Vertex VXR-5000 - AC Power Supply Voltage Selection; Equipment Location; Operation; Installation

VXR-5000
Installation
Repeater operation without a duplexer re-
quires
that two antennas be inslalled, one for
receiving and one for transmitting, so that the
receiving antenna does not absorb energy
from the transmitting antenna. ~here are a
number of ways to do this, depending on the
TX/RX frequency separation, and on the lo-
cation
available for antenna mounting. If a
duplexer is used, a single antenna suffices for
both transmitting and receiving. If using a
reduced-size duplexer, a six-c avit y model
(minimum) is recommended.
Regardless of the above choice, it is of
paramount importance that the antenna(s) be
mounted as high as possible, and in the clear
as possible,
preferably within line-of-sight to
all
repeater users. ?urthermore, losses in the
feedline(s) must be minimized, so the
feedline(s) should be high quality, and as
short as possible. :a a long feedline is neces-
sary, use coaxial hard line cable to reduce
losses.
Repeater antennas should have an im ped-
ance of
50 ohms at the operating frequency.
When separate receive and transmit antennas
are used, high-Q narrow-band types may
serve to minimize interaction . H owe ve r,
when a single antenna is used with a du-
plexer, it should be a low- Q wide-band typ2.
NEVER TRANSMIT WITHOUT HAV-
ING A TRANSMIT ANTENNA CON-
NECTED TO THE REPEATER.
AC Pow er S upply Voltage Selection
Each repeater is wired for a particular AC
mains voltage between 100 and 234 VA C.
This should be indicated by a label ne ar the
AC jack
on the rear panel. If no label is pre-
sent, or if the AC voltage on the label is differ-
ent from the local AC line, check the wir in g to
the
power transformer inside the rep eater,
and change the connections (and label) if nec-
essary, as
shown on the following page .
Changing the transformer wiring also re-
quires changing the fuse in the power supply
if the voltage is changed from below 117-V
AC to
above 200 VAe, or vice-versa. Use a
Instruction Manu al
5-amp fuse for for 117 VAC or less, or a 3-amp
fuse for 200 VAC or more.
Operation
DC Power Supply Backup
For uninterrupted operation during
power failures, a 12-volt re chargeable type
battery (55-Ah or more recommended) may
be connected to the DC terminal posts on the
rear panel.
While the repeater is operating
from the AC source, a slight charging current
will maintain ba ttery charge. In the even of
AC
power outage, the automatic power con-
trol circuit will
automatically switch the re-
peater to the backup battery, and operation
will not be interrupted.
After prolonged operation from the bat-
tery, it
should be disconnected from the re-
peater and recharged separately before
re-connecting, as the trickle charge is not suf-
ficient for recharging a completely dis-
charged battery. Never reapp ly AC power to
the repeater with a dischar ge d b attery COF-
ne cted, as the DC s ta rtup current can damage
the repeater and
batte ry. While operating
from a battery or DC supply, the repeater
requires approximately 7 amperes at 12 volts
during transmit.
Equipment Loc ation
While the operating temperature range of
the repeater is quite broad, the best location is
still
one in which the air temperature does not
approach the extremes or change rapidly.
M
ake sure to allow for free air circulation
around the heatsink on the rear apron at all
times.
In warm clima tes, the repeater should
not be sealed in a small closed room.
Protect the repeater from wind and rain,
and extremes in temperature or humidity
that may shorten the useful life of the equip-
ment. Try to locate the repeater in an environ-
ment that is also comfortable for service
personnel, if possible.
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