[MrFixr55]

More ramblings:

Although I live in a suburb of NYC (Huntington area of Long Island, population nearly 200,000), somehow, I had always been interested in how rural people lived. This has translated to Farm Radios, of which i have several, of various eras.

The first radios were battery powered so there was not much of a difference as to whether you had a farm or lived in the city; Town or Country, you got the same radios (for the most part). Line powered radios (referred to as "socket power") appeared between 1925 and 1928. For the farmer, the radio was more of a tool, for weather and crop reports, than a source of entertainment other than church services and some "Saturday night" listening, due to the expense of batteries and inconvenience of charging the "A" battery (see below). The US Dep't of Commerce published pamphlets on how to build crystal and 1 tube radio sets.

Obviously, due to population density, electrical service was first brought to the cities. The first service was 110 VDC in NYC and other areas. The advent of AC (Google "Current Wars, AC vs DC), high voltage transmission, hydroelectric power, etc., power came to the suburbs. Due to the cost of copper and labor, it took many years (even into the 1950s or later) for electrical service to arrive to rural farm areas, and it took rural farm cooperatives and the Roosevelt era TVA (Tennessee Valley Authority) to get the job done.

Until then, the farmer had only a few choices to power the farm radio:
6Volts DC- Farm Radios were developed using similar techniques as the car radios that started to appear in the early 1930s (Tubes with 6V filaments and a vibrator power supply for the "B" voltage). These radios either used the same circuits or used certain similar tubes as ordinary 6V tubes but with less filament current, or by placing 2volt filament tubes in series. This was done because some farms were not mechanized, and the farmer would have to bring the battery to town to have a gas station charge it. The "Win-Charger" was a popular accessory on some farms, as it provided power to charge the battery which was also used for lighting. In the late 1930s, after the formation of the TVA and rural electrical cooperatives, some companies, such as Zenith, made radios that could be switched from 6V battery to 115VAC with the flip of a switch.

30VDC sets. Some larger farms would have a Delco (General Motors) 30vDC electrical generator, which would be used to charge a bank of lead acid batteries. This system would provide greater amounts of lighting to a house than the 6V system, therefore it made sense to design a 30V radio. These sets used "space charge" tubes that did not require high plate voltages.

A later development was the 2V lead acid battery (1/3 of a 6V Car battery) or 2.5V "Air Cell" battery and 90 or 135V "B" Battery sets. These were for the non-mechanized farm. The farmer would take the "A" (filament) battery to be charged, and purchace replacement "B" batteries which were sold in 45V blocks.

When Sylvania came out with the 1A7, 1N5, 1H5 and 1A5 tubes, in 1938, that could run on 1.5V A batteries and 90V B batteries, portable radios became available and rather popular. It seemed reasonable to build farm sets using the exact same circuits or even the same chassis that the portables used.

When power came to the rural area, the farm radio became obsolete. Some were kept going by purchasing a socket power unit from the manufacturer or from Sears. Others were discarded.

BTW, I don't know if I would remove the plate with the engraved message from the top of your radio. The fact that the radio was "personalized" is part of its story and may also add value.