Data Sheet Chapter 5

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LX Series Power Amplifier Assembly Chapter 5, Detailed Alignment Procedures

LX Series, Rev. 0 5-1

Chapter 5

Detailed Alignment Procedures

This Power Amplifier Assembly along with

the translator was aligned at the factory

and should not require additional

adjustments to achieve normal operation.

This translator takes the baseband audio

and video inputs or, if the (Optional) 4.5-

MHz composite input kit is purchased,

either a single composite video + 4.5-

MHz input or separate baseband video

and audio inputs, and converts them to

the desired UHF On Channel RF Output at

the systems output power level.

The power amplifier assembly of the

Innovator LX Series translator is of a

Modular design and when a Module fails

that module needs to be changed out

with a replacement module. The failed

module can then be sent back to Axcera

for repair. Contact Axcera Customer

Service Department at 724-873-8100 or

fax to 724-873-8105, before sending in

any module.

5.1 Module Replacement

Module replacement on the LX Series

products is a relatively simple process.

The power supply and power amplifier

modules, plug into a blind mating

connector located on the chassis. To

replace a module, refer to the following

procedure.

Loosen the two grip lock connectors,

located on the front panel, at the top

and bottom of the module,

counterclockwise until the module

releases. There are two cables

connected to the rear of the Power

Amplifier Module. These two cables must

first be removed before the PA module

will slide out.

After removal of the failed module, slide

the replacement module in place and

make certain it connects to the blind

mate connector. Replace the two cables

on the rear of the chassis assembly. If

the replacement module does not slide

in easily, verify it is properly aligned in

the nylon tracks, located on both the top

and bottom of the module.

Note: Each Module has an assigned slot

and will not fit properly in the incorrect

slot. Do not try to place a Module in the

wrong slot as this may damage the slot

or the blind mate connectors.

5.1.1 Initial Test Set Up

Check that the RF output at the coupler

is terminated into a dummy load of at

least the rated output of the system.

While performing the alignment, refer to

the Test Data Sheet for the translator

and compare the final readings from the

factory with the readings on each of the

modules. The readings should be very

similar. If a reading is way off, the

problem is likely to be in that module.

Switch On the main AC for the system.

5.2 Innovator LX Series

Exciter/Amplifier Chassis Assembly

This translator operates using the

baseband audio and video inputs or, if

the (optional) 4.5-MHz composite input

kit is purchased, either a single

composite video + 4.5-MHz input or

separate baseband video and audio

inputs.

On the LCD Display, located on the

Controller/Power Supply Module, in

Translator Set-Up, push the button to

switch the translator to Operate. The

check of and the setup of the Audio and

Video input levels are completed using

the LCD Display and the front panel

adjustments on the Modulator assembly.

The level of the RF output includes

adjustments of the drive level to the

Power Amplifier and the adjustment of

Summary of content (7 pages)

PAGE 1
LX Series Power Amplifier Assembly Chapter 5, Detailed Alignment Procedures Chapter 5 Detailed Alignment Procedures This Power Amplifier Assembly along with the translator was aligned at the factory and should not require additional adjustments to achieve normal operation. on the rear of the chassis assembly. If the replacement module does not slide in easily, verify it is properly aligned in the nylon tracks, located on both the top and bottom of the module.
PAGE 2
LX Series Power Amplifier Assembly Chapter 5, Detailed Alignment Procedures the linearity and phase predistortion to compensate for any nonlinear response of the Power Amplifier. The adjustments are located on the front panel of the IF Processor module. ALTERNATE IF (DS7) – Red Indicates that an external 45.75 MHz IF is not present to the modulator. 10 MHz PRESENT (DS2) – Red Indicates that an external 10 MHz reference in not present to the modulator.
PAGE 3
LX Series Power Amplifier Assembly Chapter 5, Detailed Alignment Procedures located on the front panel of the modulator, as necessary, for the ±15kHz deviation. DS1, AGC Cutback, just starts to flash. Return the output power of the translator to 100%. IF Processor Module Assembly 5.2.1 Linearity Correction Adjustment Verify that all red LEDs located on the IF Processor front panel are extinguished.
PAGE 4
LX Series Power Amplifier Assembly Chapter 5, Detailed Alignment Procedures Figure 5-1. Typical Red Field Spectrum 5.2.2 Frequency Response Delay Equalization Adjustment Note: The frequency response adjustment is done at IF, so the frequency cut-in points will be reversed at the UHF frequencies. The procedure for performing a frequency response delay equalization adjustment for the translator is described in the following steps: 5.2.
PAGE 5
LX Series Power Amplifier Assembly Chapter 5, Detailed Alignment Procedures Example is for 1000 Watt translator. the System Errors Menu. Turn the power adjust pot slightly CCW and the fault should be clearable on the System Error Menu. Turn the pot CW until the Fault appears. The reflected output power is now calibrated. • Sync + black 0 IRE setup/wattmeter=595 watts • Sync + black 7.
PAGE 6
LX Series Power Amplifier Assembly Chapter 5, Detailed Alignment Procedures adjustments. The Trap Filter is comprised of four trap sections connected to the main transmission line. effect the Notch Depth in addition to the Center Frequency. The variable that is being adjusted with this procedure is the length of the Center Conductor inside the Trap Filter. The gap between the Trap and the Main Line should not be changed.
PAGE 7
LX Series Power Amplifier Assembly Chapter 5, Detailed Alignment Procedures Output Trap Filter for at least one hour to allow for warm-up drift. This completes the detailed alignment procedures for the LX Series translator. The Translator is ready for normal operation. If a problem occurred during the alignment, help can be found by calling Axcera field support at 724-873-8100. LX Series, Rev.