Two or more counter modules may be plugged together with the 6-pin sockets & harness provided. Uses a single-unit 3-digit LED display.and is built around the 14553 & 14511 chips. Box & battery are provided. The separate COUNTER MODULE shows how to use the Kit as a counter. Has COUNT & RESET switches with debounce circuit built in to eliminate problems from noisy switches. 9V battery operation.

Introduces 3 1/2 digit LCD and the very popular 7106 IC. This IC has been used in low-cost multimeters for over 13 years. We use it to measure temperature using a ordinary signal transistor as the sensor. Data sheets are provided as is a breadboard area so you can extend the circuit to build your own voltmeter, ammeter, resistance meter or extended-range temperature meter. Takes away the mystery of how multimeters work. Box provided. 9V battery operation.

A kit to introduce you to electronics and circuit analysis. Seven LEDs arranged like a real dice face. Push the switch and the dice rolls then slows down. Ingenious circuit design used to minimise components. Uses 14017 & 555. Box included. 9V battery operation.

Batteries soon become an expensive way to power your electronic kit and electronic games. This is a basic power supply in a box using two 7805 regulators. Input up to 20V AC from a transformer or power pack. Two regulated outputs are available - one fixed at 5V, the other variable. Good introduction to three terminal regulators.

A game of skill to turn on the Stairway of 6 LEDs as the bi- colour LED flashes. Introduces you to several electronics basic circuits with a surprisingly difficult game to play. Box included. Good introduction to electronics. 9V battery.

Electronic game. Ten LEDs in a circle. One LED is turned on at a time to simulate the spinning of a roulette ball around the wheel. Uses voltage controlled oscillator circuit. 'Ball' gradually slows down and stops on a number. 'Ball' speed can be adjusted. Uses 9V battery.

The most powerful 'bug' available for its size, 3V supply and number of components. Guaranteed to transmit over 100 meters within buildings and to 500 meters in the open. Easily tunable in the FM band. Greater range at higher voltage and better aerial.

A learning module. Build and experiment with astable, monostable and SR flip-flop multivibrators on the one PCB. 6 LED's & 9V battery-powered. See and understand exactly how each works. Good introduction to electronics.

Introduces the Optocoupler-triac MOC3021 and triac. Complete electrical isolation between input audio signal (low voltage circuit) and output light modulation (mains supply voltage levels) is achieved.

Can be adjusted to turn on your tape recorder through its REMOTE plug. Has feedback and delay circuit for robust operation. Very sensitive. Proven circuit. Needs 6V plug pack for most stable operation.

Kit contains Xenon Flashtube as found on aircraft, camera flash units, signal beacons and disco lights. Adjust to flash from 1 every three seconds to 3 flashes per second.

CAUTION: Connects directly to mains power supply. Must be put in a suitable enclosed box before using. Two PCBs for different mains voltage.

Miniature transmitter which attaches in series with one of the two lines to your telephone. Transmits over 200 meters to an ordinary FM receiver. Transmits further if the FM receiver is near the phone line. Tune with ceramic trim cap. Uses the phone line as an aerial and power source.

This Kit is designed as a building block in other projects where a battery-powered, variable-gain audio amplifier is required. Up to 2W.

Matched 40 kHz transmitter/receiver pair of transducers detects movement at over 7 metres. Separate PCB for mounting the active units. Latch/reset PCB-mounted switch on board. Sensitivity control. 9V battery operation. Transmitter is crystal- locked at 40kHz for maximum efficiency.

Simple two wire intercom. Each unit with its own speaker, microphone and amplifier (LM386.) Can be modified to a hard wired 'bug'. With 4 strand ribbon cable the power can be sent to the remote 'bug' unit from the receiving unit.

9V battery powered xenon tube flasher. Transformer supplied. Wire is pre-wound on the bobbin but you must do the final winding of two outer coils. Full instructions provided. Trimpot to vary flash rate. Useful and educational.

Good value-for money & simple circuit to generate square, (pseudo) sine and triangle waveforms in the audio range. Uses quad opamp LM348.

