Broadcast Electronics FM-5T, User Manual

Page: 74 / 191

5-13
WARNING: DISCONNECT POWER PRIOR TO SERVICING
5-96.
TRANSMITTER POWER LEVEL CHANGE.
WARNING
WARNING
NEVER OPEN THE EQUIPMENT UNLESS ALL TRANS
MITTER PRIMARY POWER IS DISCONNECTED. USE
THE GROUNDING STICK PROVIDED TO ENSURE ALL
COMPONENTS AND ALL SURROUNDING COMPO
NENTS ARE DISCHARGED BEFORE ATTEMPTING
MAINTENANCE ON ANY AREA WITHIN THE TRANS
MITTER.
5-97. Each transmitter is programmed, operated, and tested at a specific power level at the fac
tory prior to shipment. If at a future date the transmitter is to be operated at a power level
other than the original factory programmed level, the following transmitter parameters
must be checked and adjusted if required to assure proper transmitter operation. If prob
lems occur during initial operation, contact the Broadcast Electronics Customer Service
Department for additional service procedures.
A. Refer to SECTION III, OPERATION and reset the APC operating reference.
B. Energize the transmitter primary ac power and operate the transmitter. Adjust
the input tuning control for a minimum exciter reflected power indication on the
multimeter (for high reflected power conditions, use the multimeter grid current
function and maximum grid current information for indications of correct tuning
operations).
C. Refer to CONTROLLER SECTION II, MAINTENANCE and perform the
FORWARD POWER CALIBRATION and REFLECTED POWER CALIBRATION
adjustment procedures.
5-98.
TRANSMITTER FREQUENCY CHANGE PROCEDURE.
CAUTION
CAUTION
CONSULT THE FACTORY BEFORE ATTEMPTING TO
CHANGE THE TRANSMITTER OPERATING FRE
QUENCY.
5-99.
GENERAL.
The following text presents an overall procedure to change the transmitter op
erating frequency. The procedure specifies operational adjustment procedures located
throughout this publication and FM-250C publication 597-1004. To change the transmit
ter operating frequency, proceed as follows.
5-100. Procedure. To change the transmitter operating frequency, proceed as follows:
WARNING
WARNING
NEVER OPEN THE EQUIPMENT UNLESS ALL TRANS
MITTER PRIMARY POWER IS DISCONNECTED. USE
THE GROUNDING STICK PROVIDED TO ENSURE ALL
COMPONENTS AND ALL SURROUNDING COMPO
NENTS ARE DISCHARGED BEFORE ATTEMPTING
MAINTENANCE ON ANY AREA WITHIN THE TRANS
MITTER.
WARNING
WARNING
DISCONNECT ALL TRANSMITTER PRIMARY POWER
BEFORE PROCEEDING.
5-101. Disconnect all transmitter primary power. The primary ac power must remain OFF unless
specified by an adjustment procedure.