DX

Command

DX -- Displays distant APRS stations.

Synopsis

DX [port]

Description

The DX command displays a list of the most distant APRS stations heard by XRPi, along with their positions, distances and headings.

Providing the router's position is defined (see below), APRS position reports heard by the router will be recorded in the DX list, in order of distance.

The sysop may set this up (using the DXFLAGS keyword in XROUTER.CFG) to show only the directly heard stations, or may choose to include those heard via digipeaters. He may also specify a minimum distance for table inclusion.

If included, digipeated stations are clearly identifiable by an entry in the "Via" field, which is blank for directly heard stations.

Options

When no argument is used, stations received on all ports are displayed.

If an optional port number is supplied, only the stations received on that port will be shown

Examples

DX      - Display all DX stations
DX 13   - Display DX from port 13 only.

Typical response to "DX" command..

G8PZT:KIDDER} Dx list:
Prt Callsn Dist Dir  Date  Time Frm Position           Via
9   GB7GH  62Km 170  22/08 10:59 72 5151.20N 00205.80W
4   G6GUH  21Km 325  22/08 05:41  1 5233.38N 00225.80W
1   G3KFD  13Km  36  21/08 17:38  5 5229.65N 00208.28W
(End of list)

Fields are as follows:

Prt      - Radio port number
Dist     - Distance in Kilometers from XRPi's position
Dir      - Heading in degrees from XRPi's position
Date     - Date & time of last reception
Frm      - No. of frames seen from this callsign
Position - Latitude & longitude of station in APRS format
Via      - Digipeater callsign (blank if heard direct)

Files

The DXFLAGS=n directive is used in XROUTER.CFG to control the DX list. The flags are made up as follows:

	1 - Record digipeated stations (defaults off).
	2 - Enable logging of DX exceeding specified distance.
	4 - Log frame contents of qualifying DX

If logging is enabled Bits 3 - 14 specify the minimum distance which will be logged, from 4Km to 32764Km in 8Km steps, e.g. DXFLAGS=502 enables DX logging, with a threshold of 500Km. If logging is not enabled, bits 3-14 are ignored.

If DX logging is enabled, any received APRS positions which exceed the threshold distance are logged to LOG\DXLOG.TXT.

XRPi's position is defined in XROUTER.CFG, either by using LOCATOR (which gives a coarse position), or by including an APRS position string in the IDTEXT, for example:

IDTEXT !5224.00N/00215.00W Kidderminster Router (KIDDER) ***

Caveats

If XRPi's position has not been defined, no DX information will be available

Availability

All users.

See also

AMSG(1) -- APRS Messaging Shell