Detailed entries for one subject from the INDEX TO HOW TO DO IT INFORMATION.
Click on a see also (sa) or tracing (xx) to view detailed entries about a related subject.
The entries are in alphabetical order by magazine name and then in chronological sequence.
To obtain a copy of any magazine article contact your local public library or the publisher.

Circuits for a (1) proximity detector and (2) light sensor incorporate a light-to-voltage converter chip.
CQ. THE RADIO AMATEUR'S JOURNAL Sep 1993 (v.49#9) pg. 86

Ultrasonic burglar alarm can also be used as a proximity detector or a fire alarm. Works up to 20 feet.
ELECTRONICS ILLUSTRATED Jan 1969 (v.12#1) pg. 85

Flashing red light controlled by a proximity switch warns people not to open a door.
ELEMENTARY ELECTRONICS Jul-Aug 1969 (v.8#3) pg. 65

Easy-to-build proximity sensor adds to the detection ability of your existing burglar alarm. Use with any system that uses a normally closed sensor circuit. Protects any metal object that can be isolated from earth ground.
ELEMENTARY ELECTRONICS Nov-Dec 1974 (v.14#6) pg. 77

Circuit for a sensitive proximity-alarm incorporates a 4049 CMOS hex inverting buffer.
HANDS-ON ELECTRONICS Nov 1986 (v.3#6) pg. 92

Proximity detector circuits turn switches on and off whenever a person comes within their electric field.
HANDS-ON ELECTRONICS Jan 1987 (v.4#1) pg. 40

Proximity alarm circuit is used as part of a counter to monitor the number of people using a door.
HANDS-ON ELECTRONICS Mar 1987 (v.4#3) pg. 26

Diagram of a simple transistorized capacitance relay that can be operated by bringing a person's hand close to a plate.
POPULAR ELECTRONICS [1] Mar 1968 (v.28#3) pg. 77

Proximity relay detects movement up to 3 ft. away. Est. cost: $19.
POPULAR ELECTRONICS [1] Jun 1968 (v.28#6) pg. 27

Proximity switch circuit utilizes a power hexFET. Sensitivity can be varied.
POPULAR ELECTRONICS [2] May 1989 (v.6#5) pg. 85

Proximity switch circuit is triggered by a reflected infrared (IR) signal. Includes an optocoupler-based Triac-driver circuit which can be added to control a small AC motor.
POPULAR ELECTRONICS [2] Nov 1990 (v.7#11) pg. 75

Proximity detector circuit incorporates a 567 tone decoder.
POPULAR ELECTRONICS [2] May 1991 (v.8#5) pg. 74

Using a single special-purpose IC (the ULN2429A fluid detector) in as many applications as possible. (1) Low-level liquid level detector. (2) High-level liquid level detector. (3) Touch-activated switch. (4) Proximity sensor. (5) Ultrasonic pest repeller. (6) Variable square-wave generator. (7) Code-practice oscillator. (8) Alarm circuit. (9) Light beam circuit (LED-emitter / phototransistor-sensor circuit).
POPULAR ELECTRONICS [2] Jun 1994 (v.11#6) pg. 76

More ultrasonic circuits. (1) CW (Morse code) transmitter. (2) Motion detector. (3) Proximity detector.
POPULAR ELECTRONICS [2] Jan 1995 (v.12#1) pg. 71
Correction POPULAR ELECTRONICS [2] Apr 1995 (v.12#4) pg. 4

Proximity switch controls AC circuit whenever a hand (or other part of your body) is passed near an insulated touchplate.
RADIO-ELECTRONICS May 1984 (v.55#5) pg. 38
Correction RADIO-ELECTRONICS Jul 1984 (v.55#7) pg. 14

TRIAC capacitance switch will turn off a lamp or other load when an external body comes near an insulated metal plate. Est. cost: $20.
RADIO-TV EXPERIMENTER #814 Dec 1966-Jan 1967 (v.21#3) pg. 49

Copyright © by Norman Lathrop Enterprises. All Rights Reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means (electronic, mechanical, print photocopying, recording or otherwise) without the prior expressed permission of Norman Lathrop Enterprises, except as permitted by law.