Price is for 1 NOS preamp tube. Comes straight from the military surplus storage. This is very desired vacuum triode valve made in the mid-1960s in the US. With D-getter, and welded black plates.
Tested VERY STRONG as follow:
Ia1 = 11.6 mA | S1 = 1.8 mA/V | Ri1 = 7.5 kOhm | μ1 = 15.8
Ia2 = 12.8 mA | S2 = 2.5 mA/V | Ri2 = 6.9 kOhm | μ2 = 15.2
Tested under: Uf = 12.6V | Ua = 250V | Ug1 = -8.5V
Good starts at Ia=7.0mA
Shipping will be Airmail registered with tracing number. Other shipping methods available on request.