Power Pack PP11

The PP series are all layer cells, often 4  or 6 stack of exact type used in "Batrymax"/"Radio Batteries HT packs (typically 4 x stacks of 15 "biscuit" style cells). There never was a PP2.

Connection type: socket

Perhaps  5000mAH or more depending on  load

Equivalents:

• GEC BB31
• Vidor T6011
• Others: DT11, TR11, VT11

This facilitated Push Pull Direct complementary output with the loudspeaker connected to the centre tap. Some makers preferred to use 2 x AD28 for higher capacity centre tapped 9V (e.g. Perdio). Recommended for applications up to 50mA @ 9V

The 4.5V sections each use 1/2 of a PP9 interior and can be used in parallel or series.

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Elenco delle radio e altri apparecchi della Ever Ready Co. (GB) Ltd.; London