I ran a test that Rich suggested. Specifically I used an HP signal
generator to produce test signals of -50dBm to -90dBm. The received RSSI
at the AX5043 is within 1 - 2dB. This suggests that the antenna
connection, matching circuitry and filter are all working. The signal is
getting to the chip as expected.
Tuning the signal up/down does not improve things. So the chip does seem
to be on the right frequency. I also ran the "test freq" function (after
modifying it to work with the AX25 code). It transmits on the receive
frequency, and it seems to be correct within a kHz or so.
So this leaves us, as expected, with some sort of register setup issue.
Given it is worse on 2m than 70cm it is perhaps a bandwidth or frequency
acquisition issue.
73
Chris
--
Chris E. Thompson
chrisethompson(a)gmail.com
g0kla(a)arrl.net