[Radio Wrangler]

Google "ECL86 r-type" and in the results you'll find an entry for The Valve Museum. It'll take you to their pages for that type number.

You'll see a table giving what each pin number is connected to.

This recipe will tell you what every pin of just about every valve (if you use its type number) does.

The ECL86 has two valve structures in its single glass bottle. The small one is a high gain audio triode (THREE electrodes - a cathode spewing electrons shaken off by heat, A grid to control their flow, and an anode to catch those allowed through by the grid) The large valve in the package is an audio power pentode (5 electrodes, a cathode and an anode as before, but THREE grids to control electron flow and to act as screens to kill of any capacitive coupling from the anode to the first (control) grid.

Pin 6 is the anode of the power pentode.

THat site will give you some explanation on what the valve is for and what it was derived from. You can click through to full data sheets with graphs of characteristics.

David