This is an easy, low cost and easy built circuit of an electronic horn which is designed close to quadruple op-amp IC LM3900 (IC1). IC LM3900 has four independent operational-amplifiers (A1 through A4) having a large output voltage swing. It is able to operate at up to 32V DC. The 1st op-amp (A1) is designed… Read More »
This is the diagram of heat detector circuit which already integrated with siren circuit in the output. This circuit applies a complementary pair comprising NPN metallic transistor T1 (BC109) and PNP germanium transistor T2 (AC188) to detect heat (because of outbreak of fire, for example) in the area and activate a siren/alarm. The collector of… Read More »
This the Good Quality FM transmitter for your stereo or any other amplifier gives you a pretty good signal strength up to a range of 500 metres having a power output of about 200 mW. This circuit can be operated with a 9V battery. The audio-frequency modulation stage is constructed close to transistor BF494 (T1),… Read More »
This is really a very simple home telephone ring tone generator circuit which is built with applying only several electronic components / parts. It generates simulated telephone ring tone and requires only DC supply with 4.5V DC to 12V DC voltage. One may possibly use this circuit in ordinary intercom or phone-type intercom. The sound… Read More »
This is the schematic diagram of DC motor speed controller circuit. The circuit applies two oscillators/timers which are connected as a Pulse Width Modulator (PWM). The timer chip which applied in this circuit will be an nmos dual timer/oscillator NE556. This timer IC has two 555 timers in a single 14-pin IC package.
Here the simple schematic of multitone siren alarm circuit. This multitone siren is effective for reverse horns, burlgar alarms, and many others. It generates five various audio tones and is much more earcatching than a single-tone siren.
This is the FM transmitter circuit which apply 4 radio frequency stages, that are a VHF oscillator designed around transistor BF494 (T1), a preamplifier designed around transistor BF200 (T2), a driver designed around transistor 2N2219 (T3) and also a power amplifier designed around transistor 2N3866 (T4). A condenser microphone is wired at the input of… Read More »
The Univibe is actually a footpedal-operated phaser or phase shifter for generating chorus and vibrato simulations for electric organ or guitar. It was introduced in the 1960s by Shin-ei, and was intended to emulate the “Doppler sound” of a Leslie speaker. Although not a really successful Leslie-simulator, the Univibe has turn out to be an… Read More »
1000W Power Inverter circuit diagram: This is the power inverter circuit based MOSFET RFP50N06. The inverter capable to handle loads up to 1000W, it’s depended on your power inverter transformer. The RFP50N06 Fets are rated at 50 Amps and 60 Volts. Heatsink is required for cooling the MOSFETs. You may add some MOSFETs with parallel… Read More »