Mutchus

This FM transmitter circuit can be used as a wireless microphone,  can be received by an ordinary 88- to 108-MHz FM broadcast receiver. For the power supply, this transmitter circuit is powered by a 9 V battery. To comply with the radiation limit of FCC rules, keep the antenna length under 12 inches. L1 is 6 turns of #24 wire wound around a pencil or a 1/4″ form, with turns spacing of 1 wire diameter. C6 is a gimmick capacitor which has value about 1 pF..  9V Wireless Microphone FM Transmitter Circuit Diagram

How to Build a Bipolar Power supply for Battery instruments . A bipolar power supply overcomes those limitations. Most importantly, it can provide both positive and negative voltages from a single pair of terminals. There are no relays to switch polarity, so a bipolar supply can move smoothly from positive, through zero, to negative voltages.   Bipolar Power supply for Battery instruments Circuit Diagram It also regulates zero volts or other very small voltages. In this Bipolar Power supply for Battery instruments circuit diagram to generate regulated ± 5-V supplies from a pair of dry batteries, the circuit of Fig. 1 is commonly used. In order to give protection from inadvertent reverse connection of a battery, a diode in series with each battery would produce an unacceptable voltage drop.  The more effective approach is to fit diodes Dl and D2 as shown in Fig. 2, in parallel with each battery. When the supply is switched off, there is the risk of a reverse bias being ...

An LED is usually a series resistor needed to ensure that the LED does not get too much power. The disadvantage of such a resistor is that the current thus also changes by the LED and the brightness as the voltage changes.  This circuit prevents that, by independent of the voltage, a constant current through the LED.The circuit uses two transistors and two resistors. The circuit can be connected to voltages of from 5 to 24 V.   Constant LED Power Supply Circuit Diagram

Build 32 Watt Amplifier Circuit Using by TDA2050V. A 32 Watt per channel stereo power amplifier made using the TDA2050V monolithic integrated circuit.  32 Watt Amplifier Circuit Diagram Notes: This circuit is for a 32 Watt stereo audio power amplifier using the TDA20501. With a dual 22 Volt supply this amplifier can deliver 32W into 8 ohm loudspeakers. Moreover, the TDA 2050 delivers typically 50W music power into 4 ohm load over 1 sec at VS= 22.5V and f = 1KHz. The amplifier is cased as a Pentawatt package see pinout below: This is a power amplifier and requires 200mV RMS for full output. Voltage gain is 30.5dB with resistor values shown. Closed loop gain is set by Ratio R1/R2. Increase R2 for less gain and vice versa. Power bandwidth is 20Hz to 80KHz. R3, C3 and R6, C11 form a zobel network to prevent high frequency instability. The speaker is direct coupled, therefore no expensive large value electrolytics are needed and the bass will be crisp and clean. It is advisable to plac...

  This cell phone jammer operates at GSM800 frequency since most mobile phones use it to operate. So the selected VCO is a sweeping oscillator, which is very effective but may be hard to construct for the beginners without nice RF-testing equipment. As a noise source you can use 45MHz clock oscillator which is driving Local Oscillator port located on a mini-circuit mixer. There is also an impedance matching network for Local Oscillator signal to pass through it. It is used to equate impedances of the clock oscillator and the port of the mixer. RF input (which is this port of the mixer) connected to the first 800MHz cell phone antenna, and the RF output is sent to the mini-circuit amplifier. This amplifier increases the output power for 15-16dbm. The amplified signal then sent to the second cell phone antenna.  works All cell phones which use GSM800 have their transmitted and received frequencies always separated by 45MHz. So when the mobile phone tries to call it is blocked b...

To get a more precise output voltage, replace zener diode Z1 with 10V and R1 with a 1Kilo ohm potentiometer. A Coolrib for Q1 is optional but highly recommended. You can replace Q1 for a more robust type to get more output amps depending on your requirements. Simple circuit to power your 9 volt cassette recorder and other stuff. Parts List: R1 = 560 ohm C1 = 1000uF/40V, Electrolytic C2 = 10uF/25V, Electrolytic C3 = 330nF, Ceramic Z1 = 9.1V, 1watt zener Q1 = ECG184, NTE184 

A sound generator is a vibrating object which produces a sound. How to Build a Simple Run-Down Clock Circuit Diagram ? This is a simple sound generator circuit diagram this is a simple and easy to use. Enter your desired frequency and press play. In this circuit used in electronic roulette or dice games, this circuit produces a clock signal that initially is several tens of kHz (depending on C2) and gradually decreases to zero in about 15 seconds, as CI discharges through R4.  Simple Run-Down Clock Circuit Diagram

How to build solar charger circuit project with transistors. A very simple solar charger circuit project can be designed using few external electronic parts . This simple solar charger circuit is capable of handling charge currents of up to 1A. Alternate component values are given in the figure for lower current applications. Solar Charger Circuit Diagram: The only adjustment is the voltage trip point when the current is shunted through the transistor and load resistor. This should be set with a fully charged battery. As the transistor and R3 have the entire panel’s output across them when the battery is fully charged, all of the current from the panel will be going through R3 and the Darlington transistor TIP112, so these must be well heat sunk. Adjust R1 for the trip point, usually 14.4 V – 15 V for a 12 V SLA or a 12 V Ni-Cd battery.