The Climb_and_Dive timer is both an active timer and a governor timer with all user settings programmable via a wireless Bluetooth app.

It consists of a PCB backpack ready to solder onto a Seeed Studio Xiao nRF52840 microcontroller development board. After soldering together and loading the open source code you will have a very advanced but still user friendly timer.

What do I need to make one?

There are two parts required to make a finished timer:

The first part is the Climb_and_Dive backpack assembly. It includes: (1) Climb_and_Dive backpack; assembled, tested and ready to go, plus (1) 5 pin strip of right angle breakaway header.

The second part is a Seeed Studio Xiao nRF52840 microcontroller board. I will supply it preprogrammed with the latest timer code plus (2) 7 pin strips of breakaway header plus (1) JST-YRC battery connector with leads.

Both parts are required to assemble a complete unit. I split them up in case you wanted to source and program your own microcontroller board.

NOTE: The kit comes unassembled, soldering skills are required to join the boards together.

Full detailed assembly and operating instructions can be found here:

Climb_and_Dive Timer - Assembly and Operating Instructions.

What motivated you make it?

Like it or not, electric power is the future of control line model aviation. I found there is a limited selection of affordable timers with advanced features. Using the latest microcontrollers, there's no need to break the bank nor make things overly complicated just to enjoy a day at the flying field.

What makes it different from other control line timers?

• Keeping it as a DIY project keeps the costs down. Using an assembled PCB in a backpack format greatly simplifies wiring. Pairing it with an off-the-shelf microcontroller reduces complexity.

• The timer code is programmed in CircuitPython. Making it super easy to program and keep up to date with the latest version.

• The timer code combines advanced features found in several other timers into one low cost package.

• The circuitboard includes a 3 axis accelerometer. All three axis outputs are routed through a low pass filter before passing to the microcontroller input pins. This allows the timer to act as an active controller to boost the throttle in a climb and reduce it in a dive. A desirable feature to help keep the model velocity more consistent.

• It also includes the necessary RPM signal conditioning circuitry to convert the analog motor voltage signal into a digital output. This allows the timer to control the motor RPM and hold it steady through a governing PID control loop. Additionally, the motor shuts down instantly in a crash or nose-over to protect the electrical system from overcurrent.

• Best of all, user settings are programmable via a wireless Bluetooth connection using a free app.

• It's open source. Please hack away and share your own innovations and improvements.