This is what we are starting out with. The top board is the user interface board and the lower one is the RF board. I am following the instructions on GitHub for the steps. We will start putting the connectors onto the UI board first. https://github.com/df8oe/UHSDR/wiki/Building-Your-Very-Own-mcHF #opensource #hamradio #amateur #qrp #electronics #assembly #kitradio #mchf

Following the instructions I am starting with the UI board. I am adding the audio jacks for “Line OUT", “Line IN”, “MIC" and “PHONE”. And I already run into an issue. I want to use a Baofeng hand set with this, and it uses an electret microphone. For that to work I need to solder on an 0805 680Ohm resistor at R8. It is not included in the kit and I don't have such huge resistors! I need to order it :/ (starting a DK cart I guess ;) ) #hamradio #kitradio #mchf

Next is the UI board to RF board interconnect pin header and the USB host connector. This brings us to the massive list of suggested modifications to the original build of the board. It recommends putting pin headers on the UI board and pin socket on the RF board. So I did that. https://github.com/df8oe/UHSDR/wiki/Recommended-Modifications #hamradio #kitradio #mchf

Next I have added the encoders and the tact switches. Interestingly the pads for the SMD tact switches are genuinely massive, because of that, getting them soldered on centered and straight is much harder than it should be. :/ #hamradio #kitradio #mchf

I decided to temporarily put the case and boards together. I want to make sure that the recommended standoff distance for the LEDs is what I want. #hamradio #kitradio #mchf

Ok, they turned out all right. There is way more wiggle room in the case openings than I originally expected. I did not have to be so precise about it. 😅 #hamradio #kitradio #mchf

Last but not least part of the UI board is the display. Original design has the LCD module soldered directly to the PCB. There is not much vertical space to allow for connectors. I decided to remove the pin header shrouds, cut the pins shorter and use screw machine terminals to make it removable. #hamradio #kitradio #mchf

Now that the UI board is fully assembled we can test it! It is also time to update the bootloader and firmware! All we need is some jumper wires and a USB cable. And the verdict is… NO SMOKE! #hamradio #kitradio #mchf

Now that we have the UI board assembled and tested it is turn to start on the RF board. Let's do the simple stuff first and solder on some connectors. Power jack, KEY and ACC, the BNC for the antenna, and an off the shelf balun. I have to order the temperature sensor chip that would be added in this step to for some extra TCXO temperature compensation stuff. #hamradio #kitradio #mchf

I have mounted the first few hand wound devices on the board. A balun, a choke and two transformers. They are part of the power amplifier circuit. (still getting the hang of hand winding and soldering these in…) #hamradio #kitradio #mchf

As a side-quest. To make my life a bit easier. I have taken the mcHF design files and imported them to KiCad. You can find them on my GitHub. https://github.com/esden/mchf-kicad and yes they open in KiCanvas!!! ;) UI Board: https://kicanvas.org/?github=https://github.com/esden/mcHF-kicad/tree/main/v0.6.3/ui RF Board: https://kicanvas.org/?github=https://github.com/esden/mcHF-kicad/tree/main/v0.6.3/rf #hamradio #kitradio #mchf #kicad

Now I need to wind all the inductors for the Lowpass filters. Each filter consists of 3 inductors. I started with the 80m band toroids. 24, 27 and 24 turns each. #hamradio #kitradio #mchf #kicad

Here we go! All the filter inductors are wound and soldered in! I tried my best to do an even and clean job... I did check them with the low cost LCR meter I have and they seem to be in the ballpark of the specified values. #hamradio #kitradio #mchf

Last hand built items on the RF board are the SWR/PWR meter transformers. I have to admit, getting those coax windings was a major pain in the back side… I am pretty sure the bend radius is “illegal”. I have the feeling that the board was not originally designed with those coax windings in mind. But as far as I can tell things are soldered and connected where they should and the two toroids are wound in their opposite directions as the documentation describes! 😅 #hamradio #kitradio #mchf

After mounting one stray relay on the back side of the board, we can finally assemble the parts that go onto the "front side" of the RF board. Another funky balun, 3 relays, some connectors and a neon bulb to protect from the antenna zapping us. :D ⚡️ #hamradio #kitradio #mchf

To install the TO-220 PA MOSFETs and LDOs it is necessary to partially assemble the RF board into the case. It is really hard to get the nuts onto the chassis bolts so I decided to solder them onto the tabs. (these are the moments I praise having a JBC iron!) #hamradio #kitradio #mchf

Remember how at the beginning we were missing a resistor for the electret microphone? It arrived, so let's solder it in before we assemble the whole radio into the enclosure. #hamradio #kitradio #mchf

First thing for the case is to screw in and solder the wire to the speaker. #hamradio #kitradio #mchf

Next is the RF board we spent so much time on, followed by an RF shield. The enclosure comes with an RF shield but it needs a bunch of modifications. So instead of doing that I designed my own RF shield and ordered it from Send Cut Send! It worked out great. You can find the design on my GitHub. ;) https://github.com/esden/mchf-rf-shield #hamradio #kitradio #mchf

Now the UI board can be mounted on top of that. Let's finally remove that pesky protective film from the LCD display! #hamradio #kitradio #mchf

The front panel has some silicone covers for the buttons. But oddly enough these are not mats that fit the hole pattern. One has to clip the buttons apart and then insert into the button holes. It makes the assembly a bit awkward because the buttons love to fly out of position. #hamradio #kitradio #mchf

And here we go! We have a fully assembled mcHF QRP radio! There is more work to do, but let's sit back and enjoy the view l for a little bit! :D #hamradio #kitradio #mchf

I have to wait for a dummy load and a few other bits and bobs to arrive before I can calibrate the radio and try to go on air with it. In the mean time I am trying to get familiar with the controls and while doing that I managed to receive some SSB on 40m! 🎉📻 #hamradio #kitradio #mchf