Touch Switch

Experiment With NAND Gate - CMOS 4011

Output goes high when touch wires bridge by finger.

Gates Oscillator

Experiment With NAND Gate - CMOS 4011

(CMOS 4011 Layout)

Circuit

Try this super-simple experiment. The output frequency is about 1kHz (square wave).

The NAND output is on CH1 (bottom), CH2 (top) is the test signal 1kHz.

Telephone FM Transmitter

Descrition & Circuit

This project is taken from www.electronics-lab.com.
With some modification, I create my own version of FM Telephone bug complete with stripboard layout.
Theortically, the frequency range is from 88MHz to 94MHz but you may experiment with the coil structure to tune it

Circuit

Strip Board Layout

Parts List

Diode	IN4384	4
	LED	1
Resistor	12k	1
	1k	1
	200R	1
Capacitor	470p	1
	330p	1
	25p	1
	12p	1
Transistor	A933(PNP)	1
Coil	*See note	1

*Coil note
7 or 8 turns of 22AWG(diameter .6mm) around 9/64inch(3.6mm) drill bit. Antenna using the same wire 22AWG, 5inch long

Picture

Compact!


With antenna!

Put it online!

Get ready to tune your radio!

Lab Power Supply

Description and Circuit

Make your own lab power supply complete with adjustable voltage and constant current source.
Using single IC (LM324)
Here is the circuit.

Strip Board Layout.

Part List

1 LM324 Opamp
1 Ammeter 100 µA 1k ohm
1 Voltmeter
6 IN4001
1 Zener Diode 9.1V
1 Full-Wave Bridge Rectifier
1 LED
2 NPN Transistor, 2N3055
1 NPN Transistor, BC109C
1 Transformer
2 E-Capacitor 2200µF
1 Potentiometer 5k ohm linear
1 Potentiometer 10k ohm linear
1 Resistor 500 ohm
2 Resistor 2.2k ohm
1 Resistor 560 ohm
1 Resistor 6.2k ohm
2 Resistor 68k ohm
1 Resistor 0.22 ohm
4 Resistor 4.7k ohm

Component Image.

LM324

2N3055

Some Pictures.