SKU: 110062

Audible alarm model

Regular price €5,19
Sale price €5,19 Regular price
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Model of an audible alarm that produces a typical siren sound. When the button is pressed, a sound is emitted. When the button is released, it changes tone. Supplied without a 4.5 V battery. The two transistors BC 558/557 and BC 547/548 are assembled to form a simple amplifier. If the output signal of the amplifier is redirected to the input, which is done here through the 0.15 mF capacitor, a voltage variation will oscillate the circuit. The frequency slide characteristic of sirens is caused by an RC circuit through the 10 kOhm resistor and the 100 mF capacitor. The two capacitors parallel to the speaker contribute to the fidelity of its sound by attenuating the high frequencies. The tone is determined by the 27 kOhm resistance, the 0.47 mF capacitor and the speaker impedance of 8 Ohm.

Recommended age

12+

Construction time

3 - 4 h.

Tools

Download instruction manual.

Pairs well with

NOTICE: If the box/packaging is dented or damaged, and/or the protections are broken, this observation must be indicated on the carrier's delivery note. Once the goods have been delivered, and without any incidents on the carrier's delivery note, the customer will be responsible for any visible damage.

After receiving your order, you have 14 working days to exchange or return the product(s) purchased. This option is valid for the vast majority of items available on the website, with the following exceptions:

  • Items that are made to order, according to the customer's instructions, cannot be exchanged or returned;
  • Items whose sale involves installation on site cannot be exchanged or returned;
  • Items that are damaged due to use, are not in their original packaging, or are incomplete cannot be exchanged or returned.
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