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Idea re 115V timed stepping or rotary switch

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karl_ottawa

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I'm sure this exists in different forms but I haven't found an easy, economical way of doing it yet.
What I'd like to do is have some type of timed rotoray switch system that would turn on a different outlet for each step. I figure I would need 3 to 5 outlets. Each of these outlets would have a set of christmas lights plugged in. So that you could make a pulsating/animated display for Christmas. I know this won't happen for this Christmas, but, every year I keep thinking the same thing. So I'm starting now to see where I can get.
Thanks for reading my query.
Karl
 
The obvious way to do it these days is to use a PIC and triacs to switch the lights - but historically you used motorised switches - a slow AC motor driving a shaft with cams on, the cams operated microswitches.
 
Here's one that will sound like a total Rube Goldberg solution but, it's so crazy it might just work.

Let's say you gather up some photocells and a couple of quad comparator ICs (like the LM348 or siimilar) and some resistors and either triacs or relays, with suitable transistor drivers, for the output.

Get the free audio editor program, Audacity, which has a tone generator built into it. Record a series of tracks, each with a different tone (sine). Edit the tracks so that each tone is present for the intervals you want to have your Xmas lights on for each circuit. Then save the audio file.

Play the audio file in Windows Media player with one of the FFT spectrum displays selected as the "visualizaion". This will give a bar or signal peak at the specified frequencies you chose in Audacity for each track.

Tape the photocells to the monitor screen and wire them to the comparators. Position the cells such that when a frequency is turned ON, the CRT or LCD will "light up" under the photocell and change the cell's resistance (assuming you use somthing like a CdS cell) which will switch the comparator and turn on the output relay or triac.

After Xmas you simply untape the photocells; no harm, no foul. You're back to computing as usual. Unplug everything else and put it away til next year.

I haven't actually tried this but, I can't imagine it wouldn't work as long as the ambient light in the computer room is kept low.

If anybody should happen to give this a shot...let me know how (if?) it worked.

PS: Personally, I like relays. I like the total electrical isolation and simplicity of them, especially when working with the AC mains.
 
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crashsite said:
Here's one that will sound like a total Rube Goldberg solution but, it's so crazy it might just work...

Wow, talk about using a sledge hammer to crack a nut!:D

JimB
 
hi,

>>>Wow, talk about using a sledge hammer to crack a nut!

Well Jim, it is christmas.:rolleyes:

Bi-metal strip switches are a common way to control xmas tree light strings.
 
Sledge Hammers

JimB said:
Wow, talk about using a sledge hammer to crack a nut!:D

Is it really, Jim? Or is it just so fiendishly clever that its utter simplicity baffles the rational mind?

It uses only computer stuff that's either sure to be in the home (or readiy available from the internet). For PC users, anyway (and, there's likely a work-around for the MAC crowd). And an optical computer interface that's so simple that there's not even an IEEE standard for it.

There's absolutely no programming skills or logic design required. Just uses existing programs (Audacity and Windows Media Player). It uses the raw outputs from the comparators to drive the output switches (and that circuit only needs to be designed once and repeated 7 times for an 8 output controller). It's also expandable by adding one or more tone tracks, comparators and output circuits up to the resolution limit of the FFT display (ie: ablity to space the peaks so they don't trip adjacent photocells).

What's more, since the tones only need to be on one stereo channel it should be possible to time (though not sync) the lights to some mono music, on the other channel, within a single audio file. Of course, the music side would need to be carefully recorded so the tones would pop up above the highest music peaks. a bit tricky but, with a healthy dose of AGC, it could be done. Unfortunately, I don't know of a way to force the visualization to ignore one side or the other.

Rather than a sledge hammer, I think of this more as using a feather to flick a flea off a fly's fanny. In fact, the more I think about it, the better I like it. Maybe I should kit it up and try to sell it...next Xmas...
 
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Hmmm...some "playing around" indicates that there are some problems with my idea. The FFT display in the media player isn't as clean as I'd hoped and there's some editing problems in Audacity. But, I've found some work-arounds that I believe will resolve these issues. Some times you have to build the Model T before you can figure out how the Mustang should be implemented.
 
