This well-known circuit version of the siren was obtained in a Colectro Handbook from the 70s. The transistors are of general use, with Q2 being a BD136 for greater power with power from 6 to 12 V.
Suggested by Linear Technology in a documentation of the 90s, this circuit is connected to the...
For the 7 to 10 MHz band L1 is formed by 3 turns of 22 to 28 AWG wire in a ferrite core 15 to 20...
We found this circuit in the Texas Instruments' Linear Circuits Applications. It uses an...