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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.


High-powered, portable, twin-speaker loud hailer. One IC produces 5 watts output.
ELEMENTARY ELECTRONICS Sep-Oct 1969 (v.9#1) pg. 31

Simple circuit for a loudhailer powered by a 6-volt battery.
ELEMENTARY ELECTRONICS May-Jun 1974 (v.14#3) pg. 66

Build a portable electronic megaphone. Uses the latest in low-power digital amplifiers.
ELEMENTARY ELECTRONICS Mar-Apr 1975 (v.15#2) pg. 59

Bull horn circuit uses the 386 low-voltage amplifier and 377 dual amplifier found in inexpensive audio systems.
HANDS-ON ELECTRONICS May 1987 (v.4#5) pg. 96

How to build a loudhailer (electronic megaphone) with a range of 1,000 ft. Horn speaker also collects sounds and feeds them to a built-in amplifier to catch replies. Pushbutton on microphone has push-to-talk, release-to-listen feature. Hailer also has built-in fog horn.
MECHANIX ILLUSTRATED #538 Mar 1973 (v.69) pg. 104

Simple transistor amplifier circuit can be used as a power megaphone.
POPULAR ELECTRONICS [1] Jun 1965 (v.22#6) pg. 73

A single power transistor in a common-emitter arrangement supplies driving energy for power megaphone circuit.
POPULAR ELECTRONICS [1] Nov 1966 (v.25#5) pg. 83

Circuit for a bull-mike public address system. Est. cost: $8.
POPULAR ELECTRONICS [1] May 1968 (v.28#5) pg. 68

Mini-megaphone circuit combines an electret microphone, low-voltage audio-power amplifier, and a horn speaker.
POPULAR ELECTRONICS [2] May 1994 (v.11#5) pg. 80, 90

Power megaphone or bullhorn.
POPULAR SCIENCE Apr 1964 (v.184#4) pg. 134

Electronic loudhailer and bull horn with built-in siren. Powered by four C batteries. Est. cost: $25.
RADIO-TV EXPERIMENTER #772 Feb-Mar 1966 (v.20#1) pg. 37