Zenith Transistor Radios Arrive in 1955-6

Zenith introduced its first transistor radio on November 22, 1955. The radio was called the Zenith Royal 500. Although introduced almost a year after the Regency TR-1, Zenith had several big advantages. First, they were able to evaluate the shortcomings of the TR-1 and others; and second, they had the advantage of both audio specialists and electronic design engineers who had solid state experience from their hearing aid product line. Here is Zenith Radio Corporation's press release announcing the new radio. Little did Zenith know of the amazing 10-year run this radio would have in its various models.

My collection has two of the first Zenith "hand-wired" Royal 500 radios. They are both black. One of the sets is an early production model, which features the embossed script writing on the back side. The other is a later model which has the "stamped" block" lettering on the back cover. This was an early cost cutting move by Zenith. My "Scripted Back" Royal 500 had to be marketed after November, 1956 since Consumer Reports recommended this radio in their 1956 buying guide issue. The Zenith Corporation was quick to self-promote the C.R. findings!!!


Here are my two Zenith 500 Hand-wired units.

This radio has chassis #7XT40Z1

This radio has chassis #7XT40

The early Zenith Royal 500's are easy to identify because they do not have vernier tuning. Also, the two knobs have a plastic bar that serves as a finger grip. Although, I have serviced two hand-wired Royal 500's that had vernier tuning!! See pictures of these two transitional models.

There is an interesting note about the Zenith tuning. The Consumer Reports of May, 1956, while quite complimentary, contained the following line in the review,"Small recessed tuning knob judged very inconvenient to use." Zenith Corporation, very concerned with quality, responded immediately to this criticism. From that point on, Zenith transistor radios almost always had vernier tuning or a large tuning knob such as the Royal 300.

7XT40Z1 Chassis View

Aldo Andreani has a nicely researched article on the Royal 500 that can be downloaded as a .pdf file. Please click here to receive a copy of his Royal 500 article.