Bird Technologies 8640B Series - Manual (Page 35)

Bird 8640 Series Moduload RF Load Resistor
24
3. Use a
3
⁄
16
hex socket wrench to back the cap screws [6]
approximately
1
⁄
2
inch.
4. Pull the water chamber assembly out. It may be necessary to rock
the chamber gently while pulling.
5. If the resistor [1] is intact it may be pulled straight out of the load
housing and is ready for replacement. The outer flow tube is
captive and will not come out of the housing at this stage.
The ground cap assembly [10] and the inner flow tube [9] should come
out with the water chamber assembly. To remove the ground cap
assembly [10], hold the resistor sleeve [7] on the flow tube and pull
out the assembly. This includes the cushioning O-Ring [8] which fits
loosely below the stop sleeve; do not lose it.
The resistor sleeve [7] has a small escape hole at the side and an
access counter bore leading to it. If the sleeve is removed, be sure this
counterbore faces the O-Ring and the resistor [1] during reassembly.
This is essential for internal water venting. The base of the inner flow
tube has water outlet holes and a small shoulder. At reassembly,
these must fit into mating recesses in the input fitting.
Inspection
y Carefully check the resistor [1] for fractures.
NOTE: Even in the event of resistor failure the resistor substrate
will usually remain intact.
y Check the inside of the load housing for damage to the internal
parts. If no damage has been found proceed to “Resistor
Replacement”. However, if the resistor is broken, other internal
parts are damaged, or if the parts do not fit together properly,
proceed to “Fractured Resistor”.
Fractured Resistor
1. Turn the load on end with the RF input connector up to allow any
loose pieces of the resistor to fall out of the housing.
2. Use a 3
⁄
16
hex socket wrench to remove the cap screws [16].
3. Remove the outer conductor assembly [12].
4. Pull out the center conductor assembly [11]. Carefully remove any
remaining pieces of the resistor. Normally the outer flow tube will
remain with the load housing. If it comes out, return it after
inspection and cleaning.
5. Check the inside of the load housing for damage.