10 000 WATT FM BROADCAST TRANSMITTER
FM10
Page 5-13
01 October 2002
TEMPORARY REPLACEMENT OF IPA
MODULE WITH RF POWER MODULE
5.8
The transmitter can operate, at a reduced
power level, with the IPA module replaced by an
operational RF power module. Replace the IPA
module with an RF power module as follows:
The IPA module contains solid state devices that
may be damaged if they are subjected to excessive
heat or high voltage transients. Every effort must
be taken to ensure circuits are not overdriven and
they are not disconnected from their loads while
turned on.
(a) Press/release the control/monitor panel's RF
OFF switch.
(b) Turn off the exciter.
(c) Set MAIN POWER circuit breaker to OFF
(down). The circuit breaker panel's AC ON lamp
shall turn off.
5.8.1 RF POWER MODULE REMOVAL:
Remove the operational RF power module which
temporarily replaces the IPA module as follows:
(a) Verify requirements of paragraph 5.8 have been
completed and are being met.
(b) Refer to figure MD-1 to verify the reference
designation of the RF power module being
removed to replace the IPA module and to
figure MD-5 as an aid in locating the associated
PWR MDL circuit breaker.
(c) Set PWR MDL circuit breaker, identified in step
(b), to OFF (down).
(d) Gain access to the rear of the RF power
modules by removing the two air filter panels
on the rear of the transmitter (refer to figure
MD-2). Retain all securing hardware.
(e) Identify cables (prefixed by 'W') mating with
the associated RF power module connectors J1
thru J6.
When disconnecting cable mating connectors from
J1 thru J6 or J9 on the rear of the RF power
module to be removed, ensure the mating
connectors at the combiner end or splitter end are
removed also.
(f) Locate the corresponding cables (prefixed by
'W') at the combiner end and disconnect them.
(g) Locate the corresponding cable (prefixed by
'W') at the splitter end and disconnect it.
(h) Disconnect all nine mating connectors from J1
thru J9 on the rear of the RF power module to
be removed.
(i) Remove attaching hardware (hexagon nuts and
washers) from rear retaining studs of RF power
module to be removed.
(j) Carefully withdraw RF power module from the
front of the cabinet.
(k) Locate the PA TUNE switches on the power
module interface PWB (A13). Switch S1-1,
S1-2, S2-1 and S2-2 to the TUNE
position
(away from the NORMAL position) as the
associated PAs are not used when the module is
used as an IPA. (Switch numbers as read on
switch)
(l) Disconnect wire #11 from TB1-13 on the
power module interface PWB (A13) and tyrap
securely to the RF power module's wiring
harness.
NOTE
When the replacement RF power module is no
longer required, ensure wire #11 is reconnected to
TB1-13 and switches reset to
NORMAL
on the power
module interface PWB (A13) before returning the
RF power module to its original location.
5.8.2 IPA MODULE REMOVAL: Remove a
defective IPA module as follows:
(a) Verify requirements of paragraphs 5.8 and
5.8.1 have been completed and are being met.
(b) Disconnect the following mating connectors on
the rear of the IPA module:
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