Authentic Supplies for the Transistor Historian

and Kit Builder.


Available Only from the TransistorMuseum


All Transistors Tested

Before Shipment.



Historical Background


Raytheon was the most successful of the early commercial transistor companies.  By 1952, Raytheon had established a thriving, high volume germanium diode business, so the fundamentals for transistor business were in place.  In addition, Raytheon was the leading supplier of subminiature hearing aid tubes, and this market was ready-made for the new transistor technology.   By mid 1954, Raytheon had manufactured over 1,000,000 germanium transistors, which was more than all other commercial companies combined.   These early germanium transistors were made with black epoxy cases; examples are the CK718 (hearing aid transistor) and the CK721/CK722 (hobbyist transistors). The epoxy case proved somewhat unreliable, so Raytheon began using a metal case for all transistors in 1955.  The first metal cased units were painted a beautiful iridescent blue color. This distinctive approach lasted until the late 1950s, and established a unique and historic milestone in the first decade of transistor history.  If you were a radio-electronics enthusiast in the 1950s, it is likely that you remember your first “Raytheon Blue”.












Germanium PNP Alloy
 Junction Transistor
Raytheon Type (Blues) 

Vintage 1950s

Use: Radios, Hearing Aids

And Hobbyist



Your TransistorMuseum™

Order Will Contain:


One Tested “Raytheon Blue”

 Germanium PNP

Alloy Junction Transistor

(Range of Case Styles Shown Above, with an Historical Range of Model Numbers)


Hobbyist Insert Depicting the Historical Importance of this Classic Transistor, Includes a Schematic of an Early Transistor Audio Circuit Using the “Ratheon Blue” Technology


A TransistorMuseum™ Classic

Semiconductor Storage

 and Display Envelope 



Learn All about the “Raytheon Blues” at:








$20 per Package (One Transistor)

Includes Shipping Within U.S.


Email me at

To Determine Payments Options

(Paypal or Check)






By Jack Ward

All Rights Reserved.


Your “Raytheon Blue” Transistor Order Will be Supplied in the Storage/Display Envelope Shown at Left, which Includes an Insert with Historical Description and a Schematic.