Querying Stations

There are several types of queries one transmit-capable APRS station can make to another. The most common, requesting an updated position report, is automatically issued on a Locate->Station request if YAAC doesn't have recent position information about the requested station. Other common queries supported by YAAC are:

• Query->Station Direct: The list of stations heard directly (not via digipeaters or IGates) by the queried station
• Query->Station Heard: How many messages have been heard by the queried station from a third station
• Query->Station Ping and Query->Station Trace: The path from the queried station to the querying station (using either the ?PING? or ?APRST queries)
• Query->Station Status: What is the remote station's status message?
• Query->Station SW Version: a description of the software being executed on the queried station. Note this query is presently supported only by YAAC, and KJ4ERJ's APRSIS/32 and APRSIS/CE, and will probably be ignored by other stations.

NOTE None of these commands will be available until after you have set up a transmit-capable APRS port in YAAC. You may need to restart YAAC so that the menu bar will notice the new capability and add the extra menu options.

In addition, YAAC can make broadcast queries to search for RF-local stations, either any APRS station, or those performing I-gate or weather station functions. These broadcast queries can only be used when YAAC has a RF connection and will only be transmitted out RF ports.

Also, YAAC can broadcast QRU requests to find out about local resources of various types. Some of the standard QRU groups that are commonly used are:

To find out what QRU codes are in use in your area, send the default query INFO; every QRU server station in range will report the QRU codes they serve and their maximum range.

YAAC can also function as a QRU server, based on the default beacon position. Objects and Items announced by YAAC can be associated with a QRU group, and will be automatically retransmitted when a corresponding in-range QRU request is received.

YAAC can also send and receive lists of tactical callsigns (aliases) in use by RF-local stations and objects; this message interchange is compatible with Xastir and APRS+SA.

The APRS-standard and custom queries that YAAC will respond to are:

Note that the above broadcasts are only permitted on RF, as every station on the planet would be expected to respond if these were sent over the APRS-IS Internet servers.