The Hermes-Lite Project
The Hermes-Lite project aims to design and market a software defined radio transceiver
that directly samples the antenna
with an analog to digital converter, is completely controlled by Ethernet, and costs about USD 200.
It is contained on a single 10x10 cm PCB. The standard enclosure is 10x15 cm and the extra space is meant for filters,
transverters and other add-on boards. The Version 2 hardware includes a 5 watt push pull MOSFET amp as well as a 100 mW low power output.
Since the FPGA and the digital up/down conversion is on-board, a sound card is not used for radio samples, and is only used
for the microphone and for playing radio sound.
Filter Board by James Ahlstrom, N2ADR
The Hermes-Lite 2 is ready to use at 100 mW output or at 5 watts output as an exciter for a subsequent RF amplifier. But to use the 5 watt amp
as a complete QRP rig, it needs transmit low pass filters. I designed a 5x10 cm filter board that clips to the main board
and fits into the standard enclosure. It has transmit low pass filters for 160 to 10 meters, and a 3 MHz high pass filter for receive.
The filter board is automatically controlled by the Hermes-Lite main board. The filter is currently being tested, so is not yet available.
Here you can see a photo of the board, and the schematic.
January 2, 2018. More to follow...