Continental Electronics 816R - General Information; Introduction; Functional Description; Physical Description

816R FM TRANSMITTER
TRAINING MANUAL
I. GENERAL INFORMATION
A. INTRODUCTION
The 816R transmitters operate in the FM broadcast
range (88-108 MHz) with maximum power outputs
of 21.5 kW (816R-2C), 25 kW (816R-3C), 27.5
kW (816R-4C), 30 kW (816R-6C), and 35 kW
(816R-5C). Reduced power is available by tap
changes of the plate and screen transformer to meet
customer requirements. When the exciter receives
input from the optional stereo generator and SCA
generator, the transmitter provides continuous
monaural, stereophonic, and SCA (subsidiary
communication authorization) frequency-modulated
programs.
B. FUNCTIONAL DESCRIPTION
The transmitter consists of an exciter, a solid-state
driver, and a power amplifier. The output of the
exciter is applied to the driver. The driver consists
of a 700-watt module. The input to the driver is
amplified to approximately 500 watts and applied to
the power amplifier that contains one 4CX15000A
in power levels of 27.5mkW and lower. The 30
and 35 kW transmitters use the YC130 tube. All
are operated class C. The output of the power
amplifier is applied to a 50-ohm unbalanced load.
Power control circuits monitor the RF output power
level. When a change in output power is detected,
these circuits change the plate voltage to
compensate. Other control circuits within the
transmitter monitor reflected power, forward
power, operating voltage, air pressure and exhaust
air temperature within the power amplifier section.
They protect the transmitter by removing power
when excessive currents, VSWR, loss of air
pressure, or excessive air exhaust temperature
occur.
C. PHYSICAL DESCRIPTION
The transmitter is housed in a unistrut cabinet that
contains all transmitter components. Refer to
drawing on inside back cover. The transmitter
contains three sections. The section on the left
contains the power amplifier. The center section
houses the control panel, exciter, driver circuits.
and control circuits. The section on the right
contains the power supplies, the circuit breakers,
and fuse panel. (The 35 kw transmitter's High
Voltage Power Supply is external and contains the
High Voltage Transformer, Rectifiers, and Transient
Suppression Circuits.)
II. OPERATION
A. GENERAL
The transmitter may be operated from the local
control panel or by remote control. Once the
transmitter has been installed and properly tuned, it
is only necessary to monitor meter indications and to
make periodic minor tuning and loading
adjustments. Instructions for the 802B exciter are
found in the Exciter Instruction Manual.
B. INITIAL TURN-ON PROCEDURE
1. Ensure transmitter has been assembled and
connected.
2. Remove access panel of Card Cage Assembly
for access to the control circuit cards. Check the
circuit cards for proper installation.
3. Install Card Cage access panel and ensure all
doors and panels are properly closed or
installed.
4. Ensure all transmitter circuit breakers on A6
panel are OFF.
5. Connect primary power to transmitter and set
AC LINE circuit breaker on AC Metering Panel
to ON.
6. Set the 28 VDC POWER SUPPLY and
BLOWERS circuit breakers to ON. Check the
PHASE LOSS indicator on the Al Control
Panel. If this indicator is not on, set AC LINE
circuit breaker on AC Metering Panel to OFF.
Remove the right front bay access panel. Locate
A8K5 (the phase loss/phase rotation monitor)
and turn its control to minimum (full
counterclockwise). Install the access panel and
restore primary power. If the PHASE LOSS
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