sschiesser
Member
...perhaps can someone help me here...
My audio recorder (Teensy 3.6 + Audio shield) works fine, one can independantly record and/or monitor the audio signal and the saved data on the SD card is clean.
I also added at Bluetooth module (BC127 from Sierra Wireless) for remote control and wireless monitoring (line out signal is split to BC127 audio in). That works also fine WITH ONE EXCEPTION: when recording is running, the Bluetooth audio is very noisy (loud buzz, some artifacts). Again, the recorded files on the SD card are very clean, but monitoring doesn't make sense under these conditions.
I have a 4-layers PCB with two of them only dedicated to GND. The Bluetooth module is as far as it can from the Teensy (about 10 cm). And the line out tracks run along the teensy and come close to the pins 13 & 14 (see picture)... since pin 14 ist SCLK of the SD card, could that be the cause? Or should I look somewhere else?
Thanks,
Sebastien
My audio recorder (Teensy 3.6 + Audio shield) works fine, one can independantly record and/or monitor the audio signal and the saved data on the SD card is clean.
I also added at Bluetooth module (BC127 from Sierra Wireless) for remote control and wireless monitoring (line out signal is split to BC127 audio in). That works also fine WITH ONE EXCEPTION: when recording is running, the Bluetooth audio is very noisy (loud buzz, some artifacts). Again, the recorded files on the SD card are very clean, but monitoring doesn't make sense under these conditions.
I have a 4-layers PCB with two of them only dedicated to GND. The Bluetooth module is as far as it can from the Teensy (about 10 cm). And the line out tracks run along the teensy and come close to the pins 13 & 14 (see picture)... since pin 14 ist SCLK of the SD card, could that be the cause? Or should I look somewhere else?
Thanks,
Sebastien