(Images from both vendor's websites) This radio set, the CS Series, is the follow on the earlier KN-Q7A radio. It is a SSB only rig. The radio is sold as a kit from China (http://www.crkits.com/) with a US dealer in Idaho, QRVTronics (QRVTronics.com, HAM Radio Kits, KN-Q7A Kit, QRP Kits, CS-Series Kits). It will take some time to assemble, but all parts are thru-hole and the manual well written, laid out and illustrated. Nearly as good as the old Heathkit assembly manuals. (see assembly manual http://www.crkits.com/csmanual.zip) This is a ziped manual. Unzip inside of it's own folder. If you deal with Adam @ CRKits in China, you will likely have something of a wait for your shipment. Adam is a full-time worker with this kit as as a sideline. Larry @ QRVtronics , based in Sugar City, ID, ships quickly and via USPS - as an Alaska resident, this is something near and dear to me - not getting gouged on shipping. Larry will also build and tune the rig for you at a very reasonable price point. In an unusual move for small radio vendors in China, Adam has a full documentation set, to include a schematic, all IN ENGLISH, available on line ( see http://www.crkits.com/csmanual.zip) . This manual is a work from many hams in the QRP community and is well done. The full documentation was also the reason I went ahead and sent my boxtops off the Larry for the radio. Here is where it gets interesting. The CS series is the KN-Q7A with a full band coverage digital VFO. The CRKits version is a single band. You can pick 80, 40, 20, 17 or 15 meter bands. Output on 80 and 40 meters is at least 10 watts, so this is - by Amateur Radio Service convention, not considered a "QRP" radio. Output on 20 M is 5 Watts, on 17 M - 4 watts and on 15 M is is around 2 watts. The QRVTronuics versions is available as a dual band kit, pick any two. Optional frequencies are: Base Radio (40 Meters) plus 80 Meters. Base Radio (80 Meters) plus 40 Meters Base Radio (40 Meters) plus 20 Meters Base Radio (20 Meters) plus 40 Meters Base Radio (20 Meters) plus 15 Meters After several experiments, If you want 40 and 20 Meters, it is best to build the 20 Meter and add 40 Meters In kit form - you get a filter assembly that allows use the second band. Now, here the cool part - The VFO is controlled by an Arduino microprocessor and the code in also posed to the CRKits site. A full VFO kits and loader can be had from either vendor. The Arduino is supported by the IDE programming environment and this software set can be had on line for free - part of the Arduino community. A very open bunch. The software sketch (processor code) is also found on line at the CR kits site for you to download. . Larry will load the dual band code in the processor for the setup you pick if you go with the dual band setup. I'm working with Larry to get a copy of the sketch (Arduino code) to allow modification for RX of WWV at 10 and 15 Mhz) This will be posted o the QRVtronics site when completed. Since the summer is a busy time for me, I ordered an assembled 20/40 meter rig as these are the best pick fro my area. For the L48. the 40/80 Meter might be a better pick for NVIS type communication paths. Larry kept me informed of the build progress and shipment via a tracked USPS package. This is a compact radio set that uses a speaker/microphone. This radio, as do many of these kits, lacks an AGC loop, so headphone use is not a good idea. This is where the speaker/mike shines. The additional filter fits above the main board. The case, solid metal, has a slot to hold the board. Edward, KJ4FGI, hos posted a video of the KN-Q7A version in operation. The CS version is identical, other than the full range digital VFO. large digital display before mounting. The radio is a common NE602/LM386 kind of setup. The final PA is a IRF-510, which is noted for being more tolerant of high SWR at the antenna. The radio has a reverse polarity protection diode as well. The vendor shows these specifications: . Dimension: 153 mm x 97 mm x 40 mm, not including connectors and knobs 6.0 x 3.75 x 2.0 inches including feet . Weight assembled: 12 oz, not including microphone The dual band version is slightly heavier. . Power Supply: 12 to 13.8 V, 3 A . Current consumption: 70 mA in RX and about 2 A in TX @ 13.8 V . RF output: about 5-10 W PEP @ 13.8 V typical . RF output for 15, 17 and 20 Meters will be between 1 and 5 watts typically . Sandwich digital VFO integrated with the LED hole pre-drilled . Innovative one LED frequency display . Stable and accurate frequency like a crystal . Both USB and LSB are be supported by changing BFO frequency in calibration mode . Sensitivity: about 0.5 uV at 10 dB SNR . UNBAL jumper added to intentionally break the balance of NE602 to allow more convenient TX power peak alignment and antenna tuning . Low dropout diode is used to allow a bit more battery life . Final power amplifier changed to IRF510 and minor change in LPF circuit . Speaker microphone added to the standard configuration . IF filter: 6 pole crystal ladder filter + 1 pole post IF amplifier crystal filter . IF bandwidth: about 2.0 KHz . IF frequency: 8.467 MHz . Connectors: Speaker, Microphone and Antenna . Antenna Connector is: BNC type Larry also offers a digital display mod for his kits at a small additional cost. I went with this as well. My early bench testing showed that full band overage and power output specs were easily met on my rig. NOTE - power output is input voltage dependent. On my 8xAA NiMH battery pack, power was 8 watts on 40M and just under 4 watts on 20M. On a fully charged AGM battery, full power was no problem. Why would you all care? This radio, and a small Near Vertical Incidental Skywave (NVIS) antenna should give you reliable comms on 80 or 40 meters, pretty much all day, within ~300 miles of your location. At least a General class Amateur Radio Service license is required to operate this legally. Coupled with low weight, simple controls and decent power on 80/40M (10 watts) this radio is in a niche by itself... Total cost, with shipping and assembled for the dual band with digital display radio is under $300. My wife gets unhappy if I carry my KX2 outside to anything other than the RV, and I agree. This rig is solid, simple and low cost enough to to bush bash with at little risk. Have fun, stay safe.
You know this is a very economically way to get into it. I would be interested to have it just to listen since it appears I am too damn lazy to get my Extra rating, started studying twice and it fell apart due to many reasons...or excuses. I know this is strange because I was a communication tech/engineer most life but worked mostly the wideband stuff (satellite and microwave). Anyway, recently I have thought of getting something inexpensive just to listen and perhaps grow my interest. I do have my General license and someday, when perhaps I can finally get a grip on this place and can enjoy some hobbies of interest, I will get my Extra. Yes, I might look into this. Thanks!
The kit, single band w/speak mike, is $125. I don't think you'll find a low power SSB rig this inexpensive anywhere else. Oh, with full documentation. I assume you have problem soldering, the part layout isn't as tight as seen in many other kits. Even cheaper would be to track down a KN-Q7A and retrofit the digital vfo for ease of tuning and full band coverage. The original rig only covered a few KHz owing to a 'rubbered' crystal VFO Since these have full band coverage you General ticket is more than good. I'm pretty enthusiastic- but then I bought one. Pretty easy platform to hack as well,. I'm trying to get the VFO sketch to modify for wide-band coverage.
if all you're interested in doing is listening, even if only for now, a shortwave radio with BFO for SSB reception is less expensive. Put up a wire antenna for it. Transmitting with low power is even more specialized a hobby than just ham radio in general, not many people would recommend using it as your first or only transmitter.
I have the software modified, now just waiting for my serial loader to show up in the mail Should be a fun piece of gear to hack on.
