E435

This is a spray shielded variant without top cap!
In the case of the E 435 the 5 pin tube without cap is the “normal” one and the other E 435 are produced to give people owning an older set with 4 pin sockets the use of more modern types of valves by connecting a cap or side contact(s). See also the other versions ov the E 435. 

Especially Philips made a lot of different versions of the same valve. Sometimes they are marked with an asterix when they have a side contact. In the case of E 435 the “normal” version looks more “old-fashioned” from the viewpoint of design and maybe are designed for a better HF performance. Later the same performance could be achieved without a cap. There maybe multiple reasons for variants.

E435: RVF-Röhrenbuch-M1,1947 Anonimo 15 Collezionista	Just Qvigstad

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