7. TeleMega¶
Fig. 7.1 TeleMega Board
TeleMega is a 1¼ inch by 3¼ inch circuit board. It was designed to easily fit in a 38mm coupler. Like TeleMetrum, TeleMega has an accelerometer and so it must be mounted so that the board is aligned with the flight axis. It can be mounted either antenna up or down.
TeleMega v2.0 has a few minor changes from v1.0:
- Companion connector matches EasyMega functions
- Serial port connector replaced with servo connector with support for up to 4 PWM channels.
- Radio switched from cc1120 to cc1200.
None of these affect operation using the stock firmware, but they do mean that the device needs different firmware to operate correctly, so make sure you load the right firmware when reflashing the device.
7.1. TeleMega Screw Terminals¶
TeleMega has two sets of nine screw terminals on the end of the board opposite the telemetry antenna. They are as follows:
| Terminal # | Terminal Name | Description |
|---|---|---|
| Top 1 | Switch Input | Switch connection to positive battery terminal |
| Top 2 | Switch Output | Switch connection to flight computer |
| Top 3 | GND | Ground connection for use with external active switch |
| Top 4 | Main - | Main pyro channel connection to pyro circuit |
| Top 5 | Main + | Main pyro channel common connection to battery |
| Top 6 | Apogee - | Apogee pyro channel connection to pyro circuit |
| Top 7 | Apogee + | Apogee pyro channel common connection to battery |
| Top 8 | D - | D pyro channel connection to pyro circuit |
| Top 9 | D + | D pyro channel common connection to battery |
| Bottom 1 | GND | Ground connection for negative pyro battery terminal |
| Bottom 2 | Pyro | Positive pyro battery terminal |
| Bottom 3 | Lipo | Power switch output. Use to connect main battery to pyro battery input |
| Bottom 4 | A - | A pyro channel connection to pyro circuit |
| Bottom 5 | A + | A pyro channel common connection to battery |
| Bottom 6 | B - | B pyro channel connection to pyro circuit |
| Bottom 7 | B + | B pyro channel common connection to battery |
| Bottom 8 | C - | C pyro channel connection to pyro circuit |
| Bottom 9 | C + | C pyro channel common connection to battery |
7.2. Using a Separate Pyro Battery with TeleMega¶
TeleMega provides explicit support for an external pyro battery. All that is required is to remove the jumper between the lipo terminal (Bottom 3) and the pyro terminal (Bottom 2). Then hook the negative pyro battery terminal to ground (Bottom 1) and the positive pyro battery to the pyro battery input (Bottom 2). You can then use the existing pyro screw terminals to hook up all of the pyro charges.
7.3. Using Only One Battery With TeleMega¶
Because TeleMega has built-in support for a separate pyro battery, if you want to fly with just one battery running both the computer and firing the charges, you need to connect the flight computer battery to the pyro circuit. TeleMega has two screw terminals for this—hook a wire from the Lipo terminal (Bottom 3) to the Pyro terminal (Bottom 2).
7.4. Using an Active Switch with TeleMega¶
As explained in Using an External Active Switch Circuit, an external active switch requires three connections, one to the positive battery terminal, one to the flight computer positive input and one to ground.
The positive battery terminal is available on Top terminal 1, the positive flight computer input is on Top terminal 2. Ground is on Top terminal 3.
