On Tue, Apr 1, 2025 at 07:54 PM, Michael Shiplet wrote:
However, the measured voltage across R105 went from ~3V (normal operation) to ~4V (frozen)
Michael, where did you connect the GND probe of your Meter to the QMX GND?
3 V ... 3.3 V would be ok. This signal comes direct from a controller I/O-pin and the controller runs from VDD 3.3 V. 4 V is wrong. Maybe VDD is going wrong after a few minutes. This would be dangerous for some IC especially the controller. Could you measure VDD. You may use JP105 to contact VDD. But TAKE CARE not to connect VDD to "+12V". This would destroy some important elements.
Could you measure the supply current from the beginning until the QMX stops?
Could you check temperature of IC101? But please take care it could be hot.
?
I would avoid to transmit in the moment.
?
73 Ludwig
