More about technology (448)

| Nickel-metal-hybride (NiMH) batteries have now become widely available. A typical one is the 120AAH, which has a capacity of 1.2 Ah in si...

| Many battery-operated appliances have an LED indicator that shows the state of the battery. If the battery is almost flat, the LED flickers....

| A simple unit for testing an audio, TTL or CMOS circuit is always useful. Here, an oscillator, based on IC(1a), generates a frequency tha...

| The UAA2016 from Motorola lends itself admirably to making a proportional mains-operated temperature control. A resistor with negative tem...

| The tester cannot only detect rectangular-wave signals. It can also generate them. The test signals may be generated continuously or for a...

| Based on only two ICs and a transistor, this circuit can perform three test functions selected by switch S1.

| This audio-frequency receiver is the counterpart of the infra-red transmitter. The output from the infra-red diode D1 is amplified by IC1...

| The aim of the design of this 'zener diode' is to obtain a fast voltage regulator that can provide high currents. The circuit is based on...

| All I²C cards published so far in this magazine are normally powered by the 5 V supply in the PC via the 6-way DIN socket on the 12C PC...

| Halogen lamps are rightly popular because they give a good light and have an excellent efficiency. Unfortunately, they tend to be costly....