6
West Mountain Radio Operating Manual
The RIGrunner provides an accurate and unambiguous display of voltage. There
are three LEDs: red overvoltage, green normal, and yellow undervoltage. The
points at which the LEDs change are set accurately to 11.5 and 15.0 volts. The
selection of these points gives a reliable indication of proper and safe operation
of your power supply, battery or alternator. A green or normal indication is all
you need to look for.
An undervoltage indication, shown by the yellow LED, is less than 11.5 volts.
This should be safe for your radio, but may cause improper operation. Low
voltage on a modern radio can cause a loss of phase lock and a frequency
error. This is a definite indication of a problem with the power source; a bad
connection, an unregulated power supply, a bad alternator or dying battery. It
is normal with most cars to have less than 11.5 volts when cranking the starter
motor.
A normal indication with the green LED illustrates, everything is good and you
are between 11.5 and 15.0 volts, don’t worry about a thing.
A red overvoltage indication with the red LED is a warning, DISCONNECT OR
TURN OFF YOUR POWER SUPPLY IMMEDIATELY! It is possible to overheat
or damage a radio or other equipment. An overvoltage will sound an audible
alert; no need to watch the LEDs to signal a problem.
When running strictly on a 12 volt battery, an overvoltage condition will not
occur. The RIGrunner’s audible alert can be reconfigured for a low battery
warning. By removing the four cover screws and move the P14 jumper to the
“LO” position. Remember to move it back to “HI” when changing back operation
from power supply or alternator.
Note: Due to the characteristics of the comparator chip it is normal for the
undervoltage LED to glow very dimly with a normal or overvoltage indication.
It is also normal for the LEDs to change intensity while stepping through 10
precision points.
In the event of a bad power source or power connection, the yellow LED may
flash or come on during transmit. If this happens, check the power source
and connections. It is also possible for RF from a transmitter to cause
an electronically regulated power supply to lose regulation and cause an
overvoltage alert during transmit. The RIGrunner is extensively RF bypassed
and should actually cure this problem. If you do have an overvoltage condition
during transmit especially with a VHF high power amp, it is due to inadequate
RF filtering on the DC lead of the amplifier, or poor RF immunity of the power
supply regulator circuit.
