Hi!
This months tube is an old European output pentode. Meet the EL3N.
This tube was introduced by Philips in 1938 and meant to be used as Class A or Class AB output tube.
The EL3N is indirectly heated and has a side contact base with 8 contacts of which 2 remain unused. The pinout is shown on the left. The heater operates at 6.3V and needs 0.9A of current. A tube which is rarely seen in use nowadays. The
Philips data sheet does not give a lot of information besides Class A and Class AB operating characteristics with a measly 8W stated as output power from the latter. I never used this tube myself and the few samples I can show were leant to me. Since the data sheet does not give any plate curves, I took the triode curves with a tracer:
Here are two samples from Philips, branded 'Miniwatt':
The EL3N had the characteristic red band above the base and smoked glass from the 'red series'.
The side contact base:
The only other sample I can show was made by Tungsram:
The box:
A few close up shots:
Since there is no getter applied at the top dome this tube gives a better view to the internals and the grids are nicely visible:
Not too much glow visible from the heater:
That's all for the EL3N. Stay tuned for more tube presentations in upcoming posts.
Best regards
Thomas
