With not that many 30's commercial transmitters surviving its more a matter of actually getting parts to make them work again, home brew was king then.
There arent any worthwhile mods for a HT-9 which is about the only prewar rig Ive seen in some quantity along with the various flea power, plug in coil, Signal Shifters. The WW2 ART-13 is always being modded.
With pre WW2 receivers in general going thru the "golden years" of radio, sets were obsolete the year of production and hams were always trying to upgrade them. Magazines were full of modification articles and the manufacturers had engineers regularly writing feature articles. At National they even did it for you if you wanted so finding a 1935 HRO or other glass tube model with HRO-5/5A1 features is not that uncommon. Other models with eye tubes had new panels with S meters done at the factory or sold as kits. Im sure some "restorer" has stained his panties and returned it to as built meanwhile whining about hammy mods.
While I wouldnt touch the AGS-X, FB-XA or the Run 1 HRO, Run 1 SX-9, SX-23 and a few others I had no problem making no holes reversible changes to the NC-101X, NC-200, SX-17, SX-28, HQ-120X as these are in regular use and cycled thru the operating positions. Certain postwar sets are also modified. I also operate CW and SSB
and I dont limit my life to the depths of 75 for AM; several on here have worked or heard me as high as 10M for the HF bands when Ive been using 30's and 40's receivers with souped up front ends.
Carl
