Interesting point about the relative sensitivity of different transmitters' key inputs.
Anytime I encounter scratchy contacts in switches, pots, or keys and bugs, I reach for DeOxit D5. It has proven highly effective in the several decades I've used it and its predecessors.
On sale now at Full Compass
https://www.fullcompass.com/prod/025520-caig-labs-d5s-6-deoxit-contact-cleaner-5-spray-5-oz
Steve WD8DAS
sbjohnston@aol.com
http://www.wd8das.net/
http://af4k-crystals.com
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