There is sometimes confustion among those new to HPSDR about exactly what hardware you need to be able to play with the system. This guide hopes to dispel some of this confusion and allow you to get up and going. Please note that availability is constantly changing, and while we try to keep this page as up to date as possible, things may have changed.
Description: Atlas is the main bus board for the OpenHPSDR system. it connects all of the components together and allows them to talk to one another. It also provides the connection for the power supply. Atlas has no real active components on it, merely some LEDs, connectors, capacitors and resistors.
Description: Ozymandias (or Ozy) is the board that connects the HPSDR boards to your PC or Mac. The current version of Ozy connects to your PC using USB 2.0. Future versions of Ozy will connect to your computer via Ethernet.
Availability: Ozymandias is no longer available in kit form. TAPR does have bare PC boards available on their [order page|http://www.tapr.org/kits_ozy.html] so that you can buy parts and assemble it yourself. The parts for Ozy are not difficult to get, and are available from Mouser and DigiKey, but assembly of the board will require some expertise in surface mount soldering. The pins of the Cyclone FPGA and FX2 are very small and require some dexterity and patience to assemble. A project called Magister is currently in pre-production to replace the Ozymandias until Ozy II is available. Magister will not be compatible with Janus, but this isn't necessary for a pure HPSDR system as described here. Magister should be available in assembled form from TAPR, please stay tuned for information about when it's going to be available.
Description: Mercury is the HPSDR receiver board. It has another Cyclone FPGA on it, and an Analog to Digital converter to receive signals via RF.
Description: Penelope is the HPSDR transmitter board. It has yet another Cyclone FPGA, and a Digital to Analog converter to generate the RF signal. Of course, if you only want a receiver, OpenHPSDR works fine without a Penelope.
Availability: Penelope is not available from TAPR currently in kit form or as a bare board. There is a commercial manufacturer of Penelope that is making boards under TAPR's Open Hardware License, Gerd, DJ8AY. His boards are being sold in the United States through eBay by the seller.
You need some way of providing power to the HPSDR components. You have a few choices here. Atlas is deigned with a PC-style ATX connector on it. An ATX power supply will work to get you going, although many of these supplies are going to be noisy and impart noise into your receiver. A high quality supply is reccommended for this reason. Alternatively, TAPR offers the LPU that will take a +12VDC signal and provide all the necessary voltages to the Atlas bus. The LPU is available from TAPR's order page.
These four boards should get you a functional HPSDR transceiver that will give you something to play with. That being said, there are optional components that may make your setup much more useful.
If you're looking for something pretty to put your setup in, the Atlas is designed to use the same spacing as PCI cards in a PC. This allows you to modify an ATX case to handle it such as is described on this Wiki in the The Antec P183 Solution page.
Alternatively, the project has designed the Pandora enclosure which has been intended to hold an Atlas bus with cards, the LPU and Alexiares. Pandora is currently available from TAPR's order page. There are also folks on the list making custom backplanes for Pandora with different mixes of OpenHPSDR boards.
Penelope only outputs .5 W, so unless you're really fond of QRP work, this isn't going to be enough for most people. To fill this need the project has designed the Pennywhistle board. Pennywhistle will be an RF amplifier designed to work with Penelope and output approximately 20W. This board is in the final stages of pre-production and will be available from TAPR soon. Pennywhistle will require some sort of low-pass filter between the output and your antenna to comply with regulations limiting harmonic emissions. See the next section about Alexiares for a possible solution.
In order to transmit a clean signal, and to provide some suppression of out-of-band signals into the receiver, a filter bank is useful. The project has designed Alexiares to serve this role. Alexiares is in pre-production right now and will be available from TAPR. There is a problem sourcing the torroids needed for the board, and it may be necessary for the hobbyist to wind these and solder them into an otherwise pre-assembled board.
As it stands, there are separate inputs into Mercury and Penelope for antennas. If you wish to share an antenna between transmit and receive, you will need a mechanism to do so. Gerd, DJ8AY, is providing a switching board that he is selling through the red_ella eBay seller. Also, Alexiares will provider transmit/receive switching on some of its antenna connectors.
This list of optional components is by no means exhaustive. There are many more cool components in the pipeline such as Excalibur. These are just the large components to get a "working" transceiver to get on the air. Of course, you will need a computer to run PowerSDR, KISS Konsole, or Ghpsdr.