The BC9 form Fotos is described as a general purpose and power dull emitter triode. The advert gives the filament as 1.9 V at 0.1 A whereas the dome of the valve gives the rating as 2.0 V at 0.16 A.
It is believed that the Tungsram P215 is equivalent.
The dome seen from the top.
The base pins are of the simple split pin variety. The anode is mounted horizontally onto the pinch.
Here the grid winding can be seen on the left. The three point filament support indicates a single strand V design.
Made in France on the envelope.
The original box.
The balloon envelope is 43 mm in diameter, and excluding the B4 base pins is 74 mm tall.
Reference: 1003. Type BC9 was first introduced in 1929. See also1929 adverts.
