比较QS1R的当前可用的竞争：http://amfone.net/Amforum/index.php?topic=22878.0
The RFSpace SDR-14 is ~$1100 and covers up to 30 MHz. The SDR-IQ is ~$500 and also covers up to 30 MHz. Both receivers are inferior in dynamic range and image rejection to the QS1R and Perseus because they use an Analog Devices AD6620 DDC instead of a FPGA based DDC. The AD6620 was developed for the cell phone base station market and provides only limited dynamic range and filtering options. Both the SDR-14 and SDR-IQ use a USB interface that limits the speed the IQ data can be sent to the PC - this limits the real time bandwidth that they can display. The new SDR-IP is $3000 and covers to 34 MHz. Instead of USB it has a 100 BaseT Ethernet interface to the PC. The interface IC they appear to use is the Wiznet W5300 <http://www.wiznet.co.kr/en/pro02.php?&ss[2]=1&page=1&num=26>. When this chip was first available I evaluated a sample and was able to achieve transfer rates of about 8 MBytes/sec. RFSpace is stating they need 64 Mbits/sec for the top bandwidth of the SDR-IP, so 8 MBytes/sec (= 64 Mbits\sec) seems about right. The QS1R is able to transfer ~32 MBytes/sec over it's high speed USB 2.0 interface and it covers to 60 MHz instead of the 30 and 34 MHz coverage of the SDR-14/IQ and SDR-IP. The QS1R is $1000.
The Microtelecom Perseus is ~$1200 in the US and covers up to 40 MHz. The Perseus is superior in dynamic range and image rejection as well as sensitivity to the RFSpace SDR-14 and SDR-IQ. It uses the same high speed USB 2.0 interface as the QS1R does. The Perseus uses a smaller FPGA (where the DDC function is) than the QS1R. The large FPGA and the open source nature of the QS1R has allowed expanded applications such as Skimmer Server (part of the CW Skimmer package) written by Alex, VE3NEA where he has implemented 7 independent receivers in the QS1R with selectable bandwidths of 192, 96, or 48 kHz. Many Perseus uses have reported that they still need an external preamp for use on 10 meters even though Perseus has it's own built in preamp. The QS1R allows you to bypass the internal Low Pass Filter and add your own external Band Pass Filter and low noise pre-amps for coverage in under-sampling mode up to 500 MHz directly. The SDRMAX-II software supports using the QS1R in under-sampling mode. The QS1R has an on board DAC for audio output - this results in much lower latency (important for CW and use with a transmitter) than Perseus which uses the computer's sound card for output. The QS1R covers 6 meters, the Perseus does not.
