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1500 watts PEP output from a Kenwood TL-922 amplifier requires careful attention to parasitic suppression and component selection to ensure stability and longevity. This resource critically examines common modifications, often based on anecdotal evidence rather than sound engineering principles, that can degrade performance or introduce new issues. It highlights how replacing aged components often gets misattributed to the efficacy of unnecessary modifications, leading to widespread misinformation within the amateur radio community regarding amplifier stability. The article details specific, effective modifications for the TL-922, such as shortening anode-to-chassis and anode-to-grid paths to improve VHF stability and efficiency. It addresses issues like incorrect capacitor types in the tank circuit, inadequate grid grounding, and poor RF sheet metal design, providing practical solutions like adding direct ground connections for the plate tune variable capacitor. The author also discusses proper parasitic suppressor design, emphasizing the importance of lead length and component selection for optimal performance and harmonic suppression, contrasting these with less effective or detrimental 'magical suppression kits'.

Demonstrates an **Arduino-based** solution for the Icom IC-7300 transceiver, specifically addressing the operational inconvenience of switching between a CW paddle and a straight key. The project leverages the IC-7300's **CI-V bus** (Computer Interface 5) to provide instant keyer type selection and two preset power levels, bypassing the rig's menu system which otherwise requires eight button presses. This implementation utilizes the 3.5mm CI-V connector, leaving the USB port free for CAT control and the internal soundcard, a critical design choice for integrated station setups. The system's utility is particularly evident for CW operators who frequently alternate between keying methods during contesting or general operating. The article details the hardware setup, including an Arduino Nano, a 3.5mm jack for CI-V, and pushbuttons for control. An update in 2023 expanded the project to incorporate an 8-button Nintendo controller, enhancing user interface flexibility and demonstrating the adaptability of the initial design for further customization and feature integration.