Operating a MEPT Using an Android Device
========================================

(C) Murray Greenman ZL1BPU Nov 2014

Scenario
--------

You have a WAV file on your old tablet (old phone or a $50 mini PC), and you run a simple
control program which causes the device to play an audio file every 10 minutes (or whenever
you decide). You will need a PTT controller such as:

http://www.qsl.net/zl1bpu/SOFT/VOX%20PTT%205.png

in order to control the transmitter.

We are of course considering the situation where the MEPT transmitter is an old SSB radio,
typically a recycled commercial transceiver (Codan etc) but it could also be an old ham
rig. But watch for stability issues, especially in older VFO rigs!

The audio file is made using a .BMP to .WAV converter (graphics image to audio) such as
MEPT Controller V1.09 by Con ZL2AFP (preferred) or Chirppix by Marcus DF6NM.
<P>
The generation of suitable files for Visual MEPT use was pioneered by me (Murray ZL1BPU).
me. All I did was fiddle with the parameters until the best results were achieved. This
process is comprehensively described in the HELP information for the PC equivalent program
WAVMEPT, which you can view at:

http://www.qsl.net/zl1bpu/SOFT/WAVEMEPT.htm#WAV

The bit about making .WAV files is titled 'Making .WAV Files', as you might imagine!

To a large extent this involved process has now been superceded by MEPT Controller V1.09,
by Con ZL2AFP, and encouraged by me. This is now the preferred way to make .WAV and then
.MP3 audio files.

RFO BASIC!
----------

The secret to this design is that the controller operates in RFO BASIC!, which can be
downloaded from the APP Store. I have it running on a Samsung tablet, an Asus Nexus
tablet, and even on a cheap Android mini PC (the size of a dongle).

Once you have RFO BASIC! running, you are ready to type in the simple program below, and
modify it to suit your purposes. RFO BASIC! is spretty versatile, and I'm sure you'll
soon think of a host of other ham applications for it.

The Program
-----------

This simple program was written first by Andrew ZL1WJQ and has then been adapted by me.
Yes, there are really only 28 lines of code!

Copy and paste the program, or manually type it into your device and then use RFO BASIC!
to run it. You will need to patch a few things, especially the WAV file name. 

The file name used here is a sample file available from:

http://www.qsl.net/zl1bpu/SOFT/2T_dual.wav

----------------------------------------------------------------------------------------

! MEPT Player by ZL1WJQ

! Check if the next scheduled event is due:

FN.DEF NEXTSCHEDULED(Minute)
	TIME Year$,Month$,Day$,Hour$,Minute$,Second$,Weekday$,isDST
	IF MOD(VAL(Minute$),10 = Minute THEN
		PRINT Hour$;":";Minute$
		FN.RTN 1
	ELSE
		FN.RTN 0
	END
FN.END

WAKELOCK 1

DO
	! Load the MEPT WAV audio file
	n = 0
	Audio.LOAD n, "2T_dual.wav"	!Patch this with your file name

	!Wait until 1 minute past the 10 minute interval

	PRINT "Waiting for next scheduled event ..."
	DO
		PAUSE 1000
	UNTIL NEXTSCHEDULED(1)	!Patch this number to set how many minutes it waits

	! Play the loaded MEPT file
	PRINT "Playing ..."
	AUDIO.PLAY n
	PRINT "Waiting for message to complete ..."
	DO
		PAUSE 1000
		AUDIO.ISDONE isdone
	UNTIL isdone
	PRINT "Message complete"
	AUDIO.STOP
	AUDIO.RELEASE n
UNTIL 0