can you set frequency this way

[metal mania]

Hi im a noobie so I hope you dont mind I shoot an idea for setting the frequency could u use a colpitts hooked with a 10khz crystal instead of the usual caps and resisitors thanks

Just noticed 10khz isnt a cystral size how about a 32khz one is there a way to split it by 3 for instance

[golfnut]

Hi im a noobie so I hope you dont mind I shoot an idea for setting the frequency could u use a colpitts hooked with a 10khz crystal instead of the usual caps and resisitors thanks

Just noticed 10khz isnt a cystral size how about a 32khz one is there a way to split it by 3 for instance

The reason the colpitts is popular is, the Tx coil forms part of the resonant transmit system and the large circulating currents that oscillate between the Tx coil and associate cap give the mag feild required for a reasonable low power Tx.


If you swap out the Tx coil and cap for an xtal then where dya put the Tx coil? Xtals are very high impedance and there wouldlt be much available current flow, so little mag feild.

The xtal oscillator cct would req buffering into the coil load - in order to push some current thru it. The Tx coil could be either resonant or not depending on the drive cct.

The Tx freq is important and influences what you would find.


I have used 32k watch oscillators divided in a D type ff for 16k Tx.

S