Hi
I have a crystal clocked microcontroller with capacitor arrangement much like any other.
I’ve heard years ago that if I have a better clock source (in this case TCXO with TTL output),
it’s possible to attenuate that, and connect it directly to the clock input pin with the crystal still in place,
and that the new signal will correct the crystal oscillator to become a more accurate clock.
If this is true, does it matter that the TCXO is TTL?
With some series resistance, will it drag down the original crystal much when the TCXO circuit is switch off?
I ask the second question because I assume the TCXO is a drain on batteries while it’s operating heating up a resistor oven.
Cheers.