User's Manual

PINEAPPLE TECHNOLOGY, INC VII. DTXPRO-800VH THEORY OF OPERATION

DTXPRO-800VH OPERATING AND SERVICE MANUAL

THE INFORMATION PROVIDED HEREIN IS PINEAPPLE TECHNOLOGY INCORPORATED PROPRIETARY INFORMATION AND

CANNOT BE COPIED OR DISTRIBUTED WITHOUT PRIOR AUTHORIZATION

VII -- DTXPRO-800VH THEORY OF OPERATION (Continued)

C. PS4KW-50 4 KW POWER SUPPLY ASSEMBLY

The DTXPRO-800VH transmitter is designed with over 4 kW of DC power. To achieve this level,

the power supply in each transmitter rack is made up of two (2) AC2050 power modules mounted

into one (1) main frame assembly, AC2009, which is capable of managing both 2 kW modules.

The power modules are "HOT PLUGGABLE" and can be removed or installed without turning off

the transmitter. Although the transmitter output power would need to be reduced below the level

of power from one PS module. A third power supply module can be purchased for added

redundancy.

Each power supply module has OVER VOLTAGE, OVER CURRENT AND OVER

TEMPERATURE protection as well as a fault signal in the event of a failure.

REFER TO MANUFACTURER'S MANUAL FOR THE RRSI SERIES POWER SUPPLY

PROVIDED WITH THIS DTXPRO-800VH USER MANUAL.

D. ADP1000 PERFORMANCE MONITOR

The ADP1000 Performance Monitor provides the following functions:

1. Provides device current monitoring of all the pallets used in the two (2) PA1KVH-50 power

amplifier assemblies. The current levels can be read directly from the multi-meter on the

front panel. Individual PA's and pallets are selectable on the ADP1000. In normal operation,

a PA FAULT is indicated when the LED goes from green to red. RED indicates that the

current level is below 500 mA and a transistor device may have failed. To read the actual

current, select the appropriate Power Amplifier (i.e.: PA1, PA2) using the push button

switch. Then, using the rotary switch on the ADP1000, rotate through the 5 PA positions to

measure the drain current on each transistor device for the selected power amplifier

module. The multi-meter will read the actual current.

2. A PA INHIBIT switch is provided for failure diagnostic purposes. When activated, this

switch allows the technician to monitor the bias currents for each pallet. These readings

were recorded at the factory and are found on the Transmitter Test Report, DC Test Report

Section. This is the best way to troubleshoot possible transistor problems. When in the PA

INHIBIT mode, the RF PWR OFF LED will change from green to red indicating that the

"SHUTDOWN LINE" is at TTL 0 state and the output power has been reduced to near zero.

3. The PA designations on the ADP1000 are PA5 (inhibited in this transmitter) then PA1 and

PA2, indicating the devices on the left side VHB600A-50 Pallet. PA3 and PA4 indicate the

current through the devices on the right side VHB600A-50 Pallet.