This is the most important piece of equipment for testing and measuring digital equipment. It is usually used in fault finding and testing but can also assist in design work and to find out how digital equipment works. Switch for either TTL or CMOS. Our own modern design using a PUT. Includes detection circuit for very fast pulses. Gives visual (3 LEDs) and audio (piezo buzzer) response.

Allows you to send sound through plastic 1mm fibre optic cable. Matched transmitter/receiver pair from Motorola. Two circuit boards with a microphone at one end and a speaker at the other. 14 feet fibre optic cable supplied. Will work over 200 meters.

A 1W power amplifier building block designed to be part of a larger project needing a low power battery operated amplifier into an 8 ohm speaker.

A sound activated switch and an FM transmitter joined together to make a voice activated FM transmitter. Set the level of sound that it will respond to. Two stage transmitter needs tuning to get best results. Tuning Kit and instructions enclosed. Transmits up to 1 km in the open depending on the aerial used.

An introduction to a basic but fully working combination lock. Separate touch pad with 9 pads. Lock is reset if an incorrect digit is pressed. Relay is capable of switching 250V. 12V operation. Robust and versatile.

Circuit designed around a recently developed movement IC the KC778B. Circuit utilizes PIR detector and a light dependent resistor (LDR) to provide an optimized circuit that will detect motion up to 6 metres away. Operates on 9-12 VDC. Note that the PIR sensor & the PCB-mounted fresnel lens fit on the other side of the PCB; the solder side. This is to allow the unit to be mounted inside a container with the detecting lens poking out and the controls facing inside the box.

A surprisingly loud siren for such a simple circuit. Uses voltage controlled oscillator. 1/2 Watt, 8 ohm speaker supplied. 9V operation. Ideal to attach to an alarm system which needs an sound module.

Our most powerful FM 'bug' to date. A two stage FM transmitter with an RF transistor (ZTX320) in the output stage. 9V operation. On/off switch mounted on the PCB.

This kit uses a FET to switch on a tape recorder when the phone is picked up. It will work with low voltage tape recorders as low as 1.5V. It requires the REMOTE & MIC jacks of the tape recorder to be available. Plugs are provided.

Make this general purpose 3 1/2 digit LCD panel meter into your own voltage or current meter or custom-make it to measure voltage input from a transducer. Full details are given in the documentation. Uses the very popular 7106 IC. The LCD section of the PCB may be cut off and mounted separately.

This general purpose 4 1/2 digit LCD counter is built around the 7224 IC. All the 7224 pins are brought out. You can custom design it for your own counter application.

Kit 37M. Five red LED's flash in seven patterns. The modes can be cycled through using an on-board SPDT switch. When the desired flashing pattern is found just leave the switch there and the pattern will remain flashing as long as power goes to the board & the switch remains set. COB PCB measuring 3cm x 1.5 cm. October 2000. Now with trimpot to vary flash rate.

Binary/hexadecimal/decimal/2's complement converter using a K1 uC. Eight LEDs are in a row. Step turns them on in turn by counting up using binary arithmetic. The 3-digit display shows the decimal equivalent (between 0 & 255) of the binary pattern. Press mode and the equivalent hexadecimal value (between 0 & FF) of the binary pattern is displayed. Mode and step pressed together will count backwards. If step is kept depressed the LEDs will rapidly count through the complete binary cycle in about 9 seconds.

But that is only half the capability of the Kit. Pressing mode again will show the 2's complement binary pattern of the previously displayed binary number. The equivalent hex and decimal values of the 2's comp number are also shown on the 3-digit display. Double-sided small PCB, 49mm x 79mm, 1.95" x 3.1". Supplied with box. 9V battery required. Display turns off after 1 minute with no keypress. Complete annotated program code supplied on floppy disk. Reviewed in Electronics Australia, 9/94, p82 - 86.

No description.

