A plastic 4-pin base with tipped S-shaped envelope. Donor's card reads: "Full wave rectifier made by the Eveready Raytheon Company about 1929. A gaseous type rectifier without filament or heater, an ...
Raytheon is best known as a major defense contractor, but the company’s roots go far deeper, starting as a major manufacturer of vacuum tubes in the early days of radio. Today, the company is mostly ...
Helium-filled full-wave rectifier. A 4-pin base with brass shell and ceramic insulator. Tipped S-shaped envelope. Serial number "5144". Two ceramic-covered cylinders are set side by side on top the ...