Engineering Change Order Log A225

This document is an engineering change order (ECO) log for the A225 deflection amplifier, which is used in VR14 and GT40 hardware. It details ten specific engineering changes (A225-00001 through A225-C0010) issued between 1971 and 1973.

The listed modifications address various technical issues, including:

• Component Adjustments: Modifying resistor and capacitor values to resolve issues with gain, signal input, crossover distortion, and settling time/ringing.
• Hardware Improvements: Increasing heat sink sizes for transistors and replacing metal screws with nylon screws to prevent short circuits.
• Design and Documentation: Updating circuit schematics and layout standards.
• Compatibility: Creating a "YB" variation of the A225 amplifier specifically for the GT40 system.

The log provides the specific nature of each problem, the required corrective actions, and details regarding implementation for in-plant production versus field service, including labor time estimates and kit requirements.