Montanavision Media Inc.
Client Since 2006.
KGPR, Great Falls
The old tube-type Wilkinson transmitter didn't much care what kind of load
was connected to it, but the new Harris HD RadioTM Transmitter
complained from the moment we turned it on. The Board approved additional
work to determine the cause of the problem and develop a solution.
We started by inspecting the antenna and coaxial cable in-place on the tower.
Having a tower lighting beacon this close to the top bay is not good,
but we could not move the antenna nor move the beacon.
Next, we arranged to have Colton Tower Consultants remove the antenna from the
tower, so it could be more closely inspected and certain critical components
could be refurbished. Shively Labs recommended that we replace the internal
bullets, o-rings, hose clamps, and line hardware. This is the top bay after
removal of the radome.
The matching transformer at the bottom of the antenna showed several longitudinal
stress cracks in the upper horizontal section. We believe these were caused by
water freezing inside. They do not appear to completely penetrate the shell.
The Shively 6810-4R antenna back in place on the tower: a bit straighter,
and tuned to bring the reflected power down to barely-measureable levels.
KGPR Transmitter Page, 2006.
KGPR Studio Page, 2006.
KGPR Studio Move Page, 2007.
KGPR New Studio Page, 2008.
KGPR Web Site.
Montanavision Media Home Page.
This page updated 14-Mar-2016.