Modify the squelch found in the Midland 13-509 radio for better performance.
1. C89: replace 4.7 uF with 1 uF or 0.33 uF (I think I used 1 uF; 0.33 uF made the squelch action a bit too choppy).
2. C91: replace 4.7 uF with 0.47 uF
3. Add a 1 megohm resistor between base of TR13 & collector of TR14. This adds hysterisis which allows the squelch tail to be shorter without chopping, similar to how the G.E. MVP squelch works. See the image below for help with the resistor placement.
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