As indicated earlier, the QDX is now on the air! I have tested on both 40M and 80M and am so far quite impressed with the performance. There are a number of "quirks" I have run into, but most deal with the behavior of the firmware in the board. Below is the latest write-up --- Control Board mounted into Case --- This was easy to assembly and luckily none of the "tacked on" components collided with the case. and here is the new "Rig" mounted along with my others... There was barely any room for it :) After booting, I plugged in the USB cable and the system was recognized easily by Windows 10... A serial port for CAT control and a Sound Card interface was added as expected... The next step was to update firmware to the latest revision from the QRP website... The QDX has a neat feature, when placed into firmware update mode, it will appear as a USB drive on your PC and you merely just need to copy the firmware to this drive to update it. Pretty slick! Once the unit was updated, I rebooted and started some system checks to check the RF and Audio Performance... These checks are built into the QDX itself and accessible via the serial port. There are a number of other tests and configurations that can be performed on the unit also... The picture below is an example snapshot from a 40M RF Band Sweep. (However it did not scale down well for the photograph) . These tests exist so you can determine if you did a good job with winding of the torroids and if the bandpass is tuned optimally to the desired frequency band. All in all, bands looked good, with maybe the exception of 30M. The center of the bandpass on my unit was low and centered around 9.6Mhz. I may have made some kind of mistake wrapping this toroid and may need to go back in and "tweak" it a bit to get it centered correctly.. I will try out 30M today before doing anything, and then decide which direction I want to go. A second set of tests were included in the terminal interface to test Audio Passband performance for each Ham Band. In all cases the results returned back no attenuation of audio between 200Hz and 3200Hz for USB audio and 60db attenuation for unwanted LSB audio. No tweaks needed on these filters. It is also possible to change the QDX to LSB mode were these two reading for LSB and USB should be reversed. --- FT8 Performance -- Next step was to get on the air! I started a new configuration on WSJT-X for the QDX. You have to setup the CAT configuration of WSJT-X to emulate a Kenwood TS-440S. I also needed to configure the soundcard settings to the QDX. --- Antenna Tuning ---- Since I am using a multi-band antenna, it was not wise to simply plug the QDX in and start transmitting as some of the bands (30M) have a less than desirable SWR for the QDX's small transistors. I have an auto tuner attached to my ICOM-7300, but wanted to use it with the QDX also. I inserted a COAX switch between the ICOM-7300 TX out and the QDX TX out and routed the output of the switch into the auto tuner. I would first switch in the ICOM-7300 and initiate a tuning cycle. After the tuning cycle was complete, I then switch out the IC-7300, and switch the in QDX . This worked well for verifying the auto tuner was setup correctly before allowing the QDX to use it. The auto tuner also has a watt meter that could be scaled down for QRP use and give me a good idea of what power level the QDX was transmitting at. --- CONTACT!!! --- Reception of FT8 signals was excellent... FT8 was extremely busy last night on 40M and it was hard to find a gap on the waterfall to attempt communication. After calling CQ for a bit I made contact with N7RI in Cheyenne Wyoming and was a little suprised by the R-06 signal report I received, figured it would be much lower. I ended up making quite a few contacts on 40M and 80M in a number of states before receiving threatening comments from wife to come to bed. I also received responses to my CQ from Argentina and another from Portugal. However, in each case, was unable to get through the exchange successfully because of the frequency being so crowded and each time had someone coming in and grabbing my spot on the waterfall. This morning I was able to do a rare QSO with Hawaii on 80M and an even rarer QSO at +33 (!) with KE80, Finally, to check how well the QDX was getting out, I checked PSK Reporter... Here are the results... --- 80M map plot of stations receiving my signal last night --- --- 40M map plot of stations receiving my signal --- ALL ON 5 Watts! This has been a pretty fun project... I plan to test the performance on 20M and 30M next, and may need to disassemble the unit and tweak the 30M bandpass torroid. But all in all, pretty happy with the time it took to build this.... Thanks for watching!