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Crucial safety warning regarding installation and potential damage to tubes.
Overview of the ETO 91ẞ linear power amplifier's capabilities and features.
Detailed technical specifications covering frequency, power, and impedance.
Reference to the diagram illustrating the top view of the amplifier.
Instructions for correctly installing the power transformer within the amplifier.
Guidance on checking tube seating and chimney alignment for cooling.
Details on wiring primary voltage taps and establishing proper amplifier grounding.
Important safety information regarding power cord selection and usage.
Information on power limitations and calculations for 120V operation.
Procedure for connecting the amplifier to a proper RF earth ground.
Instructions for safely reinstalling the amplifier's top cover after service.
Recommended coaxial cables and connectors for RF input and output.
Details on connecting the transmit/receive control cable for proper operation.
Information on using and connecting the ALC for amplifier drive control.
Explanation of the amplifier's front panel controls and their functions.
Step-by-step guide for adjusting the amplifier for optimal performance.
Understanding the role and indication of grid current in amplifier operation.
How ALC works and how to adjust it for smooth amplifier operation.
Procedure for powering on the amplifier and preparing for tuning.
Detailed steps for achieving 1500 watts RF output with preliminary settings.
How the amplifier protects itself from excessive reflected power.
Detailed explanation and adjustment guidance for ALC.
Information on the tubes used, their care, and operational limits.
Explanation of safety interlocks and critical warnings for accessing the interior.
Details on fuse types, ratings, and their importance for protection.
Function of the plate overcurrent relay in protecting the amplifier.
How EBS reduces plate current during idle periods for efficiency.
Description of protection circuits against arcing and mistuning.
Recommended cleaning and maintenance procedures for long-term reliability.
Common causes and checks for the amplifier failing to power up.
Troubleshooting steps for when high voltage is not detected.
Diagnosing issues with multimeter readings while other indicators work.
Resolving problems with the amplifier's turn-on time delay.
Checking T/R control and other factors when the amplifier won't transmit.
Addressing issues causing the red GRID LED to illuminate frequently.
Troubleshooting low output and lack of grid drive indication.
Identifying causes for signal attenuation when switching modes.
Diagnosing abnormal plate current readings during standby or receive.
Causes and solutions for distorted signals and TVI.
Identifying and fixing sources of audio hum in the transmitted signal.
Overview of the RF amplifier stage design and its components.
Description of the amplifier's power supply systems and their components.
Explanation of the control circuitry and its various functions.
Details on the front panel indicators, bargraphs, and displays.
Information about the board responsible for RF power measurement.
Wiring details for the multimeter selector switch.
Comprehensive schematic diagrams for the ETO 91ẞ amplifier.
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General