Quite often the hobbyist needs to use a relay. The output of some device like a PIR has output pads for the alarm signal which must be connected to a remote switching device. Or sometimes we have a Kit to test which needs a relay connected to it. To fill these needs we have made two Kits which are just a relay, PCB and terminal blocks for the input/output signals. There are many relay pin-outs & drive voltages to select from. We have standardized on two 12V relays from Goodsky. Kit 43 uses a large electro-mechanical relay designed to switch 240VAC/10A. Kit 45 uses two miniature 1A relays.

A proven & popular power amplifier building block for use in any audio project. Power output is dependent on the supply voltage and load resistance. Over 10W is typical for a 16V supply into a 2 ohm speaker. A 12V supply into a 4 ohm speaker will deliver around 4W. Small heatsink provided. In late 2000 the LM383 was discontinued but the TDA2002 is a direct replacement.

Using amplifier modules is modern, quick and easy but it teaches nothing about how they work. Here is a Class AB amplifier made from individual components which will deliver several watts of power into an ordinary 8 ohm speaker. Gives hands-on learning about cross-over distortion, bootstrapping, complementary pairs, and push-pull. Detailed explanations given.

Kit contains the essential components to build a hifi amplifier module using the LM1875 IC. Heatsink, speakers and cables are to be supplied by the user.

No description.

Five Ultra Bright LED's flashing in random or in sequence. Uses a COB (Chip-on-board) PCB measuring 3cm x 1.5 cm. The flashing frequency is set by a single external resistor between 300K and 1M ohm. A pad connected high determines the random or sequential flash pattern. A second pad connected low determines whether the flashing is continuous or set by a toggle switch.

Excellent project for schools since the project is very safe - uses 2 x 1.5V batteries, can be easily put together within 30 minutes, teaches the latest electronic technology as found in games and toys and give an strong visual result when it is finished. Comes with a motherboard to aid attaching the components to the COB PCB.

This Kit continues the pattern demonstrated in earlier K1 micro-controller (uC) Kits (#38, #40, #42) where a uC more than replaces a cluster of logic IC's. In this Kit we have incorporated seven different types of timing operations all in one Kit. The Kit basically only contains 3 IC's. This is less than some timers which only time a single operation! A 4.096 MHz crystal attached to the K1 gives accurate timing. We have included two opto-isolators in the design to allow for a full range of signal inputs ranging from simple push buttons to electrically isolated voltage switching sources.

Time can be counted in steps of 0.1 seconds between 0.1 & 6553.6 sec. (1h 49m 13.6s), or in 1 seconds steps between 1 sec. & 65536 sec. (18h 12m 16s.) On-board DIP switches select start/stop times & timing modes.

Three flowcharts and 4 pages of written explanations are given in the documentation. Double sided PCB 56mm x 97mm mounted on box. On-board 12V relay rated at 5A/240V.

Uses a suction cup to attach to your telephone handset. Picks up the magnetic field produced in the earpiece by both sides of a telephone conversation. Using op-amps is still a bit of a black art & good layout is essential. Feeds into an 8 ohm speaker after amplification. Volume control trimpot built in. Uses an LM358 & LM386 on a single sided PCB.

This kit connects to the phoneline and records the number dialled (tone dialling) and the duration of the call on a 2x16 LCD. It also accepts audio input from an microphone, tape recorder or magnetic pickup. Uses 68HC705K1 microcontroller. On-board phone & audio jacks.

Ion generator powered by 110-240V mains supply. It uses the standard Cockroft-Walton multiplier circuit - a ladder of diodes and capacitors to pump the output voltage up to the level required. Fuse built into the PCB. Uses ordinary needle work pins as the ion emitters. Neon indicator to show when the power is on. Reversing the 1N4007 diodes makes it a positive ion generator. The user must supply a suitable box for this project.

CAUTION: This is a high-voltage, mains supply project. The user must take extreme caution.

A very useful kit. Everybody has Infra Red transmitters at home - TV remote, video remote, CD remote, etc. Use ANY Infra Red remote to toggle this switch on or off. Relay output rated at 12VDC/10A or 240VAC/5A.

