Flasher

This "flasher" is not an exhibitionist, as you might think from the name.

It's actually a very simple beambot design, one that just flashes a LED.

The tricky bit is getting enough voltage to light up the diode. If you want to power your bot with solar cells or an AA battery, you will need a step-up converter.

Circuitry

There's many such converters, a quick Google search will give you some ideas.

Google search example

Ok, maybe try something like "flasher beambot" instead =D

Here's some of the circuits I've tried:

Coil-less 1.5V LED flasher

This is the circuit I used in my "flasher" beambots.

Here's a schematic (source):

Schematic 1

It's OK, but needs a bit higher voltage to work right. 1.5V or slightly more is perfect.

Solar garden-light circuit

This schematic is from a solar-powered garden light.

I haven't tried to rebuild it yet, but it should be a good option for powering beambots in general.

It certainly provides enough voltage and current to light up a white LED.

Adding a parallel capacitor to the output might be a good idea, since there's going to be some noise from the coils. If you just send it to a motor, you shouldn't need to worry about this.

Schematic

I've disassembled it and traced the connections on the PCB. Please excuse my drawing skills ^^

Schematic 2

Here's values of the parts:

Part Value
R1 10k
R2 100k
R3 5k1
C1 100 pF
L1 150 μH
L2 410 μH
T1, T2 S8050D
D1 1N5819

The solar cell should give around 2V. The garden light used 4 cells in series, those can give about 0.5V each, depending on quality.

I believe the accumulator was a NiMH one, those are rated 1.2V. Any 1.5V one should work just fine, too. A large capacitor would also work, to some extent.

Glow in dark

The garden light harvests solar energy during day, and lights up at night.

If you take out T2 (and the attached resistors R2 and R1), the "light in dark" feature should be disabled and it'll work always.

Flasher builds

One of my flashers is shown in the header photo.

Here's my other builds:

Found an error, have a question, wanna chat? Tweet at me @MightyPork