Power Source: 3.3V (from a DC/DC converter)

Antenna: SMA 1/2 wave rubber antenna

Code: https://github.com/UKHASnet/UKHASnet_Firmware/tree/master/arduino_gateway

1x Stripboard, cut to size so all parts fit with 1 hole to spare before edge

1x 28DIP ATMega328P

• Farnell 1715487 - £2.37 each

1x RFM69[H]W

• HAB Supplies (max 20mW) - £3.59 each
• HopeRF (100mW) - € 3,22 each

1x TO-92 MCP1700 3.3V LDO

• Farnell 1296588 - £0.26 each

1x SMA 1/2 wave rubber antennaIdeetron SDK4-868-SMA - €7.40 each

1x 28-pin DIP Socket

1x SMA board connector (HAB supplies has them)

• Solder 28pin DIL IC socket to the strip board
• Cut traces along the centre of the socket
• Check that there is no conductivity between the two halves

• Connect voltage output to Vcc as well as ground
• Solder header for Serial (Tx and Rx) (optional)

• Program the ATmega328 with the arduino bootloader
• Upload simple script to the micro
• Test that everything is working

• Solder connecting wires to RFM69HW (GND, NSS, SCK, MISO, MOSI)
• Line up with the ATmega328's corresponding pins. You'll need to bend your connecting wires a bit to fit through the holes in the strip board. Solder these in place.
• The other 2 pins that need to be connected are VCC and DIO0 which are best connected with insulated wire.
  • VCC → 3.3v
  • DIO0 → pin 2 (Interrupt 0)

• Upload gateway script to test RFM69HW
• Check either with Funcube or that it is repeating to other nodes
  • Its been found that some modules are slightly off frequency and so need adjustment to match. The easist way is to use a funcube or RTL dongle and then adjust the frequency to line up with other nodes.

• Solder SMA connector to ANT and GND pins

• As the current arduino is programmed just to use its internal oscillator it has a special board identification which needs to be added to your IDE. You need to find the boards.txt and add to the end

##############################################################

atmega328bb.name=ATmega328 on a breadboard (8 MHz internal clock)

atmega328bb.upload.protocol=stk500
atmega328bb.upload.maximum_size=30720
atmega328bb.upload.speed=57600

atmega328bb.bootloader.low_fuses=0xE2
atmega328bb.bootloader.high_fuses=0xDA
atmega328bb.bootloader.extended_fuses=0x07
atmega328bb.bootloader.path=arduino:atmega
atmega328bb.bootloader.file=ATmegaBOOT_168_atmega328_pro_8MHz.hex
atmega328bb.bootloader.unlock_bits=0x3F
atmega328bb.bootloader.lock_bits=0x0F

atmega328bb.build.mcu=atmega328p
atmega328bb.build.f_cpu=8000000L
atmega328bb.build.core=arduino:arduino
atmega328bb.build.variant=arduino:standard