[englishhaunter]

Hi everyone. I am looking for help with a prop I am making at the moment. It is a small hand operated morse code/telegraph machine. My question is how to make the unit move up and down in a random way, to simulate the original action, as discreetly as possible. My initial thinking was to connect the wooden finger plate to a small 12v push/pull solenoid I have and connect to a 12v supply. I have used the old tried and tested fluorescent strip light starter motor for my 240v props, to give a random effect with my lights, but cannot think of an alternative for 12v. Any ideas?

 

[The Pod]

I would think something like a candle flicker LED (http://shop.evilmadscientist.com/productsmenu/partsmenu/353) wired to a simple transistor might work.

 

[englishhaunter]

Thanks for the reply The Pod. I may have given the wrong impression with the way I worded the post. My intention is to have the long arm move up and down as it would when sending a message, so I would need some "mechanism" in place to do this but powered by a power supply that gives an intermittent charge, making the movement "quick, slow, quick, quick, slow" etc ( sounds like a dance I used to do!)

 

[J-Man]

To get the random true to life effect you want, you'll need a programmable microcontroller.

 

[englishhaunter]

Thanks J-Man, I was hoping not to go down that route but it might have to be a last resort if no other alternatives come up.

 

[J-Man]

To get a "real" look to this there's probably no other way. I can build you a small microcontroller pre-programmed to get the effect you want if you're not familiar with writing code. Let me know if you're interested.

 

[The Pod]

you would still use a 12v solenoid to move the arm. The flicker LED is to give the random on/off and the transistor acts as the switch to turn the solenoid on/off.

 

[Setarcos]

I would have to go with J-Man on this. To get a truly accurate simulation of sending Morse code will need some type of programmable controller.

You still need to work out the mechanical aspects of depressing the key. A solenoid would certainly work, but may add it's own noise when active.

 

[J-Man]

The Pod's suggestion would no doubt make the relay or solenoid chatter, but it probably wouldn't appear "real".

 

[tryingtolearn]

Well I know this might be way outside the box so to speak.. and not really sure how much of that arm pivots up and down so not sure if this would even work.
But what if you were to place that morse code machine on a "box platform" that you build so it looks like its meant to be resting on it, inside the box...you could have a small motor with a cam attached to it and a cam follower that raises up and down that pushes the morse code arm from underneath. A cam wheel with various "bumps" would create the random "clicking" movement. It wouldn't need to be a large motor since it wont have to move much weight. The only downside I see is that you would have to drill though the black base of the morse code machine to allow the cam follower to push the metal part of the arm up and down. Don't know if that makes sense but was just a thought.

 

[J-Man]

Well I know this might be way outside the box so to speak.. and not really sure how much of that arm pivots up and down so not sure if this would even work.
But what if you were to place that morse code machine on a "box platform" that you build so it looks like its meant to be resting on it, inside the box...you could have a small motor with a cam attached to it and a cam follower that raises up and down that pushes the morse code arm from underneath. A cam wheel with various "bumps" would create the random "clicking" movement. It wouldn't need to be a large motor since it wont have to move much weight. The only downside I see is that you would have to drill though the black base of the morse code machine to allow the cam follower to push the metal part of the arm up and down. Don't know if that makes sense but was just a thought.

Well again, while that would provide movement, it would be a very short repeated pattern that wouldn't look real. The key to something like this is to give the illusion that a ghost is actually tapping out morse code.

 

[annamarykahn]

how about tying a fishing line to the mechanism, though the bottom and securely tied to the floor or something like that ... then a motor with something like randomly spaced dowels on a circular disk ... the motor spins the disk and the dowels push against the fishing line, pulling the finger mechanism down? the speed of the motor would determine how fast the mechanism moves and the spacing between dowels would simulate a random motion ... using 2 or more dowels beside each other would be a longer pull, simulating a dash, while a single dowel would be a dash ... if you wanted you could "program" the disk to send a message ... but that is probably getting too complicated ...

obviously, i haven't tried this so i don't know if it would be practical and what other issues you might run into, but this might be something that is relatively simple ... at least compared to programming a real controller ... or not ?

amk

 

[J-Man]

how about tying a fishing line to the mechanism, though the bottom and securely tied to the floor or something like that ... then a motor with something like randomly spaced dowels on a circular disk ... the motor spins the disk and the dowels push against the fishing line, pulling the finger mechanism down? the speed of the motor would determine how fast the mechanism moves and the spacing between dowels would simulate a random motion ... using 2 or more dowels beside each other would be a longer pull, simulating a dash, while a single dowel would be a dash ... if you wanted you could "program" the disk to send a message ... but that is probably getting too complicated ...

obviously, i haven't tried this so i don't know if it would be practical and what other issues you might run into, but this might be something that is relatively simple ... at least compared to programming a real controller ... or not ?

amk

Another thought but unfortunately the same problem as the cam idea. Every revolution of the disk would produce the same short repeated pattern. Not very life-like.

 

[englishhaunter]

Damn these time differences between the UK and USA! Thanks for all the suggestions. I think for the realistic effect I'm after, J-Man seems to have the most reliable option at the moment, and depending on cost, might be the one to go for.

 

[bfjou812]

If you have access to a Prop 1 controller or a Stamp Basic controller there is a lot of pre-written code online for random movement. I used some for a demo on a small prop I made years ago. It might require some tweaking , but there is a lot of support online for those controllers. Pods idea is a good one also ,as far as the noise goes , the telegraph keys aren't silent when operated .