Specifications

2000
Contents
SEPTEMBER 2000
CONSTRUCTION PROJECTS
1) DISPLAY SCHEMES FOR INDIAN LANGUAGESPART II (Hardware and Software) -------------------- 123
2) DIGITAL CODE LOCK ----------------------------------------------------------------------------------------------------- 133
CIRCUIT IDEAS
1) BINARY TO DOTMATRIX DISPLAY DECODER/DRIVER ----------------------------------------------------------- 137
2) AUTOMATIC SPEED-CONTROLLER FOR FANS AND COOLERS ------------------------------------------------ 139
3) BLOWN FUSE INDICATOR ---------------------------------------------------------------------------------------------- 140
4) OVER-/UNDER-VOLTAGE CUT-OFF WITH ON-TIME DELAY ----------------------------------------------------- 140
5) ONE BUTTON FOR STEP, RUN, AND HALT COMMANDS ------------------------------------------------------- 142
OCTOBER 2000
CONSTRUCTION PROJECTS
1) MOSFET-BASED 50Hz SINEWAVE UPS-CUM-EPS ---------------------------------------------------------------- 143
2) R-2R D/A CONVERTER-BASED FUNCTION GENERATOR USING PIC16C84 MICROCONTROLLER ---- 150
CIRCUIT IDEAS
1) SIMPLE SWITCH MODE POWER SUPPLY --------------------------------------------------------------------------- 155
2) TOILET INDICATOR ------------------------------------------------------------------------------------------------------- 155
3) FEATHER-TOUCH SWITCHES FOR MAINS -------------------------------------------------------------------------- 156
4) DIGITAL FAN REGULATOR ---------------------------------------------------------------------------------------------- 157
5) TELEPHONE RINGER USING TIMER ICS ----------------------------------------------------------------------------- 159
NOVEMBER 2000
CONSTRUCTION PROJECTS
1) PC-TO-PC COMMUNICATION USING INFRARED/LASER BEAM ----------------------------------------------- 160
2) MULTI-EFFECT CHASER LIGHTS USING 8051 MICROCONTROLLER ----------------------------------------- 166
CIRCUIT IDEAS
1) AUTOMATIC BATTERY CHARGER ------------------------------------------------------------------------------------- 170
2) TEMPERATURE MEASUREMENT INSTRUMENT ------------------------------------------------------------------- 171
3) VOICE BELL ----------------------------------------------------------------------------------------------------------------- 172
4) MOVING CURTAIN DISPLAY ------------------------------------------------------------------------------------------- 173
5) PROXIMITY DETECTOR -------------------------------------------------------------------------------------------------- 174
DECEMBER 2000
CONSTRUCTION PROJECTS
1) ELECTRONIC BELL SYSTEM --------------------------------------------------------------------------------------------- 175
2) SIMPLE TELEPHONE RECORDING/ANSWERING MACHINE ---------------------------------------------------- 179
CIRCUIT IDEAS
1) MULTICHANNEL CONTROL USING SOFT SWITCHES ------------------------------------------------------------ 183
2) AN EXCLUSIVE SINEWAVE GENERATOR ---------------------------------------------------------------------------- 184
3) TTL THREE-STATE LOGIC PROBE -------------------------------------------------------------------------------------- 185
4) AM DSB TRANSMITTER FOR HAMS ---------------------------------------------------------------------------------- 185
5) GROUND CONDUCTIVITY MEASUREMENT ------------------------------------------------------------------------ 186
6) STEPPER MOTOR CONTROL VIA PARALLEL PORT ---------------------------------------------------------------- 187