Mainboard dad

[Titanus]

Hi,
i was very happy with my (tru)sdx until now. I haven´t used it since 2 weeks, I turned it on and nothing happened suddenly, black display, little noise at the beginning and I realized that the Atmega chip becomes very hot. Power supply was an usb powerbank. The (tru)sdx was ordered as preassembled.


Had anybody also that issue?

I will order now only the mainboard kit.

[dl6sez]

Hello OM,

this sounds like you killed your Atmega328 by ESD.
The Atmega328 does not die by himself. We still have very dry air today and all connectors go
directly to the Atmega328 without further protection circuits.

73 de Chris

[Titanus]

I build yesterday a new mainboard, now it is working. I was wondering that on the new mainboard the reference frequency was at 27001400 on the old one it was at 2700800. Are these differncies in the production?

[Ohwenzelph]

Sounds like differences in crystals, few are spot on, one was off ~800 hertz (assuming you meant 27000800).And the other was off ~1.4 kilohertz. Out of 27 million that’s pretty close. you might be able to buy crystals that are closer to the nominal value but I bet they would cost a lot more. Having the ability to tell the rig a number for calculations that’s very close to your crystals actual value means the number on your dial can be be very close to actually correct without having to obtain super precise crystals. A good trade off and work around. If it’s not dee add…