Page 1 of 1

SOLVED: MMDVM_POG REPEATER LOCKING PROBLEM

Posted: Mon Jul 13, 2020 3:38 pm
by PU4RON
Hello! The problem of the MMDVM_POG card that crashes and stops working after a certain time when receiving transmissions via RF was solved using a SI5351 module and an aduino pro micro to manage the module. The problem is related to the TCXO at 19.2 MHz. The entire circuit was removed from the txx and the generator signal was applied at point Tp61 of mmdvm_pog. The result with si5351 was excellent, showing stability and with possibilities of frequency correction. The SI5351 module in 12MHZ showed better performance and does not make the MMDVM_POG board have the problem of locking and improves the quality of the BER.

https://github.com/pu4ron/mmdvm_pog

Ronualdo - PU4RON
BRAZIL

Re: SOLVED: MMDVM_POG REPEATER LOCKING PROBLEM

Posted: Mon Jul 13, 2020 6:22 pm
by KE7FNS
Why not just use the RPi to communicate with the si5351 using i2c? You could completely eliminate the Arduino.

Re: SOLVED: MMDVM_POG REPEATER LOCKING PROBLEM

Posted: Sat Aug 01, 2020 1:18 pm
by PU4RON
The RPI is more susceptible to failure than an arduino for this type of function. If for any reason the SD card fails or an error occurs on the RPI's i2c, the MMDVM card will lock up and the PTT will be active.