9: Volt Battery
2 Comments - in Telephone
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!
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.
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
Easy to build sound effect generator kits, inludes several different sounds and tunes.
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.
0 Comments - in DC Power Supplies
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 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
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.
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.
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
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
A powerful little circuit with surprisingly good audio quality. Can transmit up to 1/2 mile in open spaces. This is one of the most powerful FM transmitters that you can legally purchase. An electret microphone is used to add sensitivity. The circuit come
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
Both a touch and a contact switch are built on one PC board so that the builder can see how each works. A battery can power the contact switch but you'll need an AC power supply for the touch switch to work well. The circuit switches a relay with a 3 Amp
The most popular use for this kit is to make you own night-light. It can also be used to switch just about any appliance on or off in light or darkness. Light sensitivity is adjustable over quite a range. The relay can handle up to 10 Amps at 110VAC. Oper
An entry level programmer and a terrific educational aid. The 16C84 micro-controller from Microchip Technologies has become very popular with hobbyists and beginners. Does not require U/V light to erase programs; programs are erased electrically and the c
Pressing the switch while a dual LED is green advances you to the next stage, but mess-up and press while red, and you go back to the beginning. It can be tricky and a challenge. Fun and teaches some practical basic electronics. Operates on 9V battery.