Re: iGATE Functioning?


James Ewen
 

Don,

Probably the most important part of this is to learn the various parts of an AX.25 packet.

There's basically the source, destination, path, and payload sections of a packet. Once you can find those parts, then you can start to decode all the information in the payload based on the APRS specifications.

KD4APP-5>APWW11,TCPIP*,qAC,T2KA:<IGATE,MSG_CNT=10,LOC_CNT=0,DIR_CNT=0,RF_CNT=0,DX=7*N4NE-2(45mi@196<0xb0>)

Source    :  KD4APP-5

Destination : APWW11

Path     :  TCPIP*,qAC,T2KA

Payload : <IGATE,MSG_CNT=10,LOC_CNT=0,DIR_CNT=0,RF_CNT=0,DX=7*N4NE-2(45mi@196<0xb0>)

So, it's easy to see that the packet came from your station, aimed at APWW11, and it travelled via TCPIP*,qAC,T2KA

Perhaps Lynn can offer more information about the payload. 

I'm not sure what the msg_cnt is counting... can't find a reference to it in the wiki.

 If you send yourself a ?IGATE you'll see the count of local, direct, and total unique stations received "recently" (30 minutes) on an RF port. I just did that, and here's what your station told me.

14:17:50> ?igate
14:17:51< IGate[1/2] MSG_CNT=20 LOC_CNT=3 RF_CNT=3
        < IGate[2/2] TT4-NEW[KISS] Bi-Directional DX=10*N4NE-2(45mi@196°)

If you send a ?APRSL you'll see the stations that APRSISCE/32 considers "recently" "local" for the purposes of gating messages from the -IS to RF if addressed to one of those.

14:18:07> ?aprsl
14:18:07< Locals:AB4CZ-1(1) KD4UYP-10(1) W4DKZ-9(1)

  ?APRSD shows a list of the direct (no hops used) stations.

14:18:21> ?aprsd
14:18:22< Nothing Heard Direct

 ?APRSH * shows the list of all stations along with their used hop counts in ().  

14:18:37> ?aprsh *
14:18:37< Heard:AB4CZ-1(1) KD4UYP-10(1) W4DKZ-9(1)

RF Ports now track the most distant, directly heard (no path components used), position beacon per clock hour and report it as DX in <IGATE updates as well as in ?IGATE and ?APRSS query responses. You'll also see the DX along with timestamp for the past 8 hours per port if you double-click the "APRS OK" pane.

In all cases, the format of the information is DX=n*station(Dmi@B° (e.g. "DX=1*WX4MLB-3(8mi@2°)") where n=# of direct packets, Dmi=distance in miles, B°=bearing from receiver (aprs.fi's raw packets doesn't show the ° properly).

I also haven't been able to figure out where one might be able to enable/disable this i-gate activity report yet either.


James
VE6SRV


On Wed, Aug 19, 2020 at 12:49 PM Don Woodward <dbwoodw@...> wrote:
Thanks for the info - I'll study the packet info in the link you sent.

73's

Don W.
KD4APP


From: APRSISCE@groups.io <APRSISCE@groups.io> on behalf of James Ewen via groups.io <ve6srv=gmail.com@groups.io>
Sent: Tuesday, August 18, 2020 6:41 PM
To: APRSISCE@groups.io <APRSISCE@groups.io>
Subject: Re: [APRSISCE] iGATE Functioning?
 
Oops, sent too soon.

Basic understanding of the construction of APRS packets is useful...

The APRS101.pdf will help you with this. http://www.aprs.org/doc/APRS101.PDF

2020-08-18 17:17:00 EDT: KD4APP-5>APWW11,TCPIP*,qAC,T2KA:<IGATE,MSG_CNT=10,LOC_CNT=0,DIR_CNT=0,RF_CNT=0,DX=7*N4NE-2(45mi@196<0xb0>)  

Timestamp the APRS-IS heard the packet

2020-08-18 17:17:00 EDT:   

Source callsign (station sending the packet) 


Destination (TOCALL) used by APRS to identify the source station software in this case, APRSISCE/32 

  APWW11, 

Handled by a network connection

  TCPIP*,  
 
q construct (http://www.aprs-is.net/q.aspx) sent to the APRS-IS directly by a verified connection

  qAC,  

APRS-IS server that handled the packet.

  T2KA: 

Actual packet contents finally! This is determined by Lynn's software. I'm going way out on a limb here expanding the term...

 <IGATE,MSG_CNT=10,LOC_CNT=0,DIR_CNT=0,RF_CNT=0,DX=7*N4NE-2(45mi@196<0xb0>)  

IGATE is reporting information.

  <IGATE, 

Message Count

MSG_CNT=10, 

Location Count

  LOC_CNT=0 

Heard Direct Count 

  DIR_CNT=0 

Heard via RF Count 

RF_CNT=0  

Furthest station heard

  DX=7*N4NE-2(45mi@196<0xb0>) 

DX = shortened term for distance commonly used by amateur radio operators.
7* (number of time heard?)
N4NE-2 (callsign of the station heard, including SSID.
45mi distance to station in miles.
196° bearing to station.

The <0xb0> is the degree symbol that is being shown as a non-printable ascii hex code.

So no, your station is not sending packets to N4NEQ-2 via RF (at least not as indicated by this packet.)


James
VE6SRV


On Tue, Aug 18, 2020 at 4:31 PM James Ewen <ve6srv@...> wrote:
Basic understanding of the construction of APRS packets is useful...

The APRS101.pdf will help you with this. http://www.aprs.org/doc/APRS101.PDF

2020-08-18 17:17:00 EDT: KD4APP-5>APWW11,TCPIP*,qAC,T2KA:<IGATE,MSG_CNT=10,LOC_CNT=0,DIR_CNT=0,RF_CNT=0,DX=7*N4NE-2(45mi@196<0xb0>)  

Timestamp the APRS-IS heard the packet

2020-08-18 17:17:00 EDT:   

Source callsign (station sending the packet) 


Destination (TOCALL) used by APRS to identify the source station software in this case, APRSISCE/32 

  APWW11, 

Handled by a network connection

  TCPIP*,  
 
q construct (http://www.aprs-is.net/q.aspx) sent to the APRS-IS directly by a verified connection

  qAC,  

APRS-IS server that handled the packet.


James
VE6SRV


On Tue, Aug 18, 2020 at 3:57 PM Don Woodward <dbwoodw@...> wrote:
Does this mean my iGATE has sent packets via RF to N4NEQ-2 ?

2020-08-18 17:17:00 EDT: KD4APP-5>APWW11,TCPIP*,qAC,T2KA:<IGATE,MSG_CNT=10,LOC_CNT=0,DIR_CNT=0,RF_CNT=0,DX=7*N4NE-2(45mi@196<0xb0>)

TIA and 73's

Don W.
KD4APP

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