Decoding Software:

To be able to send and decode digital information, computer software becomes necessary.   
In this part, I will present some programs allowing the encoding and decoding of digital modes. The software Multipsk can encode and decode digital signals like BPSK31, QPSK31, and MPT1382…

Here is the main page of Multipsk, we can choose the type of modulation in the upper right :

 

 

 

 

 

 

 

 

 

 

 

 

 

• Received messages appear in real time.
• The modes RTTY, CW and PSK are widely used by ham radio on the shortwave bands.
• APRS mode (Automatic Position Reporting System) is used to track the precise delimitation of ham balloons or station to obtain weather information in real time:

Here is the main APRS Window, which allows you to obtain weather information and the position of the balloon or the transmitting station :

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The APRS uses packet radio to transmit information generally on 137,95Mhz in FM mode.

> The mode MPT1382:

The mode MPT1382 is a digital data transmission system widely used by firefighters today.
This mode is widely used in the Band of 86 MHz.

It is used for the connections and alerts transmissions between different firefighter’s barracks of a department.
The MPT1382 can sometimes be encrypted, which is rare.
In this case Multipsk do nothing or will display anything!

 

• The software POCSAG32 for Windows and Linux:

The software POCSAG32 (most generally called POC32) allows you to decode digital modes type POCSAG.
The POCSAG is also a digital transmission system used to broadcast written messages.
The messages are typically received on beepers like that:

This system is widely used by large companies and especially by firefighters.

They can send a clear and precise about the type of mission.

The POCSAG uses multi-speed transmissions: 512, 1200 and 2400 bits/s. The traditional speed is 1200 bits/s.

Here is an example of decoding POCSAG with POC32:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The decoding was carried out on two frequencies 85,955 and 173.5125MHz.
These two frequencies are used by firefighter’s beepers. Using this software, you can be informed of any interventions in the department in real-time.