Sunday, 1 November 2015
Well I waited so long for an Elecraft K3S review, I decided they couldn't be that much better than the original K3. No one and I mean no one to date has done a side by side comparison. I therefore decided to take a look at what all the fuss was about concerning the flex signature series of radios. I wanted to put a toe in the water to decide whether it was right for me, so decided against the 6500/6700 in favour of the more economical 6300. This transceiver uses a lower direct sampling rate at the ADCs, can only show 7MHz of band at a time, only has 1 spectral capture unit, only has 2 rx slices available, doesn't have an rx preselector, only goes up to 50MHz, doesn't have a split rx/tx transverter interface etc etc etc. Despite all this, I decided on the 6300 and took the plunge. I decided on Flexradio (rather than Apache labs) because they did the hardware, the firmware and the software, so if there were any problems with the radio there would be no dubiety about whose fault it was. Just before purchasing the radio I did ask the sales rep for Flexradio where they where going next in terms of hardware, his response was that the Xilinx Virtex 6 FPGA was state of the art and that this hardware would be be 'it' for Flexradio for the foreseeable future. If it were me I'd be looking at Virtex 7 Zync, with embedded dual core arm A9 processors, but if you believe the sales guy, this isn't on the horizon. I was worried that Flex would sell the usual 10,000 units then drop it like a hot potato by moving onto the next hardware platform kinda like they did with the 1500/3000/5000. The old series of radios were problematic due to the majority of the processing being left to your desktop processor (as per Apache labs). This meant that things would fall over for reasons only the desk top processor would know and if it could speak it would tell you that it decided it was a good time to go check the hard drive for viruses or update the operating system during CQWW....oooops! The new series of flex radios does front end processing in a dedicated FPGA to take the heavy lifting off the desktop PC. This now means you can have multiple apps running and there is enough overhead for it to decide to do housekeeping without motor boating your tx audio and falling over. The downside to all this is that if you buy, you are in the keep net, forever reliant on the good nature of Flexradio systems to develop extra software bells or whistles out the goodness of their heart. If you had decided to buy Apache Labs, the software would be being developed in the open community and would grow 'forever'. However it will be a while before anyone realises that the flex software (SSDR) isn't going to be developed forever as they are still trying to fix all the problems with the original bells and whistles (my findings are that Flex have a particular power line noise in the US that the NB can handle and apart from that is of no help what so ever, Elecraft (and every other manufacturer) rip them a new one in that department). IMHO basically no 'toys' in SSDR work as well as any conventional desk top radio. The purchasing experience so far: 1) Radio arrives direct from the factory, bottom metal panel covered in greasy finger prints, top panel had rubber feet marks from something that had been stacked on top of it. 2) Power led diffusing coating had score across it meaning it was unevenly lit up to annoy me every time I power the radio on. 3) 4 interior screws missing meaning that the band pass filter board became disconnected from the main PC board in transit. The radio powered on despite this and no fault indication was given to the user. No BIT? The only clue was that the antenna selection mechanism wasn't working. Flexradio support was "Do a hardware reset and if that doesn't fix it, return it" very helpful! 4) The FPGA firmware currently isn't stable with all 6300s. The firmware engineers have certain internal interfaces to the FPGA on a timing knife edge meaning that due the manufacturing variations in process, voltage and temperature some 6300s will calibrate on a cold startup and some won't. Mine is one of the ones that won't calibrate. In true Flexradio fashion there is no BIT indication to the user that calibration has failed and instead it relies on the user noticing that the radio transmits carriers all over the band (very embrassing!). If you know to power cycle the radio a second time this problem goes away and it behaves itself. So in short Flexradio failed to deliver on all fronts in IMHO: Design (FPGA timing issue. Absolutely no built in test facilities for the user) Manufacturing (missing screws). QA (failed to detect FPGA timing issues and missing screws). Support (Slow to respond. Didn't answer direct questions. Didn't fully read my answers. Not a patch on Elecraft). After having sorted all the above myself, I got down to using the radio (after re-starting the radio every time I want to use it of course). It does the basics very well and the audio from it is excellent. The radio plays very well for the casual operator, but I would run a mile before having to use one of these in a contest. Anyone who claims these are great in contests must be a casual contester who does't understand the need for 100% operability of the station. All sorts of funnies happen when you start up your 3rd party logging software (Wintest, the most widely accepted contesting software available? Forget it!). You can tell this isn't meant for serious contesting when only Writelog and N1MM have bothered to support it. Ok I'm maybe being a bit harsh here, but if I see one funny during a contest that is one funny too much. I use a K3 and Wintest for contesting and am used to that level of simplicity/performance, this is the benchmark I use against the SDR experience and it isn't pretty reading...sorry. Anyway thats it for now. I may be at the start of a beautiful friendship here, but it currently seems pretty far off in terms of contesting.