The Sylvania 12CR6 is a diode and remote cut-off pentode (vari-μ). The data-sheet shows that initial design was for use as a first audio amplifier in which AGV voltage is applied to the control grid for improved AGC operation in receivers. However, sources also show the 12CR6 used for IF/RF amplification controlled by the AGV voltage.
The 6CR6 differs only in having a 6.3 Volt heater.
The Sylvania logo.
The Sylvania name and Made in USA. The main image shows that the control grid is wound on copper supports.
The thin glass tube envelope is 18 mm in diameter and, excluding the B7G base pins, is 47 mm tall.
