Hey Perrti!
I am not sure what exactly you are looking for, but you mention an overview, so here it is.
The timer functions as the "smart" throttle for the electric setup. It connects to the electronic speed control (ESC) just like the throttle channel on a rc receiver would. So it sets the throttle setting, and turns the motor on and off to set the time limits of the flight---just like the transmitter stick would.
Ok so that's the basic functionality.
The timers I have used, JMP-2, Ztron CLT3, Hubin FM3a support, these "essential" functions.
1) There is a run-up time. Once the setup is armed, there is an adjustable time which allows you to throttle the motor down to some value (I turn it off) while you walk out to pick up the handle. After the time delay (I set 20 seconds) the motor comes on to the first throttle setting.
2) Generally you are allowed two throttle settings--a starting setting and a final setting. Originally this was done because during the run the battery voltage drops, and if you kept the throttle the same, your rpm would drop too. On the JMP-2 and Ztron, the throttle will ramp linearly from the starting value to the final value, which can be made to roughly compensate for the voltage drop. I don't recall right now how the my specific Hubin timer does it, but I am sure he has a version which works in a similar manner.
I mention now that most of us do NOT use feature (2) because we are using the governor mode built into the ESC--and this will keep rpm constant during the flight, and also during maneuvering.
3) At or near the end of the flight, the timer gives out a couple of warning "blips" to signify that it is about finished. Some timers allow you to program it off, some don't.
Of the three I have all have performed excellently. They all have particular strengths and some weaknesses. I think I made a JMP-2-Ztron CLT-3 review post a couple of years ago. I think if you search for "CLT3" you will find it for the particulars.
Oh yes, of the three varieties I have, each one cost $30 +S&H. All are worth the money.
My own advice is that I would NOT get a timer that doesn't have feature 1. I think the $30 timers represent the minimal functionality that I want.
ps. The three also have a landing gear functionality--they will drive a servo which will retract the gear and extend it--if you have retractable gear of course!
Topic: The Timer Thread - or what is available, how do they do. (Read 1139 times)
