The resonators used on the Nano clones are less accurate?and much easier to move in frequency than the?quartz crystals used on the original Arduino Nano.
The datasheet for a Murata CSTNE16M0V530000R0 ceramic resonator says it has an accuracy of +/-0.50%, and can drift over its temperature range of -40C to +85C by up to another +/-0.30%
The Murata?XRCGB16M000FXN00R0 16mhz quartz crystal has an accuracy of +/-40ppm, including variations due to temperature.? So?100*40/1e6 = 0.004%, 125 times more accurate.
If pulling does not work, might replace the resonator with a quartz crystal near but not on 16.000mhz,? perhaps 15mhz or 16.384mhz.
Or drive the processor clock pin from a quartz crystal oscillator.
A different clock frequency would change timing determined in Arduino firmware, such as CW keying speed.
I would not know what all this might affect on current firmware, but doubt it's catastrophic.
Jerry, KE7ER
On Mon, Nov 2, 2020 at 06:26 AM, Jerry Gaffke wrote:
The Raduino comes with a $2 Nano clone using the CH340 chip for the USB-to-UART interface.
Not the $20 original Arduino design.? Here's a description and a schematic:
Note that there are pads for caps on each side of the resonator, but they are not used.
