WDØDXD

I am kind of tied to the house for a few months due to some medical procedures. So I can’t get out to the shop and work.

To keep myself busy, I have been going around the Ham Shack and working on some projects that have been started and abandoned for far too many years to mention. This week I worked on a pair of SWR/RF meters from Heathkit. The venerable HM-102 and HM-2102 meters.

The HM-102 just needed the cable replaced and a diode replaced. I used a 1N5711 in it. Having been sitting around for many years apart, I of course lost the case screws for both of them and had to go to the local ACE hardware and find some suitable replacements. After reassembly, the HM-102 was aligned on SWR and kind of the RF side. I need to find my RF probe and do a full alignment on the RF side yet, but it is pretty close.

The HM-2102 needed the most work. For some reason the builder did not install the D3 and C2 part of the internal alignment circuit. I installed a 12pF mica cap in C2 and a 1N5711 in D3. The next problem was the meter itself. I could not get it to zero with the front screw. I finally had to pop the front cover off and align it with the tab and then pop the cover back on. One foot was missing, so I designed the foot in openscad and printed it on my 3D printer using TPU filament. Finally I assembled it with the new fasteners from ACE and did an alignment using the internal alignment circuit that I had repaired.

These are going to be a great nostalgic addition to the shack.

Till next time.
73
WD0DXD