“This device was created for pleasure and inspiration for anyone who would like to make a simple voice recorder for their children to play, or as a decoration, or use in Geocaching or in escape rooms. There are many possibilities. So let’s get to it.
Let’s start with the toy concept. The device must include a microphone, loudspeaker, recording module, a switch and control buttons, and some decorative elements. All in a battery-powered box. I decided to use the ISD 1820 module, cheap and easy to find on ebay. The 9 volt battery needs an intermediate circuit, which will be a simple dc-dc converter to 5V. The second figure outlines two variants of the arrangement of individual components and parts.
Parts:
1x ISD1820
1x 9 Volt battery
2x Push button
1x Toggle switch
1x DC-DC converter
9 Volt battery clip
1x 47ohm resistor
1x 470k ohm resistor
1x 2n3904 npn transistor
1x 5V Light bulb
24 Awg stranded wires
Heat shrink tubes
Soldering Iron
Soldering solder
Cutting pliers
Needle nose pliers
Cutting pliers
Acrylic paints (silver, brass / copper)
Screwdriver
Multimeter”