this is my old aprx conf
it ran fine business but i've moved onto a wx3in1plus now.
i used a first gen pi model b
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mycall KB0WLF-10
myloc lat 3736.88N lon 09131.83W
<aprsis>
passcode CHANGE THIS
server noam.aprs2.net
# filter "f/n0jqx*" # friend filter
filter "m/200" # range filter
# filter "b/n0jqx-9/n0jqx" # budlist
# filter "o/ISS*" # space station
# heartbeat-timeout 1m
</aprsis>
#<logging>
# pidfile /var/run/aprx.pid
# rflog /var/log/aprx/aprx-rf.log
# aprxlog /var/log/aprx/aprx.log
# erlangfile /var/run/aprx.state
#</logging>
<interface>
serial-device /dev/ttyUSB0 9600 8n1 KISS
tx-ok true
telem-to-is true
</interface>
<digipeater>
transmitter $mycall
<source>
source $mycall
</source>
<source>
source APRSIS
relay-type third-party
# viscous-delay 5
# filter "b/n0jqx-9/n0jqx" # budlist
# filter "o/ISS*" # space station
</source>
</digipeater>
<beacon>
# beaconmode both
cycle-size 30m
beacon via WIDE2-2 \
symbol "T&" $myloc comment "PHG5360/KB0WLF piGATE"
</beacon>
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this conf is probably NOT the best/slickest/greatest/streamlined file but i KNOW it ran without error.
digipeater + igate
it showed up as a black diamond with a T (transmitting igate, digigate)
hopefully you can get an idea of what to put where.