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Showing posts from 2007

QS1R Rev B Picture and new Yahoo group

History of HPSDR Mercury and Quick Silver

History of HPSDR Mercury and Quick SilverPhilip Covington, N8VBEarly HPSDR and XYLOIn 2005 I started a High Performance SDR (HPSDR) project which was to consist of a motherboard carrying a FPGA/USB 2.0 interface and power supply with the provision for plug in modules through 40 pin headers.I had planned a narrow band high dynamic range module based on a QSD/DDS/PCM4202 audio ADC and a wide bandwidth module based on a high speed 16 bit ADC: soon selected the LTC2208 ADC from Linear Technology.A representative from Linear Technology came across my blog ( ) and offered evaluation boards and samples to support the project.At about the same time my HPSDR project came about, Phil Harman, VK6APH and Bill Tracey, KD5TFD were interested developing a sound card replacement to be used with the SDR-1000 and had started develo…

QS1RT Soldered


(Click on picture above to see larger version)

Boards were received 07-20-2004


QS1RT VERB (VErsatile Radio Board) Project:

(Click on picture above for a larger version)

ADC: Linear Technology LTC2208
DAC: Analog Devices AD9744
FPGA: Altera EP3C25-QFP240 Cyclone III
CPLD: Altera EMP240-QFP100 MAX II
USB: Cypress CY7C68013A FX2
EEPROM: Microchip 24C128

Internal encode clock is 125 MHz.Board interface is through:USB 2.0 or,
Optic Fiber SFP Module at 2.5 Gbps or,
Copper Cat6 cable at 2.5 Gbps.TI CODEC provides 48/96kHz audio in and audio outFPGA can be programmed via USB or Fiber/Copper interface in Fast Parallel Programming mode (byte wide transfers per clock cycle).JTAG interface for FPGA and CPLDConnectors:ADC INDAC OUTEXT ENCODE INMIC INL&R AMPLIFIED AUDIO OUTL&R LINE INL&R LINE OUTDC POWER INJTAGUSB 2.0RJ45 (2.5 Gbps serial over copper)SFP (2.5 Gbps serial over fiber)TTL Level Serial from FX2SPI and I2C to RF external RF boardStatus: Prototype boards are scheduled to arr…

QS1RT Prototype 06272007


Please click on the image to see a larger version.

TI PCM4222 ADC Now Available


TI's 24 bit, 216 kHz, 2 channel ADC is now available. 122 dB dynamic range is claimed. The part comes in a 48 pin TQFP package. It is available from Digi-Key in single quantities at $22.42 each.

Here is the link: PCM4222

This is a FFT plot of the PCM4222 at 192 kHz with no input:

The rise in amplitude at about 65 kHz is a concern, but for SDR use a bandwidth of 130 kHz would still be useful.

The PCM4222 is definitely easier to get in single quantities for experimenters than the AKM AK5394 is, but the AKM chip is still probably the winner.

Quickfilter QF1D512


Here is a link to useful FIR engine chip:

They offer a DIP version for experimentation:

Mouser stocks the parts.


The current status is that I am working on integrating the QF1D512 part into the QS1R receiver prototype. I have no new projected availability for QS1R. In fact it appears that interest may be somewhat limited - enough so that it would not be worthwhile to offer assembled units. In that case the design files will be posted from anyone who wants to build a board.

QS1R Block Diagrams & Software news

QS1R Diagrams Posted:

Architecture - PDF diagram of QS1R overall architecture

RF Front End - PDF diagram of QS1R RF Front End

Supporting Software:

QS1R/QS1T supporting software will be an open source application called QSRunner. It will support both Windows and Linux. In addition to supporting QS1R/QS1T, QSRunner will also support the SoftRock and HPSDR JANUS-OZY/MERCURY projects.