help converting a servo output to on/off

[cobra1]

i am currently working on a little project, i have a 2.4ghz transmitter and receiver.

the receiver is setup for use with servos which i belive require a pulsed signal, and the transmitter uses a potentiometer to control the pulsed signal to the servo,

what i want to do is remove the potentiometer and replace it with a push button, and at the receiver end intead of a pulsed output i get an on/off output.

i tried potential divider, so i could get a setpoint at which i would get an on/off output, but all i get is a dimmer, the output is always on but it goes dim when i press the button.

does anyone have any other ideas??

 

[jpanhalt]

It might be easier to look up "kill switch". All of the larger gasoline powered models have them. The early ones were electro-mechanical (i.e., used a servo and microswitch). Modern ones are purely electronic.

John

 

[cobra1]

hi john

this isnt for use on a model its going to be used as a launch system for high powered rockets.

i would like to use all 4 channels if possible, 1 channel per launch pad

 

[jpanhalt]

The principle is the same, isn't it. A kill switch grounds the ignition, but you could wire it another way or use a P-channel mosfet to provide real power by grounding its gate.

My recommendation was based on using something that is essentially already incorporated into the 2.4 GHz TX and RX, rather than hacking into them. Most modern TX used for models have several switched channels that are proportional, but can be set up to effectively be on or off.

Of course, if you are using homemade RX/TX, then that is not the case. Still, there are designs on the Internet for electronic switches based on either short blips or pulse width from typical hobby transmitters.

They are so inexpensive, that I have not bothered to make one.

John

 

[cobra1]

ohh now i see what you mean, i missunderstood your first post.

i am using a shop bought unit that i has just took apart for its circuits.

i will have a look for this kill switch and see if it will work for me