High Performance Software Defined Radio


H P S D R

Atlas - the backplane


The Atlas is a passive backplane that all other modules plug into. The circuit board has provision for up to six DIN41612 connectors at 0.8 inch spacing. An ATX 20 pin power connector is fitted to the board so that 12v, 5v, 3.3v etc. supplies from a standard PC power supply can be used for power.



OZYmandias - interface module


The OZY module is an FPGA based interface controller card that provides the input and output connections to the real world. The use of an Altera Cyclone II FPGA provides numerous control lines for interfacing the various boards connected to the Atlas backplane.




Penelope - HF 1/2-watt Exciter


Penelope (DUCk) 1/2-watt transmitter/exciter board will be a good companion to the Mercury HF direct sampling receiver board.

The Atlas (bus) compatible Penelope transmitter will use Digital Up Conversion (DUC) techniques and process the I and Q signal from the PC (or Sasquatch DSP board) directly without the need for a sound card.




Mercury - a direct sampling front end


Perhaps the most exciting of all the modules, the Mercury module will enable direct sampling of the 0-65 MHz spectrum. Based on a Linear Technology LTC2208 130MSPS 16-bit A/D converter, the board will contain it's own FPGA to undertake Digital Down Conversion (DDC) to 250 kSPS or less for transfer over the Atlas bus to the USB interface on the OZY board.



Performance figures are as follows:

ADC overload (preamp on ) -12dBm (preamp off) +8dBm

MDS (500Hz) all bands 160m - 6m = -138dBm (preamp on) - 118dBm (preamp off)

MDS (500Hz) 6m via Alex preamp = -146dBm

IP3 equivalent = +33dBm (preamp on) >50dBm (preamp off) The IP3 is independent of tone spacing.

Blocking Dynamic Range 119dB

Blocking Dynamic Range was measured at 100kHz and 5 kHz for 1dB gain compression with similar results. The DBR is set by the overload point of the ADC rather than being phase noise limited.

122.88MHz clock phase noise -149dBc/Hz at 1kHz spacing.


Excalibur 10 MHz Reference Injector card


Excalibur is a small accessory card for the Atlas bus that enables the use of an external 10 MHz frequency reference for locking the frequency of an HPSDR radio to the same accuracy of the standard, or GPS disciplined oscillator.





PennyWhistle - 20 Watt Power Amplifier



PennyWhistle is a compact RF power amplifier stage that can be used with Penelope and Alex to make a complete 16 to 20 Watt transmitter. The output stage is a single stage amplifier that uses a pair of TO-220  16 Watt Mitsubishi RD16 parts in push pull and has approximately 19 dB gain, depending where you bias it, so it will deliver 16 to 20 watts output with 1/4 watt drive

Alexiares (Alex) - RF Bandpass Filters

Alexiares (or Alex for short) is a set of RF Bandpass filters for use with Mercury or any other SDR.


Connection of the boards without PA and Excalibur.





My HPSDR is now UP and Running since 04. 2009 with a great performance. It is a pleasure to work with the HPSDR.

I use PennyWhistle. With this ORP PA with 15 Watt output connected to a second 50 Volt Mos Fet PA with 4 times BLW 95 I`am able to generate around 500 Watt with the HPSDR with a very nic and clean signal.

Further information under the following link..


HPSDR Website; You can access information on all HPSDR Projects Here

HPSDR eMail List




Look insite the HPSDR Box



Look insite the HPSDR Box




Front view of the HPSDR




Rear view of the HPSDR



Front view with Flex 5000 and HPSDR




If you want to hear HPSDR signals go to 3.713 Mhz !!