Inside of battery box with main battery and long range RC receiver.
Both, the BQ40Z80 battery management system and long range RC receiver are connected by I2C/SMB, routed to Turtle Rover electronics hat. That allows readout of all battery parameters as well as RC receiver parameters like link status, link quality, channel values etc. Hence a fully transparent and monitorable system. There is a provision for RS232 that may connect additional equipment inside the box to the electronic hat in the future (e.g. GPS).
Battery charger or external power socket on RH side.
The external charger or power socket has a direct battery management system connection. That allows an external power supply to charge the battery or power the entire Turtle Rover, e.g. from a solar panel or auxiliary battery. But external equipment (top mount) can also draw battery power for its own supply.
Top view of battery box mounted on rear bracket, holding the WLAN and long range RC antenna sockets.
Additional press nuts on the rovers rear bracket allowing easy installation of equipment on top and in combination with the main bracket fix points.
Pass-through of WLAN antenna cable into main electronics box. LH the battery harness.
WLAN antenna socket back side. Also shown the battery harness pass-through.
Rear bracket modified with additional press nuts and routing of WLAN antenna cable.
The WLAN cable uses a U.FL (IPEX) connector for a direct connection the modified Raspberry Pi 3 with external antenna socket. This way, no additional WLAN module is required.
Just modified a Raspberry Pi 3 to accept an external WiFi/Bluetooth antenna via U-FL socket.
External antenna connected.
After successfully testing of my G7RGQ antenna here my built details:
In red the dimensions I ended up with.
With above dimensions the antenna is tuned to about -22dB return loss at 1090MHz when placed inside the PVC tube.
Here is another one. Huge thing this time, designed for 433MHz, polarization RHCP. For dimensions etc. see design description below.
Here is another quadrifilar helix antenna design, this time for ADSB (aircraft mode-S transponder) reception at 1090 MHz. Unlike other antenna types this antenna has a spherical coverage with 120° 3dB beamwidth and estimated peak gain of 4.6dBi at 1090MHz.