Another "Sermon on the Mount" for QS1R by Phil N8VB

Phil's forward looking prospectus for the QS1R.
Velly intellesting.

Is this fitting in your read window? I can break it up or change formats. -Rick

Quoted from Yahoo users group today, Feb 1, 2010
after being question at to the future of the product.
Note: I am a QS1R owner, Rev. C. and have had tons of fun with it.

"Re: [qs1r] WhereZit all going?

Hello,

The official software for use with the SRL-LLC QS1R receiver is SDRMAX-II. You do not have to compile SDRMAX-II - it is downloadable from the website as a single file installer. The procedure to get QS1R up and running is almost exactly the same as getting hardware from RFSpace or Microtelecom Perseus up and running. You download the software, install the software using the installer program, plug in the QS1R hardware and install the driver when prompted to do so. That's it. SDRMAX-II is developed and maintained by SRL-LLC.

The SDRMAX-III GUI was developed by a QS1R user as an open source program. I developed the QS1RServer that is paired with SDRMAX-III - the QS1R user wrote the GUI. This developer has moved on to other projects but source code for SDRMAX-III is available in SVN for anyone to use, modify, enhance, etc... Since SDRMAX-III is not the official QS1R software package, it is not distributed with an installation program. It is available in the archives as a binary executable on the Windows platform. SDRMAX-III must be compiled for use on Linux or OSX making sure the prerequisite libraries are available and installed.

The QS1R receiver and software is no more "experimental" than the offerings from RFSpace or Microtelecom (Perseus). If by "experimental" you mean open source and promotes experimentation, then yes, even the official SDRMAX-II software is "experimental" - you can download it, modify it, make enhancements, and extend it under the terms of the open source license. In fact, not only is the software open source, so is the firmware for the QS1R's microcontroller and the Verilog HDL for the DDC implemented in the QS1R's FPGA. However, you do not have to compile these items or to install a development environment to install or use the SDRMAX-II software - everything is taken care of by the software's installer. You do not have to be a programmer or RF engineer to use and enjoy the QS1R any more than you have to be a programmer or RF engineer to enjoy and use the Perseus or RFSpace products.

The SDRMAX-II software has many features not found in the current software for other similar SDRs, such as the ability to do remote, ability to adjust to various screen sizes and resolutions, innovative tunning methods within the panadapter and waterfall, direct DAC audio output for low latency, etc... The next release of the software this year will have many enhancements including recording ability for up to 2 MHz wide bandwidth.

Consider that if RFSpace or Microtelecom goes out of business, you are more than likely stuck with the last software version that was available at the time because their software and firmware is proprietary and closed source. If SRL-LLC goes out of business, you can (if you are capable) continue to develop the software or find a programmer who is willing to do so for you. All QS1R owners can get the hardware schematic for the QS1R after purchasing free of charge. I don't think getting the schematic to the RFSpace products or Perseus is an option under any circumstances. SRL-LLC will be around for many years to come, supporting it's hardware and developing new hardware and software - we have no plans to go out of business!.

Comparing the QS1R to the currently available competition:

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.

This is not an all inclusive or extensive list of differences. There are other differences between manufacturers that you can research further.

Phil N8VB

On Mon, Feb 1, 2010 at 12:15 AM, n612dw <n612dw@...> wrote:

Hi All,
New to the group, would like some feedback.

I am considering taking a serious plunge into the SDR world with something more useful than the SoftRock SDR kits I have built. There serious contenders appears to be those in the HPSDR, the RFSpace, Perseus, and QuickSilver camps. Been a ham for many years, and my interests are varied from HF to S-band. SDR is here to stay and obviously is the future of radio.

While the hardware of the QS1R certainly is very attractive technically (particularly the potential given the FPGA employed for futures), without great software on the "radio" side it will likely never get out of the "experimenters" playland. Dont get me wrong, enjoy experimenting as much as anyone on this forum, and I probably generate more soldersmoke than most. But, I do this stuff all day as a profession (both hw and sw) and don't really want to spend all my personal radio time always fiddling with inconsistently supported software/hardware.

While I could certainly grab a copy of this stuff on the SVN tree and build it myself, this is not what I really want to do when I get home and simply want to listen on the bands with this platform.

I am a bit concerned about spending a considerable amount of buckage for something that seems to some extent is still an experimenters dream rather than a real commercially viable product for general use. I do not see very much with respect to recent accomplishments on QS1R or possibly even more important (given the core of QS1R is stable) - its companion software, SDRMAXIII, for months. Most of the forum seems dominated with "how do I get this or that working" type of threads, suggesting relative immaturity of the baseline. I do not want to make this investment and then having it all orphaned off and it becoming a Frisbee.

After downloading SDRMAXIII and playing a bit with it (but not able to actually connect to a server), it appears to have huge potential but it seems to be orphaned off and has been effectively abandoned since the primary developer left the project 6 months ago. Where is this going? Is there any coordinated effort to move it forward towards its potential?

Or is it going to suffer the fate of so many open source projects with a hundred different nodes on SVN where nobody knows what is where and for what after the initial shine wears off, going off in all directions? Phil has done a great job on the hardware, but without great appl software, it will always be a toy.

What is the future and what are the commitments for both? What are the timelines?

Is there any organization behind the SDRMAXIII software development that at least can assemble a consistent set of requirements – or will it always just be a platform out there that one has to build their own binaries to enjoy it? Is it already falling off into the orphanage?

Selfishly speaking, I'm mostly interested in a very good receiving platform in HF and as an IF strip for other activities higher up. Having many means for xmitting already, my own view is that I would have little interest in the QS1T strip. Would rather have the rx front end stuff done and in particular have SDRMAXIII carried forward to realize its potential so that the two become "plug and play" and spend the experimental effort further downstream of the IF strip.

If there is no intent to move to having commonly available binary installations for at least Windows and Linux (which QT support nicely) platforms, I probably will simply to go to RFSpace/Perseus.

While I may be willing to build my own binaries (and possibly contribute), I don't want to invest in something where that is the only path to successfully using the hardware. At some point, all I need is a path to a webpage to download an installation package and plug it into a new computer, and turn it on.

Anyone have a server out there that I could connect the .21 version of SDRMAXIII to ? Is there a list somewhere?

73's,

-bob