CAUTION: This is a high-voltage, mains supply project. The user must take extreme caution.

We developed a programmer for the P9 micro-controller used in our Codepad, Kit 53. We thought there was enough general interest to issue this programmer as a Kit. Top quality components are supplied. Space for 2 ZIF sockets. Double-sided PTH PCB.

Kit accepts an unregulated AC or DC input. The user supplies a standard 3 pin voltage regulator from 5 volts (using a 7805) to 24 volts (7824). The full range of possible regulators is: 7805, 7806, 7808, 1810, 7812, 7815, 7818 & 7824. Large heat-sink provided. PCB = 64mm x 40mm (2 1/2" x 1 1/2")

Make this general design 3 1/2 digit LED panel meter into your own voltage or current meter. Or customize it to measure input from a transducer. Full details given in the documentation. Separate display PCB.

This kit contains all the hard to get parts for a PIR motion detector. Includes the IR sensor, detector IC the KC778B and a PCB-mounted plastic Fresnel lens. Includes data on IC & Sensor.

Record as many messages as you can in this modern, non- volatile, combined audio processing & memory chip from Information Storage Devices (ISD25120). One button to START/PAUSE & a second button to RESET.

We are selling one type of module 4cm x 4cm, (1.6" x 1.6") with 127 p-n couples. When current passes through two different conductors, heat is produced in one and absorbed in the other. Peltier first described this in 1834. Modern semiconductor materials can make p-n junctions which produce large temperature differences. This 4cm x 4cm x 4mm thick module contains 127 p-n junctions connected electrically in series but thermally in parallel. Maximum temperature difference = 59 deg C at 30 deg C ambient with no heat load. Maximum ratings = 13.5V, 4.4A, 36W. Production code TEC1-12704.

Control the speed of any common DC motor rated up to 100V (5A). Operates on 5V to 15V. Uses NE556 to pulse-width modulate a high current switching power transistor, TIP122. In this way motor torque is maintained. Adjustable speed control. Box mounted.

This is a basic adjustable voltage power supply using the popular three pin regulator, LM317T. You can select any voltage between 1.5V and 30V using a potentiometer. The LM317T is rated at 1.5A so you must use a larger heat sink when drawing high currents.

One of the most popular electronic kits ever is an electronic dice. Now we have used a microcontroller to contain all the electronics. Only those items which cannot be put into software - like the display - are still in hardware. All the code is on floppy disk. PCB size 1.4"x2.6".

The code in Kit 69 is extended to roll two dice. PCB size 1.4"x2.6".

Control 8 relays using this IR Remote Control Unit. Over 20 meters in sunlight. Uses 2 high-powered IR LED's & latest IR detector/decoder from Kodenshi. Transmitter case, 8 miniature relays & all components provided. Uses paired encoder/decoder IC pair. Full instructions included. Four ranges set by jumpers.

NOTE: Nov 96. We have found that the latest batches of the SM5032B receiver decoder IC (date coded 9620 & 9630) do NOT work as the previous chips did. The problem has been traced to a change by the chip manufacturer. The two jumper-on option does not work. No jumpers on or only one jumper on still works OK. So this is now a 3 x 8 Channel IR Tx/Rx. The manufacturer says they will not be changing the chip at the moment.

Do you have an old PC lying around the house which absolutely no one wants? Then you can convert it into a dedicated controller. Communicate with the real world via the parallel printer port on your PC. Simply connect printer cable from computer to Centronics connector on relay board. There are 8 relays each capable of switching 12VDC/10A or 240VAC/5A. Each relay has an LED to indicate when it is operated. We provide two sets of complete, stand-alone software to control the relays: one works under DOS so you can write your own batch files to control individual relays, the other under Windows 3.1.

Three plug-in modules and a motherboard measure & display temperature (both C & F) and humidity, Counter & timer in seconds, and 4 AD conversions. Excellent practical as well as a learning tool.

3/2000. The 16C71 PIC has been discontinued. We are now using the 16C711 with the required slight code modification.

