"zero" timer for catapult gliders
"zero" timer for catapult gliders
This is a band burner timer that is also the launch grip for your catapult glider. The timer is actuated when you grip the model for launch and starts the countdown when the model is released. At the preprogrammed time the burner is actuated which burns through a rubber band that is holding the wing down in flight mode. Once the band is burned and the wing released the model is in dethermalized (DT) mode and it descends out of any lift (thermal) it happens to be trapped in. The battery and charging jack are located near the nose of the model so that they can stand in for nose weight and the timer board is the launch grip so there is zero effective weight gain from using a DT timer. This is why we call it the "zero" The timer has two band burners on it - one in the front and one in the back so that you can hook it up from either end.
Each full timer is assembled by hand (which accounts for most of the price). If you want a kit of parts to assemble it yourself (you will need basic soldering skills) the price is less. The complete RTF kits is as shown above - fully ready to use in your glider. Just install the timer and fly.
Partial kit - the nichrome wires are installed but the rest of the work: soldering the wires to charger/battery, attaching 3D printed grip plate and sandpaper etc. is left tot he builder.
full kit - you receive a length of nichrome and the various components so that you can assemble the timer yourself. the advantage of this is that you can set all the wire lengths to suite your glider design.
You will need a charger to charge the timer a few times a year. If you already have a hummingbird tiny timer you can use the same charger you just need an adapter cable.
Notes on using the Zero
The battery should last for 70 to 100 burns - this for most of us is more than an entire season’s worth of flying. So you really only need to charge the timer a couple of times a season (unless you are flying A LOT). Always charge BEFORE a flying session, you never want to store the timer fully charged. LiPo batteries are happy with 70-80% charge. Storing LiPos with 100% will damage the battery.
The zero or minimum possible time is 5 sec. This is the default time on your timer when shipped. If you program the timer to run for ten seconds it will actually run for fifteen seconds.
Don’s Cheat Sheet (From Don DeLoach)
1. Long press-> wake up (blue blinks)
2. 3x short presses -> programming mode (solid blue)
3. long press
4. SOLID RED (minutes mode)
5. each short press = 1 min each
6. very long press to go to seconds mode
7. SOLID BLUE
8. each short press = 10 seconds
9. Long press to save this program
10. back to blue blinks (standby mode)
To Fly:
1. one long press-> wake up (blue blinks)
2. one very long press->blue/red flash (timer armed), then release the timer button as you launch the model (timer is running).
3. 3 short presses to stop the timer and return to standby