On Mon, 18 Aug 2008 16:34:42 +1000, Franc Zabkar
put finger to keyboard and composed:

By my reckoning, you would need a DC offset of 2.7V before Q552 would
turn on, and you would need 1.2A in the emitter circuit of Q552 and
Q553 in order for Q551 to turn on.

Sorry, that should be Q508 and Q507, not Q552 and Q553.

- Franc Zabkar
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