Broadcast Electronics Marti Electronics ME-40, Manual

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©2011 Broadcast Electronics
microsecond pre-emphasis. If required, an alternate pre ­ emphasis can be selected as
follows.
Procedure to select an alternate pre-emphasis; proceed as follows:
WARNING
DISCONNECT PRIMARY POWER TO THE EXCITER BEFORE PROCEEDING.
WARNING
a. Disconnect the exciter primary power.
b. Remove the exciter top-panel.
c. Refer to the following information and program P5A and P5B as required.
Pre-Emphasis P5A P5B
75 μ s Install Install
50 μ s Remove Install
25 μ s Install Remove
d. Replace the exciter top-panel.
5.11.4 TROUBLESHOOTING.
The troubleshooting philosophy for the AFC/PLL circuit board consists of isolating a problem to a
specific circuit. The problem may be further isolated by referencing the following information and
Figures 5-8 and 5-9 which present troubleshooting information.
WARNING
DISCONNECT PRIMARY POWER FROM THE EXCITER BEFORE REMOVING OR REPLACING ANY
COMPONENTS.
WARNING
CAUTION
INADVERTENT CONTACT BETWEEN ADJACENT COMPONENTS AND CIRCUIT TRACES MAY
DAMAGE THE AFC/PLL CIRCUIT BOARD.
CAUTION
After the problem is isolated and power is totally de-energized, refer to the schematic diagrams
and the theory of operation to assist in problem resolution. The defective circuitry may be repaired
locally or the circuit board may be returned to Marti Electronics for repair or replacement.