This kit is a fully assembled and tested miniature PIR module with only 3 connections: Power, Ground & Output. Rated for 5- 10VDC input power. Has 2 1/2" cable attached as shown in the photo. Uses RE200B PIR sensor. Output is an active high pulse of approx. 0.5 seconds and remains active as long as there is motion. Range up to 3 metres.

We provide 3 complete and separate Light/Dark LDR circuits each with a relay on-board all in the one kit. Each is a simple well tried circuit: one uses two transistors in a super-darlington setup, the second uses a LM741 op-amp while the third uses a Schmidt Trigger. Each board has a PCB-mounted switch to convert the circuit from light to dark switching and vice versa. There is nothing original in these circuits - they have been around for years. What we have done is bring three good timer circuits together all in the one Kit for you to build & experiment with.

Put in your own 78xx and 79xx 3-pin regulators (TO-220 type) to give fixed positive and negative voltage outputs which you want for your project. Supplied with 2 small heatsinks. Requires centre-tapped AC voltage source.

Dimensions = 78mm x 43mm

Many electronic projects use a low-voltage circuit to control the mains power supply eg. a touch switch, movement detectors, etc. In most cases the signal is brought out to a pad or terminal on the PCB. It is left up to the user to "use a suitable relay" to make the actual connection to the mains. Well this kit is the answer. It will take a +12V high or low going signal to switch a DPDT relay rated at 5A/240V. Both sides of the mains supply can be switched. A 5A fuse on one side is also included.

We provide 3 complete text book timer circuits all in the one kit. One is traditional 555 timer circuit, the second uses a 555 to pulse a counter while the third uses the discharge of a capacitor to time a period.

Turn on/off up to 4 relays over the telephone. Dial up your phone from anywhere in the world, input your pin number then turn on or off any of 4 relays. Use the relays to control any evices you have in your house or office. The pin number is set by 4 on-board BCD rotary switches. The circuit has the required telephone line protection circuitry built-in (but non approved.) The standard line impedance termination can be customised by the user for their own particular country if they want to get better impedance matching.

12V DC. 68HC705K1 controlled. All source code comes on floppy disk with the kit. The LED's in the photo are for testing to give a visual indication that the relays are working.

This stereo amplifier module uses the Samsung KA2209 8-pin IC. This is equivalent to the TDA2822. The circuit is the standard text-book circuit for this chip. No heat sink is required.

The TDA2009 is a class AB dual Hi-Fi Audio power amplifier monolithic IC designed for quality stereo applications. This is the standard data book application circuit using a minimum of external components. Each channel is capable of delivering 10 watts into 4 ohm speakers using a 24Vdc supply voltage. Dimensions = 79mm x 50mm

A simple, low cost stereo VU meter. Two LM3915 dot/bar display driver ICs are used to drive 2 rows of 10 LEDs (14 green, 6 red) in a moving bar display. Each row of LEDs spans a power range of 0-30 dB in ten 3-dB steps. This VU meter indicates "peak music power" when used with audio amplifiers. Ideal add-on for any of the amplifier kits. Dimensions = 65mm x 42mm.

A simple stereo 3 watt per channel amplifier based on the BA5406 power amplifier monolithic IC. Minimum component count. Runs on 12Vdc power supply. Good general purpose amplifier. Dimensions = 67mm x 38mm. Requires heatsink (supplied.)

Use the parallel port of your PC as a real world interface. It enables your PC to both monitor & control external events and devices. The world is a mixed analog & digital world. With the appropriate sensors the PC can monitor physical variables such as pressure, temperature, light intensity, weight, switch state, movement, relays, etc, process the information and then use the result to control physical devices such as motors, sirens, other relays, servo motors (up to 11) & two stepper motors. Includes 7 pages of documentation, schematic, heatsink, plastic box, and more!

This kit uses a Grey switch aka bit switch, to single step a unipolar tepper motor in either direction. Uses a PIC 16C54 plus UCN5804 stepper driver IC. PCB is 4 in square, single sided.

using the LM380. The IC solders directly to the PCB so no heatsink is required.

