Doing some additional reading on this I think it's worth mentioning that this may be confusing to APRS and Yaesu users due to the use of angle bracket.
Using an example APRS packet taken from aprs.fi raw feed for the digipeater being used here.
Code:
2023-11-22 08:35:36 MST: AC0XW-1>APDW16,TCPIP*,qAC,T2SJC:!3949.46N110503.55W#Westy Fill-in Digi and IGate, https://AC0XW.TechSavage.net
In a parsed APRS packet the source or destination station is left of the bracket. So in this case AC0XW was the source station. To the right of the bracket is the parsed information that packet had.
But what Yaesu is displaying seems to be an internal status and call sign of heard station.
If anyone's interested the packet was parsed as follows.
The APDW16 is software and version number. APDW16 means the station is using Direwolf (APDW) version 1.6 (16).
Dire Wolf is a software "soundcard" AX.25 packet modem/TNC and APRS encoder/decoder. It can be used stand-alone to observe APRS traffic, as a tracker, digipeater, APRStt gateway, or Inter...
github.com
Next is TCPIP*, which is a third party indicator for a packet received over APRS-IS. When doing APRS over the air this field will be something else.
The next field has qAC, which is part of the q-algorithm for packet routing. This indicates the packet came from a verified source, which is the call sign indicated after it.
That is T2SJC, which is a server on the APRS-IS network, specifically a tier 2 server used on a rotating basis. SJC is run by a volunteer most likely.
This is how all iGates are going to look on APRS. Stations heard or direct RF will be different.
After that colon is the GPS location for AC0XW, 3949.46N110503.55W
And the end is a free text status message.
So a regular station packet.
Code:
2023-11-22 13:40:29 MST: KE0VH-2>T1TQTR,WY7HR-1,WIDE1*,WIDE2-1,qAO,WB7GR-10:`oTpr5lk/`"Bu}447.400MHz T103 -500 SkyHubLink.com, TEXT 4 FREQ 303-704-329_%
In this case the source was KE0VH-2.
T1TQTR means the station is using MIC-E encoding. You can parse it but those 6 digits contain a lot of data.
T1TQTR is 0x54 0x31 0x54 0x51 0x54 0x52
MIC-E uses the least significant byte of digits to make a latitude, so 414142 means 41° 41.42'
The most significant byte is parsed bit-wise but the APRS spec for MIC-E tells you by character what it means.
So:
T in digit one means message is 1
1 in digit two means message 0
T in digit three means message is 1
Q in digit four tells you N/S is north
T in digit give is longtitude offset and is +100°
R in digit six tells you W/S and is west
So we know this station is status 101 and that's message two (M2) and "In-Service" N41° 41.42' and W by at least 100°
To know exact longitude you have to decode the information field, which is the 9 digits [`oTpr5lk/] between the brackets.
[`oTpr5lk/] is [0x60 0x6f 0x54 0x70 0x72 0x35 0x6c 0x6b 0x2f] or [096 111 084 112 114 053 108 107 047]
First digit is data type and the tick (') means current GPS data
Second digit (o) is decimal 111°
Third digit (T) is 84 minutes
Fourth digit p is 112 seconds
Fifth, sixth and seventh are speed and course, (r5l) and pretty convoluted but it's 34 knots or 39 MPH. I'd have to work harder at getting the rest.
Eighth and ninth digits are symbol, (k/) is truck
So from those two fields we know MIC-E encoded "In-Service N41° 41.42' and W111° 84.122' Truck" at least.