Bird Technologies 8072A Series - Manual (Page 12)

Cleaning 1. Gently remove loose dirt and grime using a soft
clean cloth dampened detergent and water. Do
not use paint thinner or other solvents that may
cause damage to the finish.
2. RF Connectors - Clean RF connectors with a cot-
ton swab dampened with alcohol, or any accept-
able dry cleaning solvent.
+
NOTE: Keep the RF connectors covered when
not in use. This will prevent dust and dirt from
accumulating in the connectors.
Measure dc
Resistance of
Load
Items required:
Multimeter or ohmmeter with accuracy of ±1% @ 50 ohms.
Temperature of the load @ 20° to 25° C (68° to 77° F).
VSWR and RF Impedance are the true benchmark of a qual-
ity dummy load. Checking the dc resistance is simply used to
measure a change in the condition of the resistor over time.
The tracking of the dc resistance must start before the resis-
tor is first put into service. Perform the following steps and
record the value for future comparison. Check and record the
resistance of the load periodically according to use.
WARNING
Never attempt to connect or disconnect the equipment
from a transmission line while RF power is applied.
Leaking RF energy is a potential health hazard.
1. Disconnect RF Coaxial Line.
2. Connect multimeter with a short length of low re-
sistance cable equipped with a Male N (or appli-
cable) connector, or connect multimeter test leads
across center and outer conductor of the load re-
sistor.
3. Record the value of the resistance before the load
is put into service. Compare subsequent values
with the latest reading. If the values vary more
than 2 ohms this could be an indication of a fail-
ing resistive element.
Models 8072A-1 & 8072A-2 Termaline RF Coaxial Load Resistor
4