Vacuum Tube - 6C5, Triode, Medium-MU
New-Old-Stock (NOS) tube.
Also known by US military identifier VT-65A.
The 6C5 is a general purpose triode designed for service as an oscillator, detector, or amplifier. With the exception of capacitance, the electrical characteristics are identical to the 6C5G and 6C5GT. It is similar in characteristics to the 6C6, 6J7, and 57 with triode connection.