> Looking at the HP data sheet for these - these
> are 6 GHz Low Noise Silicon Bipolar Transistors
> and *not* gain blocks as I was guessing!
>
> I still think it's a gain-grading perhaps
> screened for the app you've got  ...

Hmm... Could they be graded for noise, rather than gain?  The white one is
the first stage, and the black is the second.

--Brendan

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