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jweers1 / Aprs-Tracker

APRS Tracker
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Packets being transmitted are exhibiting "Slow down" #1

Open sharkyza opened 5 years ago

sharkyza commented 5 years ago

I have been trying to resolve why no packets sent from my circuit built as per documentation could be decoded. I hooked up an oscilloscope and noticed that the packets being transmitted did not purely consist of the 1.2 & 2.2kHz tones but had a lower frequency tone included at random during the transmission, but with every transmission.

I came across this old reddit post and think it could be related https://www.reddit.com/r/amateurradio/comments/494467/libaprs_stroller_tracker_how_i_got_it_working/

Problems with SoftwareSerial Once I got the Micromodem schematic and LibAPRS working good with sending packets with the radio I hooked up a Ublox neo-6m GPS module using SoftwareSerial at 9600 baud on port 11 and 12. The GPS worked good and sent serial data that was parsed fine with TinyGPS++. When I hooked in the radio however I could hear the packets sending very slow, like a packet being sent in slow motion over a few seconds in stead of less than a second. They weren’t decoded of course on my other radio. My guess is that there was interference between LibAPRS and SoftwareSerial? I then tried different ports on the Nano without success. After that I tried AltSoftSerial, the difference then was that the sound of the packets was a bit faster but still slow and no packets decoded. In the end I used the hardware serial port RX0 on the Nano and removed SoftwareSerial, now everything works good both GPS and sending packets.

Has anyone else noticed this?

I am using an Arduino Nano clone 328P @ 5V 16MHz

Wosacz commented 4 years ago

Without a chance? Only with HW Serial?