[MrFixr55]

Right now, I have 4 farm sets and a spare chassis for one of them.

One, an RCA 14BT2 has the same design as a "battery only" portable of the same era. 5 Tube superhet using the 1.4V tubes introduced by Sylvania in 1938; the 1A7 convertor, 1H5 IF, 1N5 Det / 1s AF and 3Q5 output. Runs on 1.5V 1, 90V B. Sensitive, tinny output, just like my BFG Mantola 419 with the same tubes except a 1Q5 instead of a 3Q5. Dale, this radio is very similar to your Motorola 45B12.

My Coronado 650 is a bit of an upgrade from this RCA except it is a little older. 90V B, 2V A. 1A6, 1A4, 30, 1A4 and 2 Sylvania 950s in parallel, I think about 0.5W output into a 6" PM speaker. Dunno how it sounds, as I don't have an opt tranny (open primary) or osc coil (mice got it), but I suspect slightly better than the 14BT2.

The other 2 are interesting, they are a 1937 RCA 5BT and a 1936 RCA 6BT (with a spare chassis). Circuitry is very similar for both sets except that the 6BT has one Shortwave Band in addition to the AM, and uses a pair of 49s, while the 5BT uses a 19, both class B output circuits. Other tubes are a 1A6 convertor, 1A4 IF, 1F6 Det / 1stAF, and 30 driver for the Class B output stage. Both sets have an 8" PM speaker with a rather hefty magnet. The 6BT has SW. Both sets run on 2V A and 135V B, with a C Battery for bias on the driver and output stage. Both radios have performance almost like a line power radio such as the 5T. The 6BT has an option that I do not have, a Vibrator supply for the B+ instead of the batteries. The interesting part of this is that from a 6V storage battery, they relied on the straps that connected the cells together (Remember them, they disappeared in the 1960s) as "taps". 2V for the filaments and 4V for the vibrator power supply (I guess that they wanted an even discharge of the individual cells of the battery).

Other 6V farm sets had very similar to car radios of the era with rather good selectivity and sound output. Zenith made models with Class B Outputs using 19 or 1J6 or more conventional single end pentodes. One model (I can't find it right now) was selectable between 6V DC and 115V AC. Zenith also marketed the "Wincharger" 6V battery charger.

Another interesting group are those sets that ran on 32V DC. Delco (GM) Fairbanks Morse, Silvertone (sears) and others made these. Some had vibrator supplies and well known 6V tubes. Others used no vibrator and used the "48" as an output tube either single or more likely push pull. The 48 could run with a 30V filament and plate supply. Apparently 30V was enough for the other tubes also.

Farm sets were available in plain or fancy table model cabinets and floor model consoles. Kind of interesting that my RCA 14BT2 was available as the 14BK console, the same chassis with the same puny output into a 6" speaker.

I have rarely seen console versions of farm radios on the auction sites. I suppose that either they were not popular or did not survive rural electrification. Often, radio stores that either existed before the town was electrified or opened after electrification would hold "trade in" promotions and at the end of the promotion a bonfire celebration was held where these traded in battery sets were burned in the bonfire.