Solar Moving Tail Wagging Dog,. Good potential for using parts - Page 1
Forum section: electronics / projects

author: RJSV
author_rank: Super Contributor
timestamp: June 08, 2024, 08:05:13 pm
content: Bought this Doggy Birthday card, a SOLAR job, likely using same or similar parts to the Garden lights.I wanted to post picture before tearing the paper housing.Looks like has a fast pendulum like wag and the solar cells are tiny, like1 cm by 20, or 2 cells, at 1 cm by 10 cm.Haven't seen this cheaper contraption, today was in grocery store.

author: RJSV
author_rank: Super Contributor
timestamp: June 08, 2024, 08:55:02 pm
content: Using parts, (like shown in photo),;This can make a good, fast project for a nephew...or grand-niece. There aren't even any voltages to speak of,....course maybe 1.5 volts from the little calculator type solar cell.No dangerous voltage, and simple to understand, I could do the package with a decent box and so forth.Coil seen, at bottom of the tail thingy.Plus 2 magnets, stationary in the stationary.

author: RJSV
author_rank: Super Contributor
timestamp: June 09, 2024, 11:09:32 pm
content: I'll need to provide a magnified view, but the Motion Greeting Card has a stiff foam core, with thick paper glued to the foam core, as front and back faces.Imbedded into the core, is a plastic square frame, for mounting the pivoting pendulum.I didn't realize, but by putting the coil portion of the back and forth lever, the whole moving portion is then very light...oscillating gently at about 2 hz, or two times per second pendulum.Flat magnets are stuck to card, in front of the oscillating coils,...and likely the coil is simply with the two fine wires, loosely, thus avoiding needing a brush or commutator.The circuit is, simply powered directly from solar cell, (no battery), plus there is a small,47 ufd. type power input cap.And a small epoxy dab over some circuit, no switching or loudspeaker output.Just the two pwr wires coming in, and two wires to drive the coil for oscillating lever.A project box, could start with just those (4), connections, via. some regular banana jacks.Then add things from there, to make it interesting to, say, an 8 year old.(Hopefully old enough to not be swallowing things, small parts or batteries!).

author: RJSV
author_rank: Super Contributor
timestamp: June 10, 2024, 05:54:26 am
content: First off, a closer look at the oscillating tail, which has a quite large looking coil, seems like too much in windings.Anyway,I figured 4 mm thick coil of thin magnet wire, as approx 12 wires thick, with each representing 40 turns, or so. That comes to about 480 turns, of the very thin, red wire.But the whole oscillating thing, is mostly stiff foam, along with whatever the coil weight is.

author: RJSV
author_rank: Super Contributor
timestamp: June 10, 2024, 06:00:16 am
content: In this second close-up shows the fairly elaborate plastic frame used, with the oscillating vane thing shown, in cut away.

author: RJSV
author_rank: Super Contributor
timestamp: June 10, 2024, 11:39:13 pm
content: So the voltage from the 2 solar cells is about 2.7 volts. That's indoors in bright room, and out under sunlight it goes to 3 V.So I don't know if those two cells are in parallel, mainly due to caution taking the layers of glued foam and the wires being very delicate!My approach, there, is using fine grade sandpaper, (220?), and basically rubbing off insulation. Then wrap couple turns tight around a tiny piece of solid hook-up wire, and solder the delicate wire.The red coated magnet wire is even more wispy, and in this toy mechanism can't hardly see it.