wireless on/off stopwatch - Page 2 - Electronic Circuits Projects Diagrams Free

foringa · 7th July 2009, 09:29 AM

Quote:

Originally Posted by MrDEB

as long as there isn't alot of traffic on the channel you select.
there are IC's that do all the DTMF stuff. All on one chip.
you just need to build it.
I looked at Ramsey Electronic kits - has possibilities

I saw this wireless trip sensor at ramseys

flat5 · 7th July 2009, 01:03 PM

I think model airplane xmitters & receivers is better than walky talkies. They are a one way system. You don't need to pay for a two way system. They are easy to adapt/modify for your purpose. Walkies, not so much.
They should have the range you require.

MrDEB · 7th July 2009, 01:28 PM

to build from scratch or a kit or ready to use?
here are some circuits that may do what you want but will require some work.
radio remote control RC using DTMF circuit diagram

Electronic Kits, Circuits and Projects

FM Transmitters«RF«Circuits/Schematics Directory

Radio Remote Control using DTMF « Transmitters « RF « Circuits/Schematics Directory

walkie talkies was just a suggestion for an easy way to get the job done. while not ideal but would work.
would still need to add DTMF circuits.

hope this helps

MrDEB · 7th July 2009, 01:34 PM

RXD433 transmitter receiver modules

foringa · 9th July 2009, 04:29 AM

Quote:

Originally Posted by MrDEB

RXD433 transmitter receiver modules

Do you think you could build this project and if so how m
ford79pu5@aol.com

MrDEB · 9th July 2009, 12:46 PM

I am not the best when it comes to RF circuits.
the DTMF is no problem.
Also how fast do you want this?
If you can't locate someone else then maybe.

flat5 · 10th July 2009, 06:11 PM

Why do I bother?

MrDEB · 10th July 2009, 08:29 PM

you couldn't find someone more qualified
my suggestion is use a 2 way radio then connect a DTMF module to them.
If you can't find someone then yes I will build you a unit.
the easiest circuit (parts location?) is

radio remote control RC using DTMF circuit diagram

MrDEB · 11th July 2009, 01:24 AM

Model airplan/car/etc transmitters etc might be the easy way to go.
Tried locating DTMF vhips etc but really no luck.
Then it hit me- why reinvent the wheel?
Get a simple 1 or 2 channel RC transmitter receiver then attach a micro switch or ? to the start gate then when the gate opens the transmitter sends a signal to the receiver and BAM you start the stopwatch.
couldn't be simpler.
Look on Ebay for used transmitter/ receiver sets

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7th July 2009, 01:03 PM	#17
flat5	I think model airplane xmitters & receivers is better than walky talkies. They are a one way system. You don't need to pay for a two way system. They are easy to adapt/modify for your purpose. Walkies, not so much. They should have the range you require.

7th July 2009, 01:28 PM	#18
MrDEB	not sure of your electronics expertise to build from scratch or a kit or ready to use? here are some circuits that may do what you want but will require some work. radio remote control RC using DTMF circuit diagram Electronic Kits, Circuits and Projects FM Transmitters«RF«Circuits/Schematics Directory Radio Remote Control using DTMF « Transmitters « RF « Circuits/Schematics Directory walkie talkies was just a suggestion for an easy way to get the job done. while not ideal but would work. would still need to add DTMF circuits. hope this helps

7th July 2009, 01:34 PM	#19
MrDEB	look at Ramsy again RXD433 transmitter receiver modules

9th July 2009, 12:46 PM	#21
MrDEB	possiable but! I am not the best when it comes to RF circuits. the DTMF is no problem. Also how fast do you want this? If you can't locate someone else then maybe.

10th July 2009, 08:29 PM	#23
MrDEB	I said IF you couldn't find someone more qualified my suggestion is use a 2 way radio then connect a DTMF module to them. If you can't find someone then yes I will build you a unit. the easiest circuit (parts location?) is radio remote control RC using DTMF circuit diagram

11th July 2009, 01:24 AM	#24
MrDEB	Another thought= RC transmitter/ receiver Model airplan/car/etc transmitters etc might be the easy way to go. Tried locating DTMF vhips etc but really no luck. Then it hit me- why reinvent the wheel? Get a simple 1 or 2 channel RC transmitter receiver then attach a micro switch or ? to the start gate then when the gate opens the transmitter sends a signal to the receiver and BAM you start the stopwatch. couldn't be simpler. Look on Ebay for used transmitter/ receiver sets