ADJUSTABLE SIREN


Posted on Feb 6, 2014

Tone is made adjustable by using multiposition switch to change capacitors in oscillator circuit. Speed (rate of change in frequency) of siren is adjusted with R3. 4700-ohm resistor in series with R3 keeps siren op-erational when R3 is rotated to minimum-resistance position. Siren is operated by pressing switch to produce rising wail, then releasi


ADJUSTABLE SIREN
Click here to download the full size of the above Circuit.

ng switch until wail drops down to cutoff. -F. M. Mims, "Transistor Projects, Vol. 1, " Radio Shack, Fort Worth, TX, 1977, 2nd Ed. , p 58-63.




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

VU Meter with UAA180
Transistor Checker Circuit
Talking Nixie Alarm Clock
Laser Alarm
JCM800 2204 bias problem
Circuit Audio Stereo power amplifier LM4755 11W with Mute
Sawtooth generator circuit II



Top