Overview
The Genesis QR2S is a very strange transceiver. GenesisRadio is known for its excellent SDR radio kits. This radio is part SDR and part not. It is a crystal controlled 30M SDR receiver and a temperature compensated crystal controlled FM transmitter in one package (actually, on one circuit board). It is sold as a QRSS (ultra slow speed CW) transceiver, but there is no QRSS software designed to use the I/Q signals of a SDR receiver. ARGO, the recommended software, just uses one audio channel. You can run SDR software, like PowerSDR, but there is nothing much to listen to at 10.140 MHz (the 100 Hz wide 30M QRSS frequency band). Further, the two local oscillators of the receiver are not temperature controlled, so the received frequency wonders. That makes decoding of the QRSS signal difficult.
The transceiver has a PIC microcontroller. The user uses a PC to load the PIC with the pattern for transmission through a serial port. The single frequency receiver goes to the audio card of the PC. A software application (G-QR2S) selects among different QRSS-like modes: QRSS (they label it “CW”), FSK CW, DFCW, Hellschreiber and two simple frequency shifting patterns. The software includes an option to cycle through some or all the various modes. Once loaded, the transmitter can operate autonomously. Perhaps the biggest drawback is the lack of support for the WSPR mode. Software for incorporating WSPR is freely available on the Internet both for the PC programming and for the PIC. The QR2S serial port would be ideal for a GPS receiver to provide an accurate clock.
The kit has hundreds of parts, including one fine pitch surface mount IC. The instructions presume you are very experienced, to say the least. This is not a kit for the novice.
Kit construction
The kit arrived reasonably quickly from Australia. Every component is first quality. The printed circuit board is professionally designed and it has thick plating and clear silk screening. The resistors are metal film. Twenty-one 100uf bypass capacitors keep the power lines clean throughout the circuit board. Ample wire is supplied for the few inductors that need winding. Every part fits exactly in it holes. Unfortunately, my kit arrived missing all 15 transistors and 21 other parts. It also came with 9 parts not in the parts list. The kit, when complete, has 15 ICs, 15 transistors, 139 capacitors, 17 RF chokes, 117 resistors and other parts. The parts foul up was such a mess that it took about 2 hours to inventory and verify missing and excess parts.
The documentation for the kit has serious problems. You get a bill of materials, a schematic, parts layout drawings for the top and bottom of the circuit board, and a special layout drawing of the engineering changes. There is an Assembly Manual, but it is a disaster. It tries to walk the builder through steps, listing which components should be inserted during each step. It supplies photographs for some of the more crucial steps. It also provides some test procedures along the way. It might have been sufficient for an experienced builder. However, the Assembly Manual looks and feels like a draft that was written by three different people and was never made into a final document. The same procedure (adding multiple components of the same value) is described at the beginning by listing each component and its value separately, later by listing the components of the same values together, then later by yet a different nomenclature (e.g., 4 x 10K). Some of the photographs are essential and superb, but some are clearly outdated. One photograph shows a surface mount capacitor in the photo that the instructions clearly say to omit. The crystal filter instruction urgently explains to not use the unmarked 8 MHz crystal, but all 8 MHz crystals were marked. In a number of places the instructions ask you to install a component that was already installed. In a particularly confusing spot, the part number does not match the value, that number has already been installed, and no part matches the value listed. There are numerous other typos.
Making it work
The beginning of the Assembly Manual recommends that you join the on-line Yahoo GenesisRadio group. I would recommend the same. Bat and Nick are the software and hardware engineers that support builders. They are deeply knowledgeable and work tirelessly to help you get your radio working. They quickly sent me the missing parts, even though they were somewhat incredulous that such a large mistake on their part was possible.
I am a very experienced ham, engineer and builder. Most of the radio was assembled in the first week, but it took another two weeks to get replacement parts and straighten out all the inconsistencies in the documentation. The receiver came to life after putting in the last component. The transmitter worked, but could not be placed properly on frequency. (It has to be below 10,140,000 Hz, but not more than about 50 Hz below.) I spent a week going back and forth with the designers on the Yahoo group. I removed components, checked them with meters, and replaced transistors until I was blue in the face. Finally, I noticed that one of the engineering changes was documented wrong. It was a tiny, but critical mistake in the drawing. I changed the capacitor location and everything worked. I emailed a detailed description of the error to the company. They immediately published a “revised” drawing on the Yahoo site, but the revised version had the same error!
Performance
If you don’t know how to measure radio frequency signals to 1 Hz accuracy, you are in for an education. Properly adjusting this radio requires a stable receiver and/or some laboratory grade equipment. I used a contest class transceiver (with stable oscillator), WWV, ARGO software, and some older laboratory instrumentation to get the transmitter and receiver spot on. The transmitter is very stable because of its temperature feedback crystal heater. If you care about the frequency shift range (for modes like DFCW), that will be difficult to adjust accurately. It matters more for a mode like WSPR. As noted above, the receiver wonders over a 5+ Hz range every few minutes in my temperature regulated workshop. Thus, it produces an annoying drift of QRSS signals. The receiver is otherwise excellent, albeit overdesigned for QRSS operation.
The transmitter output of my radio did not achieve specs. The output is rated at 1.5W and I could not even get 1W out. The designers recommend that I squeeze the coil windings on the low pass filter to raise the power out. By squeezing the windings very tightly, I could get 1W showing on my WM-2 QRP wattmeter. However, I realize that de-tuning your low pass filter gets you more power by increasing the harmonics, not by improving the fundamental. Duh. Since the output is single-ended, the second harmonic is the largest. (Push-pull amplifiers cancel the second harmonic, which lowers that demands on the low pass filter.) With the coils squeezed I see the second harmonic about 50 dB below the fundamental. Third and forth harmonics are about 60 dB down.
Rating
This is a very interesting radio. It is a very stable transmitter, essential for QRSS and its relatives. The receiver is excellent, perhaps overdesigned, but is not as frequency stable as I would like. The bandwidth is sufficient to tolerate the instability. The quality of the materials is first rate. The problem is the documentation. Given that this is not an easy kit to assemble in the first place, one might expect more attention to the documentation. Had the documentation been much better, I would have rated this kit much higher. In spite of claims to the contrary, the designers at GenesisRadio were unaware of key flaws in the documentation that make this kit nearly impossible to build properly. Perhaps GenesisRadio will spend the time necessary to revamp the documentation. Until then, a rating of 3 reflects my overall assessment.
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