TRANSISTOR, BRIMAR: AC113 Germanium Transistors

Brimar transistors were made by Thorn and were also commonly branded as Mazda.  A full write-up can be found here

The AC113 is an audio frequency amplifier or driver type germanium transistor.

AC113  GERMANIUM TRANSISTOR DATASHEET

TRANSISTOR EQUIVALENTS

Being a fairly generic audio amplifier, they're listed as being similar to a number of common amplifier transistors, such as the AC125.

WHAT ARE THEY REALLY LIKE?

Testing results from a lot of 10:  The range of gain and leakage is huge - from 45hfe with very little leakage, right up to 330hfe with a lot of leakage.  Several were a bit over a 100hfe with moderate leakage.  One was dead, only useful as a diode.

So if you see some going cheap and are tempted to grab a few, buy more than you think you will need, as there will most likely be wastage.