The five-tube TRF 20 Big Box may be the easiest to find of the early three-dial battery sets.  It went into production on April 30, 1924.  In that year 78,321 sets were produced.  109,027 were built in 1925, and 2,422 in 1926, for a total production of 189,770.  In October, 1924 the Big Box was priced at $100.  By December, 1925 the price had been reduced to $80.  The tube complement is: two '01A RF amps, '01A grid-leak detector, '01A first audio and '01A audio output.

McMurdo Silver built his reputation in the 1920s as a vendor of parts and kits.  The four-tube regenerative 620 Silver-Cockaday was one of his least expensive kits, priced at $59 in 1926.  Construction articles for this set appeared in the March, 1926 issue of Popular Radio, and the June, 1926 issue of Radio Review.  The tube complement is: '01A RF amp, '01A regenerative detector, '01A first audio and '01A audio output.

Although the seven-tube TRF 17 wasn't the first RCA set to run on house current (the Radiola 30 console was first in 1925) it was the first in large-scale production.  The 17 was introduced September 15, 1927, and 179,917 were made.  The 17 was new in many ways.  It abandoned the catacomb that RCA had used in earlier sets.  It was the first Radiola using the 26 and 27 AC-filament tubes.  The three-gang "bathtub" tuning condenser allowed single-dial tuning with better tracking than earlier designs.  The 17 was priced at $130.  The tube complement is: three '26 RF amps, '27 detector, '26 first audio, '71A audio output and '80 rectifier.

This is the only set I own with Major Armstrong's original FM band.  Coverage is: Standard Broadcast - 540 to 1600 kHz, Shortwave - 9.0 to 15.5 MHz, Frequency Modulation - 42.1 to 49.9 MHz.  The BC/SW IF is 455 kHz, FM IF is 4.3 MHz.  The tube complement is: XXL oscillator, XXL converter, two 7V7 IF amps, XXFM detector/first AF amp, two 41s for push-pull audio output and 6X5G rectifier.