Difference between revisions of "HERMES"

Revision as of 13:09, 11 December 2012

Hermes - A DUC/DDC Transceiver

Hardware block diagram. Click to enlarge.

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.

It is basically the Mercury, Pennylane, Metis and Excalibur (less TCXO) boards rolled into one PCB. The board communicates to an associated PC via 100T/1000T Ethernet.

Hermes has the following features and facilities:

• Continuous, uninterrupted, receive coverage from 10kHz to 55MHz.
• Supports Real-Time display of entire spectrum 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
• High performance receiver – same specifications as the HPSDR Mercury receiver (ie Dynamic Range typically 125dB)
• 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
• 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 reference
• Direct ribbon cable interface to Apollo 15W power amplifier, low pass filters and automatic ATU or ANAN-10 10W power amplifier and low power filters http://www.apache-labs.com
• 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
• PCB is 160mm x 120mm, 8 layers

Apollo is a combined 15w PA, Low Pass Filter bank and Automatic ATU. The Apollo project is led by Kjell Karlsen LA2NI.

Hermes can be used as a Vector Network Analyzer: VNA

Hermes and Apollo in enclosure - photo copyright Kjell Karlsen 2010.

Update 7 August 2011

The primary PCB layout team member of Hermes, Abhi has a blog on Hermes at http://hpsdrhermes.blogspot.com/ . --KV0S, Dave

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

(click for larger image) photo courtesy Abhi Arunoday

There are also the Hermes Board Build Notes

Update 2 December 2012

A useful website for Hermes users can be found at www.k9ivb.net/hermes/ by Dick K9IVB. --KV0S, Dave