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Raytheon PNP Germanium Junction Transistors Ad
February 1953 Radio-Electronics

February 1953 Radio-Electronics

February 1953 Radio-Electronics Cover - RF Cafe[Table of Contents]

Wax nostalgic about and learn from the history of early electronics. See articles from Radio-Electronics, published 1930-1988. All copyrights hereby acknowledged.

Raytheon CK722 PNP Germanium Transistor (wikipedia) - RF CafeFebruary 1953 was just a little more than four years since Messrs. Brattain, Shockley, and Bardeen announced their invention of the transistor. This full-page advertisement by Raytheon ran in Radio-Electronics magazine announcing the world's first commercially available PNP germanium transistors. It was a big deal. Model numbers CK721 and CK722. CK721 handled about twice the collector current (12 mA) as the CK722, both with collector voltages maxing out at around 8 volts. The introductory price for the CK722 was $7.60, which in 2018 money is equivalent to $72.27* At that cost, it is hard to believe they got anyone to replace vacuum tubes with transistors. Fortunately, economy of scale rapidly brought prices down. Interestingly, CK722 inventor Norman Krim (the "K" in CK?) promoted a business relationship with Tandy Corporation / Radio Shack in selling transistors to hobbyists, and in the early 1960's became CEO of Radio Shack.

* Bureau of Labor Statistics Inflation Calculator

Raytheon PNP Germanium Junction Transistors Ad

Raytheon PNP Germanium Junction Transistors Ad, February 1953 Radio-Electronics - RF CafeNow Available!

Collector Voltage (volts) Collector Current (ma.) Base Current* (μa.)

* Grounded Emitter connection

For the first time in history, Germanium Junction Transistors are commercially available. Raytheon Junction Transistors, types CK721 and CK722 can now be obtained for your experimental and developmental use.

Here's another first for Raytheon! Leaders in the development and production of Electron Tubes and Germanium Products, Raytheon now leads the way in production of this important new electronic development.

For price and delivery information of Raytheon Germanium Junction Transistors, write, phone or wire your Raytheon Tube distributor.



Posted August 29, 2018

About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

1996 - 2024


Kirt Blattenberger,


RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while tying up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

Copyright  1996 - 2026

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

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