Balloon Track can sound alarms for several events.

For this feature to work you must have a recognizable sound card and have specified WAV files for each alarm to be played.

Enter the values for the parameters you want the program to monitor. Place a checkmark in the "Sound xxx Alarm" to activate the alarm. If you place a checkmark in the auto cancel box, the program will sound the alert the first time the parameter is exceeded. It will then cancel any future alarms. If you wish to be notified for each violation of the parameter, leave this box unchecked. The Lift Off alarm will sound when the first packet received indicates an altitude 400 feet or more above the altitude entered for the launch location. The Burst Alarm will automatically reset if the ascent rate ever exceeds 500 feet a minute in vertical velocity after detecting a burst (negative ascent rate).

In the case of the "Landing Alarm", the program must be reporting a negative ascent rate and the current altitude must be LESS THAN the value you enter.

For the GPS Error alarm, the program examines the NMEA strings $GPGGA and $GPRMC. There are flags in those strings that indicate the validity of the data contained within the strings. See the NMEA Faq at the EOSS website for specifics. Check out the 6th field in the GGA string and the 2nd in the RMC. When one of these flags indicates a problem with the data, the alarm sounds.

If an alarm has been automatically cancelled you can reactivate it by simply opening the Alarm Screen and toggling the sound alarm check box. If you change a value for an alarm that has been auto cancelled, it will automatically be reactivated. If you wish to reset all automatically cancelled alarms press the Reset Alarms button.

Sound files MUST be wav files. Click the browse button beside each alarm and specify which wav file you wish played.

You can preview it by pressing the Play button. There is a minor bug here I'm working on correcting. When you click Play the label on the button changes to Stop. So, if you inadvertently click on a really long wav file you won't have to listen through to the end of the file. The bug? Well, playing the wav file is a system call and I haven't yet discovered how to get an event notification on the completion of a wav file being played. So, the label on the button remains "Stop" even after the wav is finished. And if you click it or another button nothing happens. That is because the program thinks a wav is still playing and sends the command to stop that file. Click it a third time and you can once again play a file. If you click Stop prior to the end of a wav file, the wav will stop and the label will revert to Play. I'll fix this sooner or later.

Initially I only had one alarm sound. However, it became confusing just hearing a siren going off. So, I've added the ability to set an individual sound to each alarm. I recorded my voice saying "Burst Alarm", "Ascent Rate Alarm", etc. Now when a parameter is met, I get a voice prompt that is indicative of the event that just occurred. I recommend you make your own alert sounds, however here are sounds for each event above.