Audio: wein sine bridge
Feb/24 2011
this is a simple audio signal source for testing audio project. output 1khz, wein bridge sine generator.
performance:
1) 1khz with distortion about 1%
2) output level from 5mVpp to around 1Vpp
use a lamp for gain control, total THD about 1%. it can be better if a suitable lamp is used. but gain stable will take a noticeable time period, so it not so smooth to use as signal source. and occasionally it stop work, because there is no voltage regulator, some time power by wrong supply voltage.
*VCC=9V
*U$3,4 use for adjust the frequency
*U$2 use for adjust feedback
*U$1 with a buffer give a adjustable output level control
conclusion:
1. I hate gain set up time introduced by lamp heat.
2. No box for this, some day i will tear it down( come to reality @2012/9 )
3. poor supply design.
temporally use if you really need one for quick testing.