[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Handheld Messaging via ECHO



Here is how we can use ECHO to support mobile and handheld global digital
communications:

MOBILE and HT Handheld DATA COMMUNICATIONS VIA ECHO             20 OCT
----------------------------------------------------------------------
                                                                WB4APR

With the 8 Watt 9600 baud downlink from ECHO, the Amateur Satellite
Service will have handheld global message and data capability.  Using the
Kenwood TH-D7 APRS HT or the TM-D700, mobile and handheld front panel
messaging, bulletins and brief email will be a reality using only the
stock rubber duck or typical mobile whip antenna. IE, Ham Radio's own
Satellite Phone!

Here are the digital 9600 baud capabilities of these radios in stand-
alone mode when used via ECHO:

FRONT PANEL DISPLAY OF SATELLITE INFO:
  - Displays Satellite Status packet (20 characters)
  - Displays Satellite Bulletins (up to 45 characters each)
  - Displays distance and direction to ECHO (*)
  - Displays direction of movement of ECHO (*)

FRONT PANEL DISPLAY OF OTHER USER STATION INFO:
  - Displays 20 character station status
  - Displays Bulletins or messages from other stations
  - Displays distance and direction to other user
  - Displays location and grid square of other station
  - Displays type of station (MObile, HT, Fixed, Moving, etc)
  - Displays station ICON (one of hundreds)
  - Displays Direction and Speed of other mobiles
  - Displays Antenna height, Gain, direction and power of other stations
  - Displays Station location on GPS map (If GPS attached)

FRONT PANEL MESSAGING CAPABILITIES:
  - Send and receive text messages up to 45 characters (on the HT)
  - Send and receive text messages up to 64 characters (on the mobile)
  - Receive DX spots or any other tabular data (10 lines max)
  - Send Email for delivery via the global APRS system into the internet

Of course, these are all the normal APRS functions of these radios
used terrestrially on the continental wide  APRS frequencies.  But
to use these radios via satellite during an ECHO pass, there are only
a few front panel MENU items that must be changed:

To RECEIVE (monitor downlink):

   1) Simply tune the radio to ECHO's downlink frequency.
   2) and change the baudrate setting to 9600 baud.

To TRANSMIT VIA ECHO:

   3) Tune TX band to ECHO's uplink frequency
   4) Set TNC to operate crossband and to ignore DCD

SATELLITE CONFIGURATION DETAILS:  The only considerations for the
configuration of ECHO to support this tremendous global handheld
digital satellite capability are to configure ECHO for UI packet
digipeating as follows:

   - Enable UI digipeating at 9600 baud
   - Enable UI digipeating aliases of RELAY and WIDE
   - Optionally program for 20 character ECHO status packets
   - Optionally program for 45 to 64 character BULLETIN formats

I can provide the detail formats for the STATUS and BULLETIN formats
to be compatible with the receipt and disply capabilities of the
radios and assist the ECHO software engineers to optimize details for this
great potential application.

de WB4APR, Bob




----
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org



AMSAT Top AMSAT Home