| 17-JUN-1987 Red box info HOW TO BUILD AND USE A RED BOX...... =->= == ---------------------- THE RED BOX BASICALLY SIMULATES THE SOUND OF COINS BEING DROPPED INTO THE COIN SLOT OF A PAY TELEPHONE. A PAY TELEPHONE GENERATES A BURST OF TWO MIXED FREQUENC IES, 1700 HZ AND 2200 HZ, FOR A SPECIFIC TIME INTERVAL TO DENOTE A NICKLR, DIME, OR QUARTER. A NICKLE IS 1700 HZ +2200 HZ FOR 66 MILLISECONDS. A DIME IS 1700 HZ + 2200 HZ FOR 66 MILLI. SECS. ON, 66 MS. OFF , THEN 66 MS ON AGAIN. FINALLY, A QUARTER IS 1700 HZ+2200 HZ FOR 33,MS ON, 33 MS, OFF, CONTINUOSLY REPEATING FOR 5 TIMES. WHEN USING A RED BOX ON A PAY PHONE, FIRST DEPOSIT A REAL NICKLE (BECAUSE T HEY CAN TELL IF THE FIRST ONE IS A REAL ONE OR JUST A TONE), THEN USE THE TONE B URST. YOU CAN BUILD THE CIRCUIT TO GENERATE A NICKLE TONE, THEN RECORD IT AND PL AY IT INTO THE PAY PHONE WITH A WALKMAN CASETTE PLAYER. TO GET THE MAP, SEND \$2 DOLLARS TO MASTER WORLD 1609 S. BENTLEY AVE LOS ANGELES, CALIFORNIA 90025 THE MAP HAS MANY FIGURES THAT THE COMPUTER CANNOT PRODUCE. IF YOU HAVE THE MAP , HERE ARE SOME TIPS ADJUST R1 TO GET 2200 HZ AT POINT A ADJUST R2 " " 1700 HZ " " B PRESS SWITCH FOR 66 MS ON AT SPEAKER THIS SIMULATES A NICKLE THE 555 TIMER-> 66MS TIMER THE 556 DUAL TIMER->2200HZ+1700HZ GENERATOR 741->TIMER OP AMP BUFFER FOR SPEAKER SO REMEMBER IF YOU DON'T HAVE THE MAP SEND TWO DOLLARS TO THE ADDRESS UP ABOVE --- The World of Cryton (UK) --- +44 4 584 7608