[MOC] Portable radio receiver

[Jurss]

Yesterday had inspiration to build something, and idea was about portable radio with some functions, of course as for technic forum.I don't have any sound brick, so it doesn't have any sound, but You can see some kind of fake speaker behind grill.

Battery tray at the back

Antenna rised

Some look on internals

For "tuning" wormgear is used. Tuning is done by upper knob.

With lower knob it is possible to "switch on" radio, which just lits up two light bricks. Position is simply fixed with those black balls locking on those black connectors.

Because of those worm gears in way of light, illumination has specific pattern. Maybe will remake so, that light is reflected from some white panel, as from those light bricks it is pretty directional.

As all wormgears together had pretty big play, almost half stud, but not that half stud, to make legal build used rubber as spacer, to fill gap. Without this, at some point that "pointer" could just stuck between two wormgears.

Handle also is usable, as it is reinforced with internal tube.

Final note -  it weights 272g, but I don't have intention yet to participate in contest, and weight was not a goal. When I started, I even didn't knew, that contest has been anounced.

Edited December 28, 2025 by Jurss

[allanp]

I wonder if you could incorporate an ungeared Lego motor to make a working speaker, something like this?

Maybe do it as shown. But I also wonder if it would work better with the motor turned sideways and connect the speaker dish with an offset fixed crank like connection?

 

Edited December 28, 2025 by allanp

[Paul B Technic]

That is very cool, thanks for sharing it.

[Jurss]

11 hours ago, allanp said:

But I also wonder if it would work better with the motor turned sideways and connect the speaker dish with an offset fixed crank like connection?

Theoretically that could work. I just don't have there space anymore for that. Or I could get rid of battery tray. Or relocate it to side. I just need then to sacrifice some lego cable for this.

Edited December 29, 2025 by Jurss