Washing Machine Programmer

karl_ottawa said:
I'm sure this exists in different forms but I haven't found an easy, economical way of doing it yet.
What I'd like to do is have some type of timed rotoray switch system that would turn on a different outlet for each step. I figure I would need 3 to 5 outlets. Each of these outlets would have a set of christmas lights plugged in. So that you could make a pulsating/animated display for Christmas. I know this won't happen for this Christmas, but, every year I keep thinking the same thing. So I'm starting now to see where I can get.
Thanks for reading my query.
Karl

Could you get hold of a programmer out of a very OLD washing machine ?
These used microswitches operated by cams from a motor driven shaft. You would have to speed up the shaft considerably to get a fast pattern.


(This of course assumes that you do without your home brewed beer
"A German priest has found a way to brew beer in his washing machine.
Michael Fey, 45, of Duisburg built a computer interface into the machine
to let it run an automatic brewing programme. It consists of turning
and heating, but no spinning, the Sueddeutsche Zeitung reports. "A
priest without alcohol, that's the wrong combination," he argued.
"Jesus didn't say, take this healthy camomile tea, he offered wine."
The priest brews 30 litres every six weeks, the legal limit for home
brewing, and says he was inspired by the tradition of monks who brewed
beer in a cauldron over a fire. To imitate this technique, he opted for
a toploader washing machine. Before he started brewing, he ran it about
20 times to remove any soap residue. The priest brews in accordance
with the strict German beer regulations, which date back to 1516.")
 
I did something like this once when I was a kid, I used a large tin can that held some kind of juice. open it with a "churchkey" type of can opener
(the type that punches a triangular hole near the edge) Dont cut the top off
like a rotary opener would. Empty out the juice. Then remove the label or if it is painted sand off the paint. Find the center of each end and punch a small hole there. Insert a threaded rod through these holes, It should be long enough to extend a few inches past each end of the can.
Use nuts and lockwashers to secure the can to the rod so it wont slip.
Build a frame out of wood or something that is non-conductive to support the can horizontally by the rod ends, It should be able to rotate in this frame.
Now you need to connect a small motor to slowly rotate the can.
Next use some stiff pieces steel wire screwed to the frame to make contact to the can as it turns. You will need one for the common connection and
one more for each outlet. now wrap strips of tape around the can where the outlet contacts will touch the can, dont tape off the common contact. This will keep the contacts from touching the can and connecting the light circuit. Now to "program" it use a razor knife to cut away the tape where you want the lights to light as the can slowly rotates. Hopefully that is all clear.
Bruce
 
I looked at this bloke's profile.

His last activity was at 9:08 pm (my time, ie. GMT + 10) on the day he posted.

So he has not even read Nigel's post - unless he read them without logging in.

Some times I wonder why we bother.
 
ljcox said:
Some times I wonder why we bother.

...Because we're not really responding for him. the reason we opened his message is because it's something we either want to know or want to comment on and there are enough others doing the same that it makes it worthwhile to put up with a "non-starter" posting it. At least that's my take on it...can't really speak for the rest of youse guys...
 
Yes, I take your point, it does provide us with a discussion point.

But I feel it is rude to start a thread and never return.
 
Yeah, I think it's a bit rude, too but.....if that's the worst "crime" he ever commits in his life, I'd rate it as pretty benign.
 
crashsite said:
...Because we're not really responding for him. the reason we opened his message is because it's something we either want to know or want to comment on and there are enough others doing the same that it makes it worthwhile to put up with a "non-starter" posting it. At least that's my take on it...can't really speak for the rest of youse guys...
Wow...you're a much better person than I am. I'm not even sure why I clicked on this post actually. I have no interest in the title.
 
Beam Me Up, Scotty...

dknguyen said:
Wow...you're a much better person than I am. I'm not even sure why I clicked on this post actually...

Perhaps you're just condemned to chase me across the width and breadth of the galaxy like some character in a bad Star Trek episode....
 
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