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 Schematics  >> 

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Dual Light PIC Switch
This is a lamp timer capable of operating two separate relay switches. Outputs can be in three (or restricted to two) states: OFF, delayed ON and constant ON. Delayed ON mode is indicated by the LEDs. The source code is easily customizable for your needs: set your desired delay time or disable constant ON state.

Electronic Lock
This is my electronic combination lock to use with an outdoor gate. The functionality is implemented in software. It turns on a relay (usually to open a door) for a few seconds if someone enters the valid code. This relay can operate a power-to-open type electric strike with a shorting contact or a power-to-hold type electromagnetic lock with a breaking contact (we need the relay because these locks usually work with AC, not DC). The code can be changed any time after entering the current code.

EPROM Programmer Mk2
Back in 1995 I designed a Mk2 EPROM Programmer, but EA didn't want to publish it. I'm making all of the details available here for those that wish to make it themselves. The schematics, PCB, control program, and PLD files are available here for general interest only, they are still copyrighted to me. This design is NOT in the public domain.

Garden Timer with Remote control
Few years ago we control the lights in the garden with a automatic-timer-switch, very nice but when the evening gets longer or shorter we had to adapt the timer each week. In that time I came in contact with programming microprocessors so my first project was born. The first garden timer was a simple 1 output. The timing was controlled by the PIC and every month I had to change the minutes. So back to the table and design the second garden timer able to control 3 relays - left, mid and right side of the garden. It provided also 4 modes: always off always on from dusk to dawn from dusk to timer and the timing was dedicated to a RTC DS1307.

Generator of exact pulses
Circuit is very simple. The generator uses a PIC12F629 microcontroller with clock frequency set by an external RC. Output frequency can be set trimmer P1 in the range of about 2 to 170 Hz. Oscillator frequency can be adjusted if you change C1 capacitance. Pulses are generated with a period of 200 Tcy. All pulses are of equal length. Output frequency is 800 times lower than the frequency of the oscillator.

IR RC5 Remote Control Transmitter
All remote controlled projects from this site can be controlled with remote controls which use the RC5 protocol, like the TV-remotes from Philips. When all buttons from such a remote are in use then you could make a remote control by yourself. Your own build remote control with only one button or maybe you want to build a remote with more then hundred buttons. It is possible, however, you need the PIC Basic compiler from Crownhill seeing that everyone has his own wishes and you have to fill in which button sends which RC5 code.

JDM PIC Programmer
Allows to program PIC16F84, PIC16F628, PIC16F877, etc..

JDM Programmer Modification
The JDM (or Ludipipo) seems to be among the most popular PIC programmers used - and rightly so: it is simple, cheap and easy to build, can be run with the free and excellent IC Prog software by Bonny Gijzen, and will program pretty much any PIC microcontroller on the market. However, an issue has arisen lately with some of the new PIC's, eg PIC12F675, 12F629, and some others with an internal oscillator. When these chips are programmed the first time, everything goes fine. However, if you later try to read or re-write to them, they read as blank and cannot be written to. The problem only occurs when the PIC has been programmed for INTOSC and MCLR_OFF, but even in this situation sometimes it will re-program OK - there seems to be some other dependence on the program which has been loaded as well.

JDM2 PIC 18F Programmer
This is a simple serial based JDM2 PIC Programmer for programming PIC18F chips. The Programmer is powered by the RS-232 port and it works with RS-232 levels at only < 8.6V. It programs PIC12C5XX, 12C67X, 24CXX, 16C55X, 16C61, 16C62X, 16C71, 16C71X, 16C8X, 16F8X and ISO-CARD's with ASF. The high Vpp is obtained by using negative voltage to drive the chip. The voltage is stabilized with zener diodes. They do not need voltage drop as if a voltage regulator, or has much offset current. This makes it possible to use extra low input voltage. Transistor driver guarantee output level > 3V. The programmer is supported by PICPgm and WinPic programming software.

LC Meter Based on the AVR Microcontroller
Calculates and displays L and C from oscillation frequency using reference components. This instrument requires two precision components: A precision capacitor and a precision inductor. You only need to start with one precision component, either the reference capacitor or the reference inductor, and using this meter, you can select or adjust the other precision component. In my case, I used a pretty high accuracy BK Precision inductance/capacitance meter and sorted through piles of inductors and capacitors to find those that had the lowest error. I then used those parts, a 1 millihenry inductor and a 0.01 microfarad capacitor, in this meter. The basis of this project is several similar projects on the world wide web and some magazine articles before the world wide web was a common means of information interchange. Unfortunately, I am not able to determine the originator(s) of the concept, but I suspect that it is as old as radio. Another project on my web site, LC Determination by Resonant Frequency Measurement, measures the resonant frequency of an L/C circuit, but the hardware stops at the frequency measurement. It does not proceed to calculate the unknown inductance or capacitance.

