The 6HS6 is a sharp cut-off pentode with a controlled warm-up time of 11 seconds. The design purpose is as an IF amplifier and limiter in FM receivers.
The Sylvania name and Made in USA..
The thin glass tube envelope is 18 mm in diameter, and excluding the B7G base pins is 47 mm tall.
References: Datasheet. Type 6HS6 was first introduced in 1962.
Absolute Maximum Operating Conditions¶
Updated January 10, 2016.