Hz tone.
The controller switches the repeater over to the Mt. Washington system and disables the NFMRA link connection. The repeater
will remain in this configuration as long as there is usage on the system.
It will revert back to normal (Killington reconnected) after a period of
three minutes of non use. Rather than wait for the three minute time period to expire, switching back to normal mode can also be accomplished
by encoding a 110.9 Hz. tone from a user's radio. Verbal response from the controller will be "Washington link to monitor"
A Link-Comm RLC-1 Plus combined with a RLC-6 are used to interface the main repeater and both links units together. The RLC-1 controller is equipped with a "didga-talker" IC so it will respond verbally to commands that have been entered to it.
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To the left
can be seen a typical GE MASTR II station in an upright cabinet.
Located at the very top of the cabinet is a DB Products model dB
4076 duplexer. Next, barely visible under the duplexer is the Link-Comm
repeater
controller panel. Under the controller is the chassis which contains
the repeater receiver, transmitter exciter and power amplifier.
A preamplifier is used on the receiver. The transmitter is adjusted
to an output power level of about 50 watts. Next in line can be
seen the GE station power supply. Located on the right hand side
of the rack panel under the power supply is the link unit that connects
the repeater to Mt. Killington. This radio is a UHF GE Phoenix SX
mobile unit. The link unit used to connect to Mt. Washington is
an Alinco DR-235 Mobile unit which operates in the 222 MHz. portion
of the spectrum This unit is not visible in this picture. Under
the link unit rack is a regulated 13.5 volt power supply that supplies
power to both link units and also acts as a redundant supply for
the repeater controller. Transmission line to the repeater antenna
is 7/8 inch heliax cable and the antenna is a dB Products DB-404.
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Here
we can see almost all of the 238 foot tower and the roof of the building
as it would be viewed looking in an easterly direction. The now
unused periscope microwave antennas are still mounted on the very
top of the tower. The repeater antenna is barely visible between
the two microwave antennas.(Up dated 09/09) The Micro- wave antennas shown in this and the next picture have now been removed.
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Here is a closer
view of the very top of the tower. A better view of the repeater
antenna can be seen in this picture. In another sense of the word, one might
call it a lightning rod instead of an antenna.
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