Looking for more info about open loop method

[elkimhoc]

open loop method

hi,
who know more about the open loop method to build oscillator,
it a method to control exactly the amplitude, power and other parameters of oscillator.
Any ebooks about that ??

 

[biff44]

Re: open loop method

Works pretty good at lower frequencies, like 500 MHz. You build an amplifier with a coupler at the output and a 2port transmission resonator. You hook these parts together, attach them to a network analyzer, crank up the s11 power as high as the analyzer can go, and measure S21. If, at resonance, S21 is > 2 dB and the phase angle is 0 degrees, you simply connect the output to the input and you are done.

If the phase angle is not 0 or N*2Π degrees, you add phase length with a lowpass filter, highpass filter, or short transmission line.

 

[elkimhoc]

Re: open loop method

yes but is it work at 4 GHz, with MMIC circuit ?