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Accurate LC Meter Capacitance Inductance Meter with 16F628 and LCD
Volt Ampere Meter with 16F876 Microcontroller and LCD display
Accurate LC Meter

Build your own Accurate LC Meter (Capacitance Inductance Meter) and start making your own coils and inductors. This LC Meter allows to measure incredibly small inductances making it perfect tool for making all types of RF coils and inductors. LC Meter can measure inductances starting from 10nH - 1000nH, 1uH - 1000uH, 1mH - 100mH and capacitances from 0.1pF up to 900nF. The circuit includes an auto ranging as well as reset switch and produces very accurate and stable readings.
PIC Volt Ampere Meter

Volt Ampere Meter measures voltage of 0-70V or 0-500V with 100mV resolution and current consumption 0-10A or more with 10mA resolution. The meter is a perfect addition to any power supply, battery chargers and other electronic projects where voltage and current must be monitored. The meter uses PIC16F876A microcontroller with 16x2 backlighted LCD.

50MHz 60MHz Frequency Meter / Counter with 16F628 & LCD
1Hz - 2MHz XR2206 Function Generator
60MHz Frequency Meter / Counter

Frequency Meter / Counter measures frequency from 10Hz to 60MHz with 10Hz resolution. It is a very useful bench test equipment for testing and finding out the frequency of various devices with unknown frequency such as oscillators, radio receivers, transmitters, function generators, crystals, etc.
1Hz - 2MHz XR2206 Function Generator

1Hz - 2MHz XR2206 Function Generator produces high quality sine, square and triangle waveforms of high-stability and accuracy. The output waveforms can be both amplitude and frequency modulated. Output of 1Hz - 2MHz XR2206 Function Generator can be connected directly to 60MHz Counter for setting precise frequency output.

BA1404 HI-FI Stereo FM Transmitter
USB IO Board PIC18F2455 / PIC18F2550
BA1404 HI-FI Stereo FM Transmitter

Be "On Air" with your own radio station! BA1404 HI-FI Stereo FM Transmitter broadcasts high quality stereo signal in 88MHz - 108MHz FM band. It can be connected to any type of stereo audio source such as iPod, Computer, Laptop, CD Player, Walkman, Television, Satellite Receiver, Tape Deck or other stereo system to transmit stereo sound with excellent clarity throughout your home, office, yard or camp ground.
USB IO Board

USB IO Board is a tiny spectacular little development board / parallel port replacement featuring PIC18F2455/PIC18F2550 microcontroller. USB IO Board is compatible with Windows / Mac OSX / Linux computers. When attached to Windows IO board will show up as RS232 COM port. You can control 16 individual microcontroller I/O pins by sending simple serial commands. USB IO Board is self-powered by USB port and can provide up to 500mA for electronic projects. USB IO Board is breadboard compatible.

ESR Meter / Transistor Tester Kit
Audiophile Headphone Amplifier Kit
ESR Meter / Capacitance / Inductance / Transistor Tester Kit

ESR Meter kit is an amazing multimeter that measures ESR values, capacitance (100pF - 20,000uF), inductance, resistance (0.1 Ohm - 20 MOhm), tests many different types of transistors such as NPN, PNP, FETs, MOSFETs, Thyristors, SCRs, Triacs and many types of diodes. It also analyzes transistor's characteristics such as voltage and gain. It is an irreplaceable tool for troubleshooting and repairing electronic equipment by determining performance and health of electrolytic capacitors. Unlike other ESR Meters that only measure ESR value this one measures capacitor's ESR value as well as its capacitance all at the same time.
Audiophile Headphone Amplifier Kit

Audiophile headphone amplifier kit includes high quality audio grade components such as Burr Brown OPA2134 opamp, ALPS volume control potentiometer, Ti TLE2426 rail splitter, Ultra-Low ESR 220uF/25V Panasonic FM filtering capacitors, High quality WIMA input and decoupling capacitors and Vishay Dale resistors. 8-DIP machined IC socket allows to swap OPA2134 with many other dual opamp chips such as OPA2132, OPA2227, OPA2228, dual OPA132, OPA627, etc. Headphone amplifier is small enough to fit in Altoids tin box, and thanks to low power consumption may be supplied from a single 9V battery.

Arduino Prototype Kit
RF Remote Control 433MHz Four Channel
Arduino Prototype Kit

Arduino Prototype is a spectacular development board fully compatible with Arduino Pro. It's breadboard compatible so it can be plugged into a breadboard for quick prototyping, and it has VCC & GND power pins available on both sides of PCB. It's small, power efficient, yet customizable through onboard 2 x 7 perfboard that can be used for connecting various sensors and connectors. Arduino Prototype uses all standard through-hole components for easy construction, two of which are hidden underneath IC socket. Board features 28-PIN DIP IC socket, user replaceable ATmega328 microcontroller flashed with Arduino bootloader, 16MHz crystal resonator and a reset switch. It has 14 digital input/output pins (0-13) of which 6 can be used as PWM outputs and 6 analog inputs (A0-A5). Arduino sketches are uploaded through any USB-Serial adapter connected to 6-PIN ICSP female header. Board is supplied by 2-5V voltage and may be powered by a battery such as Lithium Ion cell, two AA cells, external power supply or USB power adapter.
200m 4-Channel 433MHz Wireless RF Remote Control

Having the ability to control various appliances inside or outside of your house wirelessly is a huge convenience, and can make your life much easier and fun. RF remote control provides long range of up to 200m / 650ft and can find many uses for controlling different devices, and it works even through the walls. You can control lights, fans, AC system, computer, printer, amplifier, robots, garage door, security systems, motor-driven curtains, motorized window blinds, door locks, sprinklers, motorized projection screens and anything else you can think of.
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