Bird Technologies 8327-300 - Manual (Page 19)

Chapter 4
Operating Instructions
There are no operating controls for the Model 8327-300 Attenuator. Read and become
familiar with the following instructions before operating the unit. If your attenuator
is equipped with a thermoswitch, refer to the instructions for connection to the
interlock.
Initial Adjustments Before connection of the attenuator, perform the following steps.
1. Wipe all connectors and insulator surfaces on the transmission line
face with a clean soft cloth.
2. Check the RF input connector. Clean the connector if necessary. Use
a self-drying, non-residue forming contact cleaner on the inaccessible
portions of the connector.
3. Check the input resistance of the attenuator. Refer to the Mainte-
nance chapter.
WARNING
Never attempt to disconnect the equipment from the transmission line while RF power is
being applied. Leaking RF energy is a potential health hazard.
Connection The front or input end of the attenuator is identified by the four inch (102 mm)
diameter die-cast aluminum disc on which the connector is mounted. The rear face
of the unit has OUTPUT stenciled above the connector.
Do not couple the attenuator
backwards to the direction of power flow. Destruction of the output resistor will
result.
1. Connect the attenuator input to the transmitter’s power output. Use
50 ohm coaxial cable.
2. Connect the attenuator output to a suitable load with 50 ohm coaxial
cable (RG-8A/U, RG-9/U, RG-213/U or equivalent) equipped with
connectors which mate with the RF output connector of the attenu-
ator.
3. Follow the transmitter manufacturer’s instructions.
+
Note: If the attenuator is to be operated at both maximum power and frequency
values, use a Male LC connector with a suitable cable (RG-218/U or RG-220/U)
on the input and Male N connector with appropriate cable or load on the output.
These connect to the RF fittings normally supplied.
Before applying any RF power to the attenuator, be certain to check that the vent
plug is in place in the vent hole. Refer to Installation.
Normal Operation
WARNING
Using this load in the upper end of its power dissipation range will cause the housing to
become hot! Care should be exercised in touching it.
WARNING
The vent plug must be used at all times when the unit is in operation or cooling. Failure to
do this could result in damage to the equipment and endanger the operator’s safety. Be
sure to check this plug.
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