alternate oscillation methods

[metal mania]

alternate oscillation methods can we discuss the pros and cons of the various method's or even discuss a hybrid method say a colpitts using a cystral as a referenced point.

[Skippy]

I don't know if any commercial detectors do this (it is likely), but injection-locking a free-running LC oscillator to a stable reference should produce a low-distortion transmitter with high stability. The source of the reference would normally be a divided-down quartz crystal, but could be microcontroller-generated.

[6666]

Crystal-controlled Colpitts oscillator
http://wps.prenhall.com/chet_paynter...26330-,00.html

[golfnut]

I would like to build a non resonant H bridge type Tx - fed from a tcxo


S

[Tepco]

You certainly don't need TCXO for this, but for relatively low power H-bridge driver, there is one cheap and simple single component solution: TC4421 gate driver chip, used alone, no mosfets or additional components needed (ok, decoupling capacitor or two). Bit limited by around 2Ohm resistance of internal transistors and small DIP8 package dissipation, but good enough for VLF use, no high power needed. I tried it in both square wave and resonant drive (modification of Russian KROT detector), worked just fine, last one is series resonant, producing 60Vpp across the coil, powered from regulated 5V. Also, level shifter is already included, will work driven with 5 or 3.3V powered MCU signal directly, not bad for single component TX.