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• HONEYBEE COUNTER
  I designed a circuit similar to this one a long time ago to help a beekeeper count the number of bees going into or out of a hive. The low power circuit uses a slotted opto-sensor to detect the passing bees. The circuit advances an electronic counting module whenever a honeybee passes through the sensor. The device only counts the number of bees going through the sensor. A different circuit would be needed to count the number of bees only going out or only coming into the hive.

• LONG PERIOD COMPUTER WATCH DOG TIMER
  This circuit uses a simple 4060 IC oscillator/timer which is reset periodically by a computer. Should the computer fail to send a pulse, the output changes state. The time can easily be set from seconds to hours.

Generation of 1-Sec. Pulses Spaced 5-Sec. Apart:  (electronic Circuit / Schematic added 10/04)

Get six quick tips to make more accurate frequency measurements:  Agilent Application Note   (app note added 6/06)

Giant Money Counter (PIC16F876):  (circuit / schematic design added 6/06)

Ground Rules for High Speed Circuits:  AN-214 Analog Devices Application Notes  (app note added 2/06)  Layout and Wiring Are Critical in Video Converter Circuits.

Headlights Timer:  Pushbutton activated Very simple circuitry (added 3/05)

High Frequency Applications: PI6C2520:  Pericom Semiconductor Application Note # 039 (app note added 02/05)

High Speed BUS LVDS Clock DistributionUsing the DS92CK16 Clock Distribution Device:  National Semiconductor Application Note   (app note added 2/06)

High Speed Clock Sources and Their Effect on Electromagnetic Compatibility:  National Semiconductor Application Note   (app note added 2/06)

How to De-Bug and Design DDR Memory Modules:  Pericom Semiconductor Application Note # 068 (app note added 02/05)

Infrared Remote Control Timer:  (electronic Circuit / Schematic added 10/04)

Interface single-ended signal to DDR devices:  Pericom Semiconductor Application Note # 056 (app note added 02/05)

Jitter Measurement Techniques:  Pericom Semiconductor Application Brief # 036 (app note added 02/05)

Jogging timer:  3V Battery Powered Beeps after a fixed number of minutes (added 9/04)

Keys to Longer Life for CMOS:  AN-349 Analog Devices Application Notes  (app note added 2/06)  Here's How CMOS Can be Protected Against Abuse

Layout Guidelines PI6C110/PI6C110E:  Pericom Semiconductor Application Brief # 027 (app note added 02/05)

LB-38: Wide Range Timer:  National Semiconductor Application Note   (app note added 2/06)

LED Counter:  This circuit is the 12-bit binary counter which used 4040B. The number of the pulses of the input can be confirmed by seeing it with the eyes by putting the light-emitting diode to the output of the counter.  It is the function only of it but it is useful. Because it is the 12 bits, the highest rank counter is divided to 1/4096. Because it is, in the highest rank, the signal of 4KHz can be seen in the about 500-millisecond blink. At the input circuit, it is protecting the counter IC from the excessive input voltage with the resistor and the Zener diode.  (app note added 4/05)