Difference between revisions of "HERMES"

Revision as of 09:57, 9 October 2009

Hermes - A DUC/DDC Transceiver

Hardware block diagram. Click to enlarge.

Project Leader: Kevin M0KHZ

Following the outstanding success of Mercury and Penelope, and while investigating the verilog code for both, I had the insane idea of merging the verilog code of Mercury and Penelope into a single fpga! I played around with this idea for a while and the more I thought about it the more I liked the idea.

So here is the proposal, to develop a single board HPSDR based on the hardware of Mercury and Penelope and a single large fpga.

This board would have PC connectivity by USB. I’m planning to squeeze this all onto Euro Card sized PCB (100 x 160 mm), and if I utilize both sides I might even have room for a Pennywhistle type PA  :).

Basic specs so far (nothing cast in stone)

• Fpga EP3C25Q240C or EP3C40Q240 (I think this is the largest without BGA pin out)
• Mercury receive chain
• Penelope transmit chain, possible small change to gain distribution
• USB2 to PC data transfer
• Pennywhistle PA (if there’s room)
• 10Mhz ext an option
• Alex filter switching header
• 2.8W stereo audio PA
• 13.5V supply

Following the tradition of the HPSDR naming convention, I thought Hermes was appropriate as he was known for his invention and theft!

The enclosure I intend to use for the prototype, the euro card will slide in, regulators and PA transistors will be bolted directly to the case and there is plenty of room for additional hardware (LPF's, Beagleboard??? - who knows :))

Current status ( 20 April 09 ), Project proposal open for comment. Looking to nail ‘major’ hardware decisions by the end of the month. Initial draft schematics will then be produced and placed here on the Wiki for comment.

Update (13 September 09) the initial schematics have been created and can be found here : Hermes_RevA5-3.pdf

Update (27 September 09) following comments regarding the initial schematics, the design has now been frozen for Alpha board development, thank you to all who have contributed, through an HPSDR community effort, Hermes is one step closer to becoming a reality. The updated schematics can be found here : Hermes_RevA7-3.pdf

Update (9 October 09) Just to wet your appetite, here are the current top & bottom layout details for Hermes.

Hermes_top.pdf

Hermes_bottom.pdf

Although not quite finished you can gain an appreciation of the beautiful and artful skills from Tony. He is doing a fantastic job laying out the 6 layers needed to bring Hermes alive, current plans are to finalise the layout this weekend, shortly followed by an order for the Alpha PCB’s.

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

Please see HERMES - Design Discussions