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mizitch
Oct 03, 2005, 04:49 PM
Anyone have any ideas on how to run a relay off of an R/C reciever?
help would be aprecieated
Mr.RC-CAM
Oct 03, 2005, 05:42 PM
Take any standard R/C servo.
- Remove the motor and gears, but retain the pot (set it to the mid point).
- Connect one coil side of a low current 5VDC relay to one of the motor wires (pick any one of the two). The other coil connection goes to battery ground (servo black or brown wire).
- Install the hacked servo onto the R/C system and adjust the pot so that it trips at the desired Tx stick position. If the relay operation needs to be reversed, swap the motor wires.

RC-CAM
Chippie
Oct 03, 2005, 05:43 PM
It doesnt necessarily have to be a relay does it? ( current handling...)

there are numerous ccts on th eweb for R/C switch...
mizitch
Oct 03, 2005, 05:46 PM
i was thinking a relay because it could be dpdt so it could run a circut forward or reverse
mizitch
Oct 03, 2005, 05:47 PM
Links would be great
swatson144
Oct 03, 2005, 05:51 PM
You could use this switch to power the relay
http://www.welwyn.demon.co.uk/rcsw/rcsw.htm
swatson144
Oct 03, 2005, 05:53 PM
or this one
http://www.uoguelph.ca/~antoon/gadgets/rc-sw.htm
Malc C
Oct 04, 2005, 04:35 AM
I just added a standard general purpose tranny to the output of a PIC which was programmed as an RC switch, this activated the relay coil and the DPDT relay was used to control the switching of polarity for a small electric motor.
vintage1
Oct 04, 2005, 05:34 AM
i was thinking a relay because it could be dpdt so it could run a circut forward or reverse

A servo will do that.. with motor removed...but the dead band needs adjusting a bit.
markmi
Oct 04, 2005, 08:39 AM
Or for a simpler solution you can use the servo to drive a PCB see attachment. Segments can also be added for other functions, slow fast.

markmi
Malc C
Oct 04, 2005, 11:21 AM
Or for a simpler solution you can use the servo to drive a PCB see attachment. Segments can also be added for other functions, slow fast.

markmi

basically the same principle as the old Tamiya speed controller. In fact if you get hold of one of those and replace the resistors with links made from wire suitable to handle the amps you want to run, that too would work
Norman Adlam
Oct 04, 2005, 11:55 AM
or this one
http://www.uoguelph.ca/~antoon/gadgets/rc-sw.htm

Hi,

If you use this circuit (which works fine!) I'd replace the hard to get IRFZ42 with a NMOS logic level Power FET. That'll ensure it switches hard on or off with the 5V logic available.

Cheers,
vintage1
Oct 04, 2005, 11:59 AM
Nice circuit. You could use two of them for bidirectional control with a dead band in between.

May build that myself for landing lights :D
AndyOne
Oct 04, 2005, 04:02 PM
The problem with the 4013 circuit as published is there is quite often not enough voltage in the receiver output pulse to be certain of getting a logic 1. Some receivers only put out a couple of volts at the servo output. It may not work without a buffer of some sort.

Andy.
mizitch
Oct 04, 2005, 04:53 PM
lil comlex i like mr.rc-cams idea
Nightz
Oct 04, 2005, 08:01 PM
How about a cheap esc for a brushed motor.....gws maybe?
Norman Adlam
Oct 05, 2005, 07:24 AM
lil comlex i like mr.rc-cams idea

Hmmmm, not that more complex, when you consider the fact that you've got to mess around with mechanics, and it may end up a bit less reliable, and slower! :D

In the end it's 'horses for courses', so whatever is best for the individual.

Cheers,
Norman Adlam
Oct 05, 2005, 07:26 AM
The problem with the 4013 circuit as published is there is quite often not enough voltage in the receiver output pulse to be certain of getting a logic 1. Some receivers only put out a couple of volts at the servo output. It may not work without a buffer of some sort.

Andy.

Andy,

I guess you may be right, but I've never seen that problem so far!

Cheers,