Feltronics Radio

The first radio created with Feltronics, while functional, was a bit complicated. And as can be seen in photographs of our early days, we did not have a consistent product. All of the pieces were cut by hand, and some individuals did a slightly better job. But it worked! A working radio transmitter in felt!

Felt circuit schematic symbols on whiteboard in the form of a radio circuit
Early feltronics circuit with a mix of hand-cut and laser cut parts.

The second iteration of the Feltronics Radio was a work of simplicity. Working with large fuzzy components is great for the the whiteboard in front of a large classroom. But whiteboards are still only so big and complex circuits lead to very busy schematics that also happen to be difficult to comprehend. The answer was to boil a radio down to it’s most essential components. Thus the 5 component transistor radio transmitter was born… in felt. This particular radio puts out a 1Mhz signal. There is a bit of drift as is to be expected in such a simple radio, but that just makes it easier to pick up on a receiver (no phase lock loop radios please). Kids can understand what each of the 5 components do individually and can even work out how then affect each other. Kids literally have the “I know kung fu” moment, and never look back.

Felt circuit schematic symbols on in the form of a radio circuit connected to oscilloscope showing generated 1Mhz waveform
A much simplified radio… with proof of life!

First Radio

Child holding circuit breadboard with very few wires and an earpiece

The the magic they bring and the powerful way they forever changed the world, radios don’t have to be that complicated.

Joshua Made his first radio with some wire, and earphone, and a diode. He jammed one end of the wire into the ground and a breadboard. Connected that to an earphone which was in turn connected to a diode. The diode was connected to the other side of the earphone and to one more piece of wire thrown high up into a tree… the antenna. That was it!

Radio was brought to life. He could immediately hear a trumpet playing music… on the radio. No tuning required. Actually no tuning is even possible with this simple design, you hear the loudest, strongest station broadcasting. But it’s so simple! This magical arrangement of uncomplicated stuff can pull electromagnetic waves out of the thin and turn them into music.

But the best part was that immediately after hearing sound from no where, Joshua thought of nothing other than to share it with his sister.

Boy and girl crouch low to ground to listen to very primitive radio
Upon hearing sound from the first radio he ever made, Joshua shares it with his sister