@IU1KGS I built and still have the HR-1680 and HX-1681, they make their way on the air every SKN. They were my only rigs from age 14-18, and represent a lot of grass cutting and newspaper deliveries.
Their shortcomings are glaring when the daily driver is an FT-dx10.
But I can fix the Heathkits with the same modest set of tools I used to build them. They’re about the only reason I keep a set of plastic and wood coil slug tuning tools.
@2E0RKE The hot deal has been Lenovo SFF PCs that are out of Windows support. I have seen them at swaps for $175 with 32G of ram.
I picked up a batch of four, each with one honest real serial port, previously used for point-of-sale. They make great VM hosts.
@k3fnb 401A looks like it may have an extra turn for the 24 turn coil. I am counting on the inside for complete turns.
I also note that the photos make the L401A/B start wire connection inconclusive.