This is iKHz sine beachcomber architect ambit congenital based on agreement of astern Wien arch (see C1-R3 & C2-R4). R5 and R7 acclimated for achievement amplutide setting. Set R5 to apprehend 1V RMS on an Audio Millivoltmeter affiliated to the achievement with R7 rotated absolutely clockwise, or to appearance a sinewave of 2.828V Peak-to-Peak amplitude on the oscilloscope.
R1____________5K6 1/4W Resistor
R2____________1K8 1/4W Resistor
R3,R4________15K 1/4W Resistors
R5__________500R 1/2W Trimmer Cermet
R6__________330R 1/4W Resistor
R7__________470R Linear Potentiometer
C1,C2________10nF 63V Polyester Capacitors
C3__________100µF 25V Electrolytic Capacitor
C4__________470nF 63V Polyester Capacitor
Q1,Q2_______BC238 25V 100mA NPN Transistors
LP1___________12V 40mA Filament Lamp Bulb (See Notes)
J1__________Phono chassis Socket
SW1__________SPST Slider Switch
Clip for 9V PP3 Battery
- The bulb must be a low current type (12V 40-50mA or 6V 50mA) in order to obtain good long term stability and low distortion.
- Using a bulb differing from specifications may require a change of R6 value to 220 or 150 Ohms to ensure proper circuit's oscillation.
- With C1, C2 = 100nF the frequency generated is 100Hz and with C1, C2 = 1nF frequency is 10KHz but R5 requires adjustment.
- High gain transistors are preferred for better performance.