6: Volt Battery Meter

This LCD panel meter is a very flexible design that can be customized to your own VOLT meter or AMP meter needs. It may be customized to measure any voltage range, standard or not. Or you can customize it to measure input from a transducer; full details a

This temperature meter uses a Harris 7106 IC as the heart of a low cost, accurate temperature meter. LCD 3-1/2 digit readout. All of the active circuits are in this one, versatile chip. In addition to temperature functions, the board includes an area for

A very clever portable cell phone battery charger that uses 8x1.5 AA cells (batteries) to charge cell-phone / mobile phone batteries while mobile. No more need for a mains outlet!

The most powerful circuit we've seen that operates on such low voltage (just two AA cells). A range of 100 meters can be expected and, given a good antenna and FM receiver, 500 meters can be expected. An external power supply can be used up to 9 volts. Tr

The most powerful circuit we've seen that operates on such low voltage (just two AA cells). A range of 100 meters can be expected and, given a good antenna and FM receiver, 500 meters can be expected. An external power supply can be used up to 9 volts. Tr

An educational learning module. Build and experiment with the astable, monostable and RS flip-flop multivibrators on one PC board with six LED's. Understand exactly how each one works. Operates on a 9 Volt battery.

This is a basic low cost counter module. Two or more may be plugged together with 6-pin sockets and harness provided. Excellent use as event counter. Has a single 3-digit display. Uses the 14553 and 14551 chips. Has count and reset switches with debounce

Schematic for an electronic audio level VU meter that uses LED's to display the volume/audio levels.

This LCD panel meter is a very flexible design that can be customized to your own VOLT meter or AMP meter needs. It may be customized to measure any voltage range, standard or not. Or you can customize it to measure input from a transducer; full details a

Using ultrasonic techniques, this solid-state design has no moving parts.

Easy to build sound effect generator kits, inludes several different sounds and tunes.

Old time style with the following options: 20,000 ohm/Volts, 19 Ranges, 3.5 Meter, dB Scales, Audible Continuity, Battery Tester, 10A DC Current.

Teaches the fundamentals of a basic robotic sensing and locomotion principles while testing motor skills. Includes 5 switch wires controller to grab, release, lift, lower, rotate wrist, and pivot sideways 120°. Transparent arm shows the state-of-the-ar

An extremely simple and cheap DC power supply with variable voltage (1.2-25 Volts) control. The circuit uses an LM317 integrated voltage regulator Ic.

A very simple variable power supply with a DC output voltage adjustable from 1-3- Volts, with a maximum DC current of 5 Amps. Uses LM338 DC voltage regulator IC.

A very basic power supply that can be adjusted over a range of about 1.5 to 35 volts DC. If you add a heat sink (included), you can run it as hot as 2 Amps output; otherwise about 60 mA @ 12 volts. This is a text book circuit using an LM317, which is a 3

This is a very eye appealing audio accessory. Displays an approximate output level for each channel of a stereo amplifier. Connects to the speaker terminal; levels are displayed in ten steps. User may select either a moving dot bar appearance. Uses two LM

A bright, variable flash rate strobe light. This is a 9 Volt battery powered xenon tube flasher. A small circut is easily transported for camping etc. Flash rate may be varied between 1 and 4 flashes per second.

Flashes five very bright LED's in any one of seven, user-selectable, patterns. A COB (chip-on-board) IC makes assembly very easy; the chip is supplied premounted on its own board and a motherboard contains the entire circuit. Operates on 3 volts DC, batte

The circuit flashes five LED's in sequence repeatedly until you turn it off. Flash rate is user adjustable. The circuit uses an IC chip on Board which you will then mount on the included mother board; battery holder is included. Powered by a 3 volt supply

Radiation Alert Monitor 4 Kit or completed unit Geiger Counter