General preamplifier. It has a gain greater than 40dB which is enough for most applications. It can also take input from an electret microphone by adding one extra resistor (supplied in the kit.)

Uses MAX038. Comes in its own box with front & rear panel pieces. Coarse & fine tuning. Also TTL output. 2V p-p. Full instructions.

Using a PIC 16C71, a crystal, 8 resistors & 4 capacitors this kit will independently control up to 4 servo motors. We do not supply the potentiometers or servo motors. (We used a Futaba FP-S148 for out tests.) 5V DC power supply required. Full instructions provided.

As published in 11/99 Silicon Chip, Australia.

The electronic equivalent of a mechanical music box. It is activated by light falling on an LDR. It then plays a range of tunes. The kit can be placed anywhere you want to hear a tune when light shines on it; opening a cupboard or drawer, music box.

Make this general design 3 1/2 digit LED panel meter into your own voltage or current meter. Or customize it to measure input from a transducer. Full details given in the documentation. Separate display PCB.

8-Relay Module (mains rated - to 250VAC.) An extension of our Kit 74, PC controlled 8-Relay Board with safe & protected 250V switching relays and added features. It is in a plastic case, latched relay operation, 250V/12A certified relays switched by using Dinkle connectors (250V rated), and with 4 external inputs. Programmable. Comes with case and end panel pieces as shown in the photos. Uses serial port so it can be located over 100 yards from the PC. After programming the PC can be disconnected.

Drives any 5, 6 or 8 lead unipolar stepper motor. Based on the UCN5804 IC. All features of this IC (direction, on/off, pins 9 & 10) are brought out to SPDT PCB-mounted switches. Pulses from a 555 setup as an astable oscillator are used to rough position the motor. Switch to manual single-step mode for final positioning using a tact switch. 4 LED's give visual indication that step has been made. Three run modes supported. Full explanation.

A continuity tester is one of the most useful pieces of test equipment to have. It is used for testing the electrical continuity between two points. Our tester will "buzz" up to a specified resistance or less. Two on-board resistance ranges available. Full theory of operation given. The user may adjust the resistance ranges to suit his own requirements.

Simple circuit to generate square waves of approximately 1Hz 10Hz 100Hz 1KHz 10KHz & 100KHz.

Connects to the PC parallel port & will sample 0-2V or 0-20V at intervals from 1/hour to every 100uS. Copied (with permission) from Electronics Australia 8/96. PCB redesigned with PCB-mounted switches to be ALL CONTAINED IN AN EXTENDED D-SHELL CASE. No batteries needed.

Connects to the PC parallel port & will drive two stepper motors up to max. 3A each. All contained in an RS232, extended D-shell case. Software will accept 4 inputs from external switches. Software will also single step motors. Three run modes supported. All components supplied except the stepper motors.

Four on-board 100V, 3A diodes plus 2200uF/50V electrolytics to provide an unregulated power supply from a center-tapped transformer.

Uses 2 LM386N-1 for a stereo amplifier. Ideal for Walkman and other battery powered items. 4V - 12V DC.

Driver circuit for 8 ohm horn speakers. Based on the Zetex ZSD100 siren driver IC. 4V - 18V. 120dB of sound.

A continuity tester is one of the most useful pieces of test equipment to have. It is used for testing the electrical continuity between two points. Our tester will "buzz" up to a specified resistance or less. Two on-board resistance ranges available. Full theory of operation given. The user may adjust the resistance ranges to suit his own requirements.

The kit is driven from the Parallel Printer port of a PC using a straight thru M/F 25 pin cable. These are readily available.

There is no software Registration, as a programmed chip is supplied in the kit, and the PC driver software is free.

For volume programming and maximum flexibility the kit requires one on-board wide-slot 40-pin ZIF socket. The software tells you where to place the PIC you are programming. (Note some older designed PIC programmers available like the Warp-13 have 2 or even 3 (!) ZIF sockets on-board. Only one wide-slot 40 pin ZIF socket is necessary with PICALL.) The reason the 40 pin ZIF socket is not included is because these are manufactured in north America while the kit is packed in Hong Kong. Since most kits are sold in Europe & north America it is cheaper if you buy the socket locally.

