Twin Diode - Medium-Mu Triode
The General Motors 6SR7 Vacuum Tube is a glass octal
type used as a combined detector, amplifier and AVC tube
in radio receivers. It is equivalent in performance to
the 6BF6. The 6SR7 requires an octal socket and may be
mounted in any position.
The Delco Electronics Corporation was the automotive
electronics design and manufacturing subsidiary of
General Motors based in Kokomo, Indiana.
The name Delco came from the Dayton Engineering
Laboratories Co., founded in Dayton, Ohio by Charles
Kettering and Edward A. Deeds in 1909.
These tubes were used extensively in Automobile / Car
radios. The Delco company made all of GM's tubes for
their radios. And of course GM stands for General Motors.
If you are wanting the perfectly restored car radio for
your classic wheels, these tubes are what you want!
Electrical Data:
Heater Voltage ................................ 6.3 V
Heater Current ................................ 0.3 A
Preferred Substitutes ......................... 6ST7
Substitutes ................................... 6SZ7