I posted this question on RC Universe, but have got no response. I want to reverse a servo with a switch. In other words, when the switch is up, the servo is normal and when the switch is down, the servo is reversed. Sounds simple, but I can't figure it out. Has anyone done this? Any ideas?
It might help if you shed a bit more light on what you're trying to do, but if it's an otherwise uncontrolled servo (ie: *not* a servo for rudder/elevator/ailerons or throttle) such things are usually accomplished using free mixer(s)...
/daytripper
You need to use a feature called "offset" in the programmable mix. Se
the same channel to master and slave and use "-100%" as the value. Assign the switch you want
-- Ledbette
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| I posted this question on RC Universe, but have got no response. | I want to reverse a servo with a switch. In other words, when the switch is | up, the servo is normal and when the switch is down, the servo is reversed. | Sounds simple, but I can't figure it out. Has anyone done this? Any ideas?
A switch on your TX or on the servo itself?
If it's on your TX, then that depends on your TX. Perhaps if your TX allows negative values for dual rates? Or can reverse a servo in different flight modes? I don't think most TXs will make this easy to do ...
If it's on the servo, then the normal way to reverse a servo is to swap the motor wires, and swap the two outer wires on the pot. Or put a servo reverser gadget between the RX and the servo.
The former would be difficult to trigger with a switch -- you'd need to have all sorts of wires going around.
The latter could be done by bypassing the servo reverse on the signal line with the switch in one position, and enabling it in the other position. You could do that with a SPDT switch pretty easily -- in position one, the servo gets the signal wire from the RX, in position two, it comes from the servo reverser.
| A switch on your TX or on the servo itself?
Nevermind, the subject sort of answers that.
Tried that, didn't work. I did get a reply at RC Universe from a guy in the UK though. Tried his suggestion, worked perfectly. Gotta love those Brits. For those interested, here's how it's done to reverse the elevator servo with switch A. Use 2 program mixes, say P-1 and P-2
On P-1 MASTER=ELEV SLAVE=ELEV TRIM=ON LINK=ON SW=A POS=DOWN Set both limits at -100%
Then make P-2 exactly the same as P-1
I don't fully understand why this works, but it does.
42
Oh my.
If that ain't a Crash Switch, I don't know what is...
/daytripper
Well, a lot of mixes could be thought of as crash switches I suppose. I sure wouldn't want to hit the snaproll switch while on landing approach 5ft off the runway.
42
ahahahahahahaha!
As a matter of fact, been there, did that, took an evening to put my Fun Fly back together again. The next day I repeated the same stoopid trick, only this time 1.01 mistakes high, which let me recover with around a foot of altitude to spare. That time it sunk in deep enough that I haven't hit that snap roll switch in a landing sequence again :-)
/daytripper (the radio folks give us plenty of rope to hang ourselves ;-)
Forgive my ignorance and curiosity, but WHY would you want to do such a ting?
In article , Robert Roland wrote: | On Wed, 10 Oct 2007 15:40:25 -0700, "42etus" | wrote: | | >reverse the elevator servo | >with switch A. | | Forgive my ignorance and curiosity, but WHY would you want to do such | a ting?
My guess is that he's trying to make an `inverted' switch to get rid of the `where down is up and up is expensive' thing. Well, not get rid of it, but turn it into `where up is up and down is expensive' -- at least until you are not inverted, but forget to switch the switch back ...
And if so, yes, this sounds like a recipe for rekitting ...
For some people the radio itself is a crash switch.
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