It uses a MAX186 ADC. It all fits inside an extended D shell case which plugs onto the parallel DB25 connector of your PC. It has 8 analog inputs, 4 digital inputs & 4 digital outputs.

Uses LM34 or LM35 with a commercially available C&C LCD module.

To program 20-pin DIP - 90S1200, 90S2313, and 40-pin DIP - 90S4414, 90S8515. Programs at 9600 baud. Parallel mode. With the optional adaptor board you can now program AT90S4434 and AT90S8535. It will not program the 8-pin AVR devices (90S2323, 90S2343).

To program

• 89C1051, 89C2051 and 89C4051

• 89C51, 89LV51

• 89C52, 89LV52

• 89C55, 89LV55

• 89S8252, 89LS8252

• 89S53, 89LS53

• 87F51, 87F52 (otp) support added august, 2000

+/- 1.5V to 35V depending on input power source. On-board heatsink.

A double-sided board designed to eventually replace Kits 2 and 34.

The plastic tube is to put over the IR LED to restrict beam divergence. This is needed to prevent false triggering when the barrier is only a few yards wide.

Kit 133. KC7786. New 12VDC Movement detector Module with no cable.

Learn how to connect a 2x16 LCD to a PC parallel port. First this kit will show you how to write keystrokes from the PC keyboard to display on the LCD. It will show you how to process this data (rotate the string left and right.) All the code is provided. Second, there is an on-board DS1620 to measure temperature. The temperature is displayed in F or C. Just press a button to display either. With the DS1620 you may set breakpoints to turn a thermostat on/off. We provide all the code to do this. Once the DS1620 is programmed it may be removed and placed in another device for temperature control. Many web references are given.

Third in our series of low cost, single-sided PCBs using a micro-controller to replace a handful of ICs if built using traditional cmos ICs. (The previous two were kits 129 amd 154.) Has seven timing modes (all we could think of.)

These are the time delays possible:

• 1 - 255 seconds in steps of 1 second

• 10 - 2550 seconds (42min 30sec) in 10sec steps

• 1- 255 minutes in 1 minute steps

• 10 - 2550 minutes (42hr 30min) in 10 minute steps

Timing accuracy +/- 0.01%.

4-digit Timing Module with 6 types of firmware. This kit is the hardware platform for a number of different timing modules. The hardware is the same for each kit - the only change is the firmware programmed into an AT89C2051-24PC microcontroller. The kit itself comes with one firmware chip, a Programmable Down Timer from a maximum of 10,000 seconds. Other firmware chips are listed below.

PC Parallel port programmer for the 24xxx, I2C bus and 93xxx EEPROMS. 8 bit programming mode only. We use a 24C16 Software in the Christmas Tree Kit 103 so that was the main reason we did the kit. A 16 pin ZIF socket is used on-board. The top 8 pins are for the 24xxx; the bottom 8 are for the 93xxx SPI EEPROM's.

This Data Logger stores over 2,800 x 10 digit DTMF numbers. Records all buttons pressed during a call. Time and date recorded.

Here is a typical log report:

07-Aug-01 09:01:32,07-Aug-01 09:02:50,2748828821097231880838#02111111#1
07-Aug-01 09:12:07,07-Aug-01 09:14:10,23042250
07-Aug-01 09:37:51,07-Aug-01 09:37:55,
07-Aug-01 09:54:10,07-Aug-01 09:54:28,
07-Aug-01 10:12:55,07-Aug-01 10:13:36,23042250
07-Aug-01 10:27:26,07-Aug-01 10:27:47,
07-Aug-01 10:40:38,07-Aug-01 10:41:18,
07-Aug-01 10:45:51,07-Aug-01 10:46:22,230422501
07-Aug-01 10:49:07,07-Aug-01 10:49:14,88888888


Lines with no numbers pressed are incoming calls.