The NTX-30 (top) featured special interlocking push button switches in the exciter stage. These switched in multiple 6L6 multiplier stages as required. The final stage was not switched but instead used plug-in coils. The circuit uses only 80 meter crystals on all bands. Because of the 80 meter crystal requirement and rack mounting combined with the plug-in coil final this NTX-30 stays on 80 meter CW.
The HRO Sr (bottom) mated with the NTX-30 in this rack is one of the first to sport a name tag. Up until the late 30s none of the National equipment included model identifiers. This one clearly states it is a "National High Frequency Receiver Type HRO".
Back to W0VLZ's National tour.