Ramakrishnan VU2JXN on Nostr: This ended in failure. The heat transfer to the heatsink is not happening. As soon as ...
This ended in failure. The heat transfer to the heatsink is not happening. As soon as I increase the bias to ~25mA (the bias point is at 100mA), thermal runaway happens and increases the current and temperature etc.. Got a lot of help from the designer of the PA.
TinySA plots till 800MHz shows there is no self oscillation.
I de-soldered and cleaned the PCB surface today and cleaned the surface. Going to attempt to apply more solder paste and try to get it in place properly again..
Published at
2024-01-10 17:50:16Event JSON
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"content": "This ended in failure. The heat transfer to the heatsink is not happening. As soon as I increase the bias to ~25mA (the bias point is at 100mA), thermal runaway happens and increases the current and temperature etc.. Got a lot of help from the designer of the PA.\n\nTinySA plots till 800MHz shows there is no self oscillation.\n\nI de-soldered and cleaned the PCB surface today and cleaned the surface. Going to attempt to apply more solder paste and try to get it in place properly again..",
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