The MiniTimer3 Staging Electronics is a countdown timer circuit with some extra brains that it can tell if everything is OK to fire off the igniter. This built-in level of safety is the reason we sell this particular electronic gizmo.

The brains of the unit automatically detect lift-off of the rocket. Once that occurs, it starts its own internal countdown, and then sends electricty to the igniter to fire off the 2nd stage motor.

For example, you desire to fire the second stage of the rocket when the rocket is three seconds in the air following lift-off. You would set the timer prior to installing it in the rocket, which is simply holding down the little "program" button for a duration of three seconds when you turn it on. Then you put the unit into the rocket and hook up the igniter into the second stage.

When the rocket sits on the pad, the electronic brain's G-sensor (which senses acceleration) is looking for a sustained acceleration of 2.1 G's. If that acceleration threshold it met, it determines the rocket has successfully launched. It's next step is to determine how much time has lapsed since launch, and when the three seconds (for this example) has passed, it sends electricity to the igniter to fire off the second stage. As you can see, it is very simple to use.

Another example of the simplicity is that the same battery that powers the circuitry also supplies the power to fire off the igniter. This eliminates the need to take a second battery onboard the rocket.

Can it be tricked into thinking a launched has occurred?

It is not likely. The threshold of 2.1 G's has to be maintained for 0.5 seconds, which is a long time in rocketry. You would not trigger it by picking up the rocket as it sits on the launch pad, nor by knocking the rocket over accidentally. The G-sensor must be oriented properly (this end up) so that it can't be false-triggered.

But with any rocketry electronics, you should practice common-sense safety procedures. For example, don't power it up by connecting the battery until the rocket is already on the launch pad and everything else is prepped for flight.

• Can be used with cluster motors!
  
  
• It is easy to set delay time, and this can be done right at the launch field. The timer is adjustable from 0.6 seconds to over 60 seconds in 0.1 second steps.
  
  
• There is a beeper on the unit. This does three things:

1. Provides igniter continuity check - It beeps when you hook up the igniter, letting you know everything is hooked up properly.
   
   
2. Power-up reporting of current delay time setting - After you set the delay time by holding down the "program" button, the unit will beep back the time so you can confirm everything is set correctly.
   
   
3. Post-flight siren - It makes a siren noise after it is done working. This gives you an audible aid to help you find the rocket after it has landed.

• High accuracy digital time setting is retained in EEPROM memory even with power removed. This means is that once you set the time, it stays in memory forever (or until you set in a new time).
  
  
• Uses secure screw-down terminal blocks for battery and igniter. This means there is no soldering required to hook anything up. All you need is a small screwdriver to attach the wires.
  
  
• Rugged "surface-mount" construction and internal self-diagnostics assure reliability.
  
  
• Backed by PerfectFlite's three year warranty.
  
  
• Can be used for other things too. Use it to fire off ejection charges instead of using the rocket motor's built-in ejection charge.

Operating voltage: 4.8V to 10.5 V (3.0V to 4.8V at half current rating)

Operating current: 1.0 ma no continuity, 3.0 ma with continuity

Maximum firing current: 97.6A for 1 ms, 64.5A for 10 ms, 33.9A for 1 second

Continuity check current: 75 uA/V

Timing range: 0.6 second to over 60 seconds in 0.1 second steps

Timing accuracy: +/- 3% typical

Operating temperature: 0C to 70C