receycling an activator switch from a remote controlled device

Discussion in 'The Projects Forum' started by Gibrril, Oct 12, 2013.

  1. Gibrril

    Thread Starter New Member

    Oct 12, 2013
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    Hi,

    I would like to strip the activator switch of a remote controled device and use to to make another device remote controlled.
    In this particular case I would like to attach the remote controled switch to an electronic cigarette so it can be activated from a distance.
    Since this "remote controlled e-cigarette" has to be used for theatrical purposes, the attached remote controlled switch needs to be as small as possible.

    Any ideas on specific switches or on a procedure on how to build this cigarette would be very, very welcome.

    Thanks a lot,

    Gibrril
     
  2. DickCappels

    Moderator

    Aug 21, 2008
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    How much is your budget for design consultation, and how much are your budgets for materials and tooling?
     
  3. KMoffett

    AAC Fanatic!

    Dec 19, 2007
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    Any number of solutions. "small as possible" is a relative concept. Can you elaborate on how it will be used on stage?

    Ken
     
  4. Gibrril

    Thread Starter New Member

    Oct 12, 2013
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    Hi,

    Thanks for the replies!
    The budget is as of yet undetermined (i still have free reign)
    the size has to be quite small, or at least quite flat: it has to fit inside a piece of carpet.
    Thanks a lot,

    Gibrril
     
  5. KMoffett

    AAC Fanatic!

    Dec 19, 2007
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    Rather than us coming up with ideas that you will find don't fit the image in your head, spec the maximum dimensions that you could accept. "it has to fit inside a piece of carpet" doesn't tell me much.
    The repeat: "Can you elaborate on how it will be used on stage?"

    Ken
     
    Last edited: Oct 13, 2013
  6. Gibrril

    Thread Starter New Member

    Oct 12, 2013
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    Hi,
    You're right. The exact dimensions:
    The wireless device can't be higher than 1cm.
    The width can't be more than 3 cm.
    The length does not matter all that much but max 60cm.

    The idea is that the entire "device" will be stored inside of a small close up pad. This pad needs to be carried on stage while it's still rolled up.
    Then it will be rolled out on a table and the performance will start.
    It's very important that all sides can be shown (allthough the pad will never be shown from all sides explicitly, spectators will be looking at it from allmost anywhere except behind the performer.

    A tube that runs inside of the pad from the cigarette to the center of the pad will make sure that a puff of smoke appears in the center of the pad every time te cigarette is activated.
    The performer will be seated, so by pressing the legs together, the button to activate the cigarette can be pushed.
    We have tried it by just pushing down on the pad, on top of the pushbutton, but that really gives away a lot of the method... We need at least eight puffs of smoke during the performance, and pushing down on the pad in the exact same spot eight times is really suspicious...
    also it would help a great deal if the performer had both hands to work with instead of having one out of the picture because it has to push the button.

    I hope this helps. If you need more specific information, hust let me know!

    Thanks a lot,
    Gibrril
     
  7. KMoffett

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    Dec 19, 2007
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    Last edited: Oct 14, 2013
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  8. Gibrril

    Thread Starter New Member

    Oct 12, 2013
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    Hi,

    Thanks so much for the links.
    Quick question thow:
    When I click on the link, I get the detailed explanation and a pricetag of 7,950 $, when I see the same product listed in an overview of the available RF receivers, it's listed as 7,95 $. So, this may sound really stupid but are we talking 8 dollars or 8000?
    (here in Belgium 7,950 or 7.950 are the same when it comes to prices...)
    Thanks a lot,

    Gibrril
     
  9. KMoffett

    AAC Fanatic!

    Dec 19, 2007
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    $8US and $7.95US. I didn't know you were in the other side of the pond. It helps if you put you general location in your profile. These may be available through an EU vendor for cheaper shipping.

    I ordered a pair yesterday, to see if my recommendation works. I'm assuming you can get at the switch contacts in the e-cigarette.

    Ken
     
  10. Gibrril

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    Oct 12, 2013
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    Thanks a lot!
     
  11. KMoffett

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    Dec 19, 2007
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    Got my modules today. Seems to work well...but...pushing and holding the switch to the transmitter results in a single 1.5mS pulse at the receiver's output. Repeated pushes gives you repeated 1.5mS pulses.

    1. How long do you need to have the smoke emitted at each trigger?

    2. How much current does the e-cigarette draw from its internal battery?

    Ken
     
  12. KMoffett

    AAC Fanatic!

    Dec 19, 2007
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    Adding a 555 astable oscillator to the transmitter holds the receiver output ON as long as the transmitter switch is ON. The attached circuit should do what you want. I didn't spec the MOSFET (Q1) because I don't know the current that the e-cigarette's switch must pass. You can check this by placing an ammeter across the e-cigarette's switch contacts.

    Ken
     
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  13. Gibrril

    Thread Starter New Member

    Oct 12, 2013
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    Hi thanks a lot!

    How thick is that 555 astable oscillator?

    Thanks again!
     
  14. Gibrril

    Thread Starter New Member

    Oct 12, 2013
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    Extra question: are there any heat issues? (I am going to put this in the neoprene part of a rubber mat)

    Thanks so much again,
    Gibrril
     
  15. KMoffett

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    Dec 19, 2007
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    The 555 in the DIP package are about 5mm thick if the legs are spread out horizontally. There are smaller surface mount packages, but unless you are into making your own surface mount PCB, they are hard to work with. I don't foresee any heat issues...except the e-cigarette, that I know nothing about.

    Connecting the two lithium coin batteries without holders, that may be too thick, would take some thought. Again, it's back to how thick can the be?

    Ken
     
  16. Gibrril

    Thread Starter New Member

    Oct 12, 2013
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    I can hide things in the mat that are as thick as 7 mm, 8mm still fits, but it's very, very close. It also depends on how wide the elements are. The smaller they are, the closer they can be to 8 mm thick: I still have to be able to roll the mat up and spread it back out without showing any strange bobbles.
     
  17. KMoffett

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    Dec 19, 2007
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    OK, I answered before I had my morning coffee. You don't need to worry about the size of the 555 or the associated transmitter components. These will be on the performer's body. As for the coin batteries for the receiver in the carpet, you can have a battery store weld tabs on and between two cells, to keep them flat, with no holder.

    In my experimentation, the receiver doesn't need an antenna. In fact it would cause it to pick up random, stray signals that would trigger the smoke. Since this is in an unlicensed industrial frequency band with a receiver that is an overly sensitive super regenerative circuit, and with no encryption, you may want to test it in the performance environment...before you use it. In mine, I added a unfiltered MOSFET and LED to watch the incoming random noise.

    Ken
     
    Last edited: Oct 19, 2013
  18. Gibrril

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    Oct 12, 2013
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    Ok, great

    Thanks a lot!
     
  19. KMoffett

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    Well...a little more experimenting. I must be in an RF noisy environment. I get a lot of brief, false triggering pulses. I have the transmitter sending a oscillating signal to hold the receiver output on. So, I decided to try and detect just that frequency on the receiver end. I added an LM567 tone detector IC. That seems to make the system more dependable. With microcontrollers, they used binary coding and decoding to pair the transmitter to the receiver. But this should work. It adds a little more circuitry to the receiver, but with "dead bug" layout it should still be pretty thin.

    With no antenna on the receiver I got about 100 feet reliable switching.

    Ken
     
    Last edited: Oct 22, 2013
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  20. Gibrril

    Thread Starter New Member

    Oct 12, 2013
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    Hi,

    Thanks again! (sorry for the deleyed response)
    I'll let you know how it pans out.

    Thanks a thousand,

    Gibrril
     
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