Keep in mind that the quoted values are "when a packet signal is present", not just open squelch noise.
Also, a high RXAMP is as bad or worse than a low on.
I have tried 2 methods for setting RX amp:
1. Using a second radio to transmit packets (close by), I will set RXAMP when the MONITOR values are between 75 and 90.
? ? This is because of how strong the signal is.
2. When using a Data Jack, I use a soundcard TNC (like Direwolf) to a potentiometer and feed the TT4 a signal (Vpp) matching the port specification.
? ?In my Yaesu radios, that is 300 mVpp fro 1200baud and 500 mVpp fro the 9600 baud pin.
? ?Using that signal, I set the RXAMP for a monitor value of 75 - 80.
These methods have worked well for me.
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Robert Giuliano
KB8RCO
