My son want to make a simple DC voltmeter on 0-10V range by Convert a galvanometer to voltmeter.Galvanometer DC1mA is cheap and easy with one resistor only.
This is FM transmitter circuit without Coil,using inverter digital IC as main and controlled frequency is precise by crystal. Figure 1 the circuit diagram In Figure 1 is RF oscillator circuit which use a inverter IC1/2 and ceramic crystal filter 10.7 MHz to use drive IC1/4 – IC1/6 by through …
The TA8225 is BTL audio power amplifier for consumer application. It is designed for 45W high power. Operating supply voltage: VCC = 9~18V
Here is ic 555 inverter circuit. is easy and small size. Because use NE555 and MOSFET as main. When use source is 12V battery will have output of 100 watts.
the Automatic LED solar Light is version 2. It has a higher performance, is brighter, compares the version 1. Because we use LED grow use a 12V battery
This is 3W solar LED light circuit made by my son, at day solar charge to battery then night LED light up without AC line, Relay control the solar current
These are four 1.5V FM transmitter circuit (low volt) which use transistor and a few parts, without PCB but easy to build for output 88-108MHz or 90-100MHz, more circuits below