New release of MULTIPSK (4.39.1) #Multipsk
New release of MULTIPSK (4.39.1)
Pour les francophones: la version en français de ce message se trouve sur mon site (http://f6cte.free.fr). Il suffit de cliquer sur le lien "Principales modifications (courriel avertissant de la sortie de la nouvelle version)".
* The new release of MultiPSK (4.39.1) is on my Web site (http://f6cte.free.fr/index_anglais.htm).
* The MD5 signature of the downloaded MULTIPSK_setup.exe file to, possibly, check (with WinMD5 for example), that the downloading works without error, is equal to: 7cd16b8616ec0883bdd11962a37edcbd
* Multipsk associated to Clock are freeware programs but with functions submitted to a licence (by user key).
The main improvements of MULTIPSK 4.39.1 are the following:
Addition of TCP/IP interfaces: "SRDplay" and "rtl_tcp.exe"
Pushing on the "SDRplay" or "rtl_tcp.exe" button of the "Configuration" screen permits to interface:
· either a SDRplay receiver, thanks to the TCP/IP server "rsp_tcp.exe",
· either a TNT receiver or compatible, thanks to the TCP/IP server "rtl_tcp.exe".
The frequency and the gain are adjustable through this interface.
The I/Q signal is taken from the receiver (TNT or SDRplay) through the TCP/IP server, at a sampling frequency 250 KHz, in the local loop adress: 127.0.0.1, port 1234. The TCP/IP adress and the port are configurable.
Improvement of the EGC decoding
The EGC (Enhanced Group Calls) service of Inmarsat C satellites uses the PSK modulation at 1200 bauds to send broadcast messages either to all ships or to ships located on a given area, from a NCSC (Network Control Station Channel). The geostationary Inmarsat satellites 4-F3, 3-F5, 4-F1 and 4A-F4 use frequencies around 1540 MHz for these transmissions
Necessary hardware: for these UHF frequencies, a stable receiver and without not too much shift is advised (RTL/SDR key as "RTL-SDR.COM V3", for example). A LNA ("Low Noise Amplifier") is necessary. It must be placed at the antenna output. A LNA specific to band L is advised. The antenna can be a Patch one or a helical one (right-hand circular polarization).
Note about translation of Multipsk.exe and Clock .exe: the 4.39 version of Multipsk has been translated to Spanish by Joachin (EA4ZB), from French.