[The General]

This 200CD was an ebay purchase. The seller packed it well & it arrived well protected & in good order.
HP introduced the 200CD in 1952 & produced it all the way up to 1985 - a 33 year production run with a few minor mods along the way, e.g. the original octal valves became miniature B7G/B9As & the last variant ditched the 5AR4 (GZ34) for semiconductor diodes. This one has the miniature valves & the 5AR4 rectifier so ticks the boxes for me. The date code on the three can electrolytics indicate it was built in 1960.
Well first job is to uncase it & see what we have. The chassis upper & power transformer were quite dirty, something had clearly been spilled on the top & dripped through the vents. The underside was clean & unmolested while the variable capacitor gearing was stiff with (hopefully) old grease.
So clean up & sort the mechanical bits first. Removing the shield around the capacitor & also the gear train made enough access to clean the chassis top & front panel with foam cleaner. The big tuning dial cleaned up nicely with Flash kitchen surface cleaner & gentle use of a mildly scratchy sponge (after having tried it first on the dial rear - always test first on a non visible surface!) I put penetrating oil in all the shaft oil holes which did free them up a bit overnight but I did have to pull the shafts out & wipe them off to really free everything up. Reassembled it all & now we have a nice smooth tuning action. Took a little fiddling to get the variable cap aligned with the gear train but the cap's on threaded adjusters. Good old HP.
Now to start on the electronics....
To be continued...