Welcome to Handiham World.
Amateur Radio operators of a "certain age" (like me) grew up in the days of vacuum tube equipment. Transistors didn't come into widespread consumer use until the second half of the 20th Century, and tube-type ham radio transmitters, receivers, and transceivers ruled the roost for quite some time, even into the early 1970's when transistors began to creep into low-power signal circuits and audio stages. Hybrid rigs showed up with tube finals, and then finally high power solid state became reliable and cheap and transistors and integrated circuits became the norm. Today old radio gear still has a certain cache and thus a following. Some collectors like to gather on bands like 75 meters and operate AM phone with the vintage gear. I enjoy listening to 3.730 MHz AM in the early morning hours as the old gear gets a workout on the air.
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