Hermes - A DUC/DDC Transceiver
Project Leader: Kevin M0KHZ
Update 11 July 2012
Hermes is a single board Digital Up and Down Conversion (DUC/DDC) full duplex HF + 6m multi-mode transceiver.
Hermes has the following features and facilities:
- Continuous, uninterrupted, receive coverage from 10KHz to 55MHz.
- Supports Real-Time display of entire sectrum from 0-55mHz (with suitable PC software)
- Supports 7 fully independent receivers (sharing the same antenna - and with suitable PC software)
- Each receiver can display 48/96/192kHz of spectrum
- Blocking Dynamic Range (ARRL Method) no detectable gain compression below ADC overload
- Transmit and receiver image rejection > 110dB
- Full duplex operation, any split over entire 160m to 6m range.
- Transmitter two-tone 3rd order IMD of -50dBc on 20m @ 400mW output
- 500mW RF output on 160 – 10m amateur bands, 350mW on 6m
- Built-in high performance preamp, with a noise floor typically -135dBm in 500Hz
- Software-selectable 31dB input attenuator in 1dB steps
- High performance receiver – same specifications as the HPSDR Mercury receiver (ie Dynamic Range typically 125dB)
- FPGA code can be updated via the Industry Standard TCP/IP network Ethernet connection
- Seven user-configurable open-collector outputs, independently selectable per band and Tx/Rx (for relay control, etc - with sequencing via PC code)
- Separate open-collector PTT connection for amplifier control, etc, with sequencer
- Microphone PTT jumper-selectable from tip or ring connection
- Bias for electret microphones via jumper
- Four user-configurable 12 bit analogue inputs (for ALC, SWR etc)
- Three user-configurable digital inputs (for linear amplifier over temperature, etc)
- Can operate from a 13.8v DC supply or +12v and +5v supplies
- Jumper selected in-built low noise and high efficiency switch mode power supply designed by Kjell Karson,LA2NI – less than 600mA (receive - one receiver) from a 13.8V supply
- I2C bus connector for control of external equipment
- Full QSK operation (performance dependant on associated PC and control software)
- Low-level transmitter output for transverter use via user-selectable output attenuator
- Stereo audio outputs at line and headphone levels
- In-built 1W stereo audio amplifier for directly driving speakers
- Direct, de-bounced connections for a Morse key (straight or iambic) and PTT
- Low phase noise (-140dBc/Hz @ 1kHz at 14MHz) 122.88MHz master clock,which can be phase-locked to an internal 10MHz TCXO or external frequency
- Direct ribbon cable interface to Apollo 15W power amplifier, low pass filters and automatic ATU
- Industry Standard TCP/IP network Ethernet interface supports static, APIPA or DHCP IP address
- Hermes responds to ping and ARP requests and auto senses network connection speed
Apollo is a combined 15w PA, Low Pass Filter bank and Automatic ATU. The Apollo project is led by Kjell Karlsen LA2NI.
Update 7 August 2011
Update 7 July 2011
A prototype board has been built and tested. The board is fully functional and meets or exceeds the performance of the Mercury/Penelope/Metis/Excalibur boards the design is based on.
Some minor board layout issues are currently being addressed and a pre-production layout is presently being prepared. The KD5TFD and W5WC versions of PowerSDR(TM) as well as KISS Konsole have been modified to provide native Hermes support.
Ken, N9VV, has a lot of information regarding Hermes on his web site here http://www.n9vv.com/hamradio.html