wireless button project

Hello, I was wondering if anyone in here might know how I might be able
to control an analog switch with a wireless button? I would like to
control a 4066 analog switch wirelessly. I'm looking for something
that would have real quick response time from whenever my button is
pressed, and the range doesn't have to be more than a few feet. I
don't know anything about wireless, but just seeing all the wireless
mouses, car alarms, toy cars...etc, makes me think that this might be
possible. I'm just not sure how to get started and where to look.
Thanks!
Reply to
panfilero
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Unless you're looking for a learning experience, I'd suggest paging through a magazine such as Nuts & Volts and just buying one of the many transmitter/receiver combintations sold within. Most of the receivers with have, e.g., 5V outputs that you can directly use to control your 4066.
Reply to
Joel Kolstad
Get a wireless doorbell and proceed from there. Should be enough learning.
Reply to
Steven
Its actually not so much as a learning thing for me, I'm trying to design something and if i could get a wireless button that would activate a switch with virtually no time delay and the button be very compact, and the reciever/transiever be very compact as well, it would help me get my project done, but I'm not neccesarily trying to build the wireless part myself. If there's something out there, already made that can do this, thats what I'm looking for.
thanks.
Reply to
panfilero
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Kaszeta Photovoltaic Resources Int'l Tempe Arizona USA snipped-for-privacy@pvri-removethis.biz
Reply to
Bill Kaszeta / Photovoltaic Resources
I don't know if what I want exist, but I need something where I can hook up a button that is on momentarily when pressed to a transciever. And that on the reciever end it enables a switch instanteously only while the button is pushed. I need to be able to push the button repeatedly very quickly and have the switch at the reciever end respond without any noticable delay.
I can't find anything to indicate response time on these circuits at this link. I think there is a little delay in a typical car door opening wireless system, but am not sure.
thank you.
Reply to
panfilero
Well, yes. There is, definitely, a little delay, caused by the wireless part of the system. But you would probably have to measure it in millionths of a second, or less.
The speed of light being what it is, the delay will also increase, the farther apart the transmitter and receiver are.
How much delay can you tolerate?
Reply to
tomg
Forget speed of light. Not an issue.
The delay is caused by a number of factors. The reciever might need to apply AGC to the carrier before it can decode the data, then the reciever will need to validate the data being sent (CRC or some such trick). The data rate will also be a lot less than the 433mhz carrier frequency..
Reply to
CWatters
Hmmm... if the delay is around 1/10 of a second, that would probally be fine. I just need to be able to tap the button as fast as I can with my finger (5 or 6 times a second probally) and the switch turn on and off along with my tapping, with no noticable delay.
What type of transciever/receiver stuff does this? Do you think the one's in car alarms are fast enough? Do you know what is in the wireless mouse?
thanks!
Reply to
panfilero
Not if the cat or the owner are the only ones tripping it.
I know what comes OUT of a wireless mouse?!
Reply to
Steven
For $10 or so you could buy a wireless door bell and play around with it - cheap and easy
David
panfilero wrote:
Reply to
David
no. they trasmit a code and that will delay the response...
often a bluetooth transmitter
the trasmitter/receiver pair from a cheap radio-controlled toy may be the cheapest option - how much range do you need?
Bye. Jasen
Reply to
jasen
I had a similar project where I needed a fast action remote with little delay and good repeating characteristics.
I suggest you go to Walmart, or eBay, or Radio Shack and buy the cheapest wireless racing car toy that they make, take apart the controller and receiver, add suitable batteries and away you go. Some of them will even give you multi-channel control.
As stated by others, the problem with garage door openers is that they send out pulses of coded modulation and it takes time. There may also be a "don't press the button too fast" circuit also known by engineers as a debouncer in such a control. They do generally have good range and reliablity though.
Beachcomber
Reply to
Beachcomber
why is speed an issue? i'm going to be tapping a momentairly on button as fast as i possibly can with my fingers and need a digital gate to be responding just as quick as i can tap.
Reply to
panfilero
Because mechanical switches have contacts that don't just produce one transition when you press them, they produce many - as the contacts "bounce", or make several very short intermittent contacts before finally reaching the desired state. These short intermittent contacts may be as brief as a fraction of a thousandth of a second - but modern electronics will respond to them as if you were tapping the button that fast.
Now you don't want your gate to respond to these many intermittent transition contacts - you just want it to respond to the first contact, each time you press the button, so the system acts as if you have pressed the button once, and not as if you had pressed it dozens of times in the space of a thousandth of a second.
So "debounce" techniques are used.
One is to register the first contact but ignore any other changes for the next, say, tenth of a second. That is long enough for the switch to make final contact and so all the intermittent contacts within that tenth of a second are ignored.
But, if you are pressing and releasing that button more than ten times a second - the debounce circuit will also ignore your presses during the tenth of a second after the first press...
So speed is an issue - if you are pressing and releasing the button faster than the contacts have time to settle, then no "ignore" time will do. Either the ignore time will be too long - and miss your presses, or too short and include contact bounces.
There are alternatives though.
Such as having a "pressed" set of contacts and a "released" set of contacts. When the button goes down, it makes the "press" contacts. When the button comes up, it releases the "press" contacts, travels enough distance to make sure that the "press" contacts are well and truly seperated and then makes a set of "release" contacts.
When you press the button, the circuit responds to the first "press" contact but ignores all the others as being bounces. When it gets a "release" contact, it resets waiting for the next "press" contact and ignores all the subsequent "release" contacts as also being bounces.
Such a circuit can respond to a train of button presses faster than a simple "ignore" time delay.
Who would have thought something as simple as pressing a button could be so complicated? However, it is, when electronics are connected to the button contacts.
So that is why people are wondering why you want to press the button repeatedly and what the whole project is about. It may then be possible to suggest a simpler approach that doesn't need you to press the button that frequently, or even at all..
Reply to
Palindr☻me
Rich Grise wrote in news: snipped-for-privacy@example.net:
Rich,
These little RS ZIPZAP cars work very well. The receiver is tiney, and has two outputs in an H-bridge configuration for forward-reverse, and two open collector outputs for left-right steering. A little external logic gives you a lot of control options. Adding more wire for the receiver antenna really extends the range. I haven't done it, but you could reduce the transmitter size by cutting up the xmtr PCB and getting rid of the charger circuit.
I used one of these to remote control a gag gift for the departing President of our college.
Ken
Reply to
Ken Moffett
Just wondering whether using a photo diode (or such) sitting behind a panel might be a simple way of avoiding the switch bounce problem. In this case your 'button presssing' would actual be placing your finger over a hole in the panel to change the light impinging on the photo diode/transistor.
Alternatively you could mock up a simple mechanical 'shutter' you press that controlled the light falling on the diode/transistor
Cheers
David
Pal> panfilero wrote:
Reply to
quietguy
Even photosensors have a tendency to produce more than one transition for each interruption. Unless designed not to, they can respond to the changing reflection from fingerprint skin variations as your finger is brought near the switching point. Similarly with a mechanical shutter, particularly if there are multiple ambient light sources and especially if they are ac-driven..
Such things are never quitre as easy as they first might appear..
Reply to
Palindr☻me
I was just being flippant about the "delay" issue that the OP seemed too worried about.
- Tom
Reply to
tomg

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