MMDVMCAL is a very versatile tool included in the latest versions of the pistar software. MMDVMCAL will allow you to check BER (Bit Error Rate), send test tones, adjust TX levels for proper deviation and more.
To access MMDVMCAL, open your pi-star dashboard for your hotspot in a browser window.
Navigate to the “Configuration” page.
Next Navigateto the “Expert” page.
Next Navigate to the “SSH Access” page.
At this point you will be prompted to enter your pi-star credentials.
The defaults are: Username “pi-star” Password “raspberry”.
After a successful login you should see the following.
Type “sudo pistar-mmdvmcal” at the command prompt and Enter.
You are now in the MMDVMCAL program. At this point, your hotspot is disconnected from the network and is in test mode. Commands are CASE SENSITIVE! Capital letters and lower case letters do different things!
E or e – This allows you to set the frequency. Set this to the frequency you normally have your hotspot set for. You need to enter the entire 9 digit frequency. For example 441.5mhz = “441500000”
b – This will put you in a BER test mode for DMR. When you key up the hotspot with your radio, MMDVMCAL will show you the BER for the last transmission. (Any TG that you normally use on this hotspot will do as long as its has CC1 set. Again, nothing will be sent over the network.)
F – This increases your frequency offset
f – This decreases your frequency offset
Adjust the offset with F and f until the BER test mode shows the lowest possible BER.
q – This will quit the program, which upon closing, will print out the offset and some other data and return the hotspot to normal operation.
NO CHANGES ARE MADE TO YOUR PI-STAR CONFIGURATION BY THIS PROGRAM!
This offset can now be put in the RXoffset and TXoffset in the MMDVMHost menu.
Dashboard -> Configuration -> Expert -> MMDVMHost / Modem Section
Tutorial courtesy of kh7ms.
