Kenrad 6F6 JAN CKR audio output pentode
Type 6F6 is a general-purpose audio output pentode intended for domestic and car radios. It dates from the mid-1930s and was a well-established classic long before WWII. Its output is roughly similar to that of the well-known type 6V6 but it was considerably more sensitive and could be driven directly from the detector output, thus saving one stage of audio amplification. This was convenient particularly in compact car radios but the price of the extra gain was paid in a larger cathode and more heater power than the 6V6. As a result, it tended to run hot and, on in-car radios, a derating was normally recommended.
Type 6F6 is a general-purpose audio output pentode intended for domestic and car radios. It dates from the mid-1930s and was a well-established classic long before WWII. Its output is roughly similar to that of the well-known type 6V6 but it was considerably more sensitive and could be driven directly from the detector output, thus saving one stage of audio amplification. This was convenient particularly in compact car radios but the price of the extra gain was paid in a larger cathode and more heater power than the 6V6. As a result, it tended to run hot and, on in-car radios, a derating was normally recommended.
The operating values given are for single-ended use with an anode load of 7,000 Ohms. If a pair is used as an audio amplifier in push-pull class A, 10.5 Watts are possible with 3% distortion.
The thin metal tube envelope is 25 mm in diameter and, excluding the IO base pins, is 67 mm tall.
The 6F6 was first introduced in 1936.
Ken Rad stands for Kentucky Radio corporation and was a very important valve manufacturer for The US government and defence contracts during World War II. Based in Owensboro Kentucky,In 1945 the company's valve division was sold to General Electric and became GE's primary valve making facility. In 1987, GE sold the company to a group of investors who formed a company called MPD, Inc