I have finally finished building a combination SWR meter and antenna tuner that will allow me to fine tune the EFHW (end fed half wave) antenna I will be making to get my FT-817 radio on the HF bands I am licensed to transit on in Canada. I built the SWR-tuner under the awesome guidance of Dave VE3GSO who manages us noobs at the larc.ca (London Amateur Radio Club) kit building Wednesday evenings at the club station. Yes, we follow local COVID regulations about get togethers. As you can see from the first picture I am wearing a mask and physical distancing from others in the club station. Dave took this picture after I had finished building the box just before we tested it.
Yes, it worked first time. We tested it with Dave's Nano VNA to see the switches changing the inductance into the dummy load and the capacitance change as we adjusted the variable capacitor. We then connected it to my Yaseu FT-817 radio I had brought with me. We tested the SWR to a dummy load as well through one of the club antennas and I now have a more pressing need to get my EFHW antenna put up.
The first couple pictures show how I mocked up the placement of the meter, switches, variable resistor and variable capacitor on cardboard before cutting and drilling.
This next picture shows the meter, a switch and the variable resistor mounted to a piece of aluminium that I drilled and hand cut the hole for the meter.
The following picture shows the top switches and variable capacitor mounted. I missed taking a picture of the single sided printed circuit board that I mounted the switches and variable capacitor to before mounting to the top of the case. You see the PCB board in later pictures from the other side. You also see the hand wound torids that create different value inductors that can be switched into the circuit as part of the tuner.
The picture below shows the PCB board mounted to the top of the case and I have started wiring components together. The copper plate of the PCB board is being used as a ground plate to connect various components to ground and to help eliminate RF interference with the tuner.
This picture shows all of the hand wound inductors mounted to the switches.
This close up picture shows the SWR circuit that I built on a small PC board. I used a dremel tool to grind off the copper to create a PCB that I then soldered some SMD components and the coils I also hand wound. I later solder the small PCB to the large PCB to connect them together for grounding the two circuits together.
In this last picture you can see all the circuitry connected before putting the bottom on the case and doing up the screws for the last time. After the test I opened up the case and changed around the wires on the switch in the upper right beside the meter as it was working backwards to how we wanted it to.
Thanks for following my journey in making components to further my Ham Radio experience.
