User's Manual

PINEAPPLE TECHNOLOGY, INC.
UTX3K ULTRA Operating and Service Manual
V -- THEORY OF OPERATION
V
--- THEORY OF OPERATION (Page 1 of 5)
A
. INTRODUCTION
The UTX3K ULTRA transmitter was designed to meet or exceed all FCC applicable specifications for
TV broadcast equipment. Special attention was given to the selection of sub-assemblies and components
to achieve maximum reliability and minimum down time. The construction of the UTX3K ULTRA is
BASIC and MODULAR with most components field replaceable. Special emphasis was placed on
"KEEPING IT SIMPLE" and returning to more traditional transmitter layouts and instrumentation.
This transmitter was designed for Analog (NTSC) transmission with provisions and options available to
convert to Digital Service at a later date if necessary.
Refer to the UTX3K ULTRA block diagram in for an overview of the transmitter architecture. This will
give the technician basic information needed to understand the operation of the transmitter and the function
of each subassembly.
SEE SECTION Vl.A FOR PARTS LIST AND BLOCK DIAGRAM.
B. ACDIS2 AC & DC DISTRIBUTION
The ACDIS2 is the primary AC power inlet module. The UTX3K ULTRA transmitter was designed to accept
220 to 240 VAC Single Phase (Standard) using a four (4) wire connection (208 3 Ø Optional). The four wires are:
Standard
Optional
--- 2 wires for 220 -240 VAC Single Phase --- 3 wires for 208 - 240 VAC 3 Phase
--- 1 wire for neutral connection --- 1 wire for neutral connection
--- 1 wire for safety ground connection --- 1 wire for safety ground connection
CAUTION:
Connection to the AC Primary source must be made using all four wires listed above. Follow
the wiring instruction given in TRANSMITTER INSTALLATION Section lll.3. If not followed, severe damage to
the transmitter and, or, electrical shock could result.
The ACDIS2 performs the following functions:
1. Provides a primary AC power breaker point to shutdown the transmitter
2.
Provides 220 (208 3Ø) VAC power to each of the three 2 KW DC power supplies with individual breaker
points for added safety.
3. Provides 110 VAC circuits for Modulator, ADP500, ABS (as necessary) and AUX Power where
needed.
4.
A
nalog metering is provided to monitor the Power Supply voltage and current being applied to the
RF Amplifier states.
5. Power supply current sharing test points are provided for checking current sharing between
power supply modules.
SEE SECTION VI.B FOR SCHEMATIC AND PARTS LIS
T
C. AC2008 2KW POWER SUPPLY MODULE
The UTX3K ULTRA transmitter is designed with over 6 KW of DC power. To achieve this level, the power supply
in each transmitter rack is made up of three (3) TWRI6004 (PTI Part # AC2008) power modules mounted into
one (1) main frame assembly (PTI Part # AC2009) which are capable of managing three (3)
2 KW modules each.
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