[evlatests] Terminology

[Ken Sowinski]

On Tue, 6 Feb 2007, Rick Perley wrote:

>    The letters A, B, C, and D are all well understood to refer to the
> four T304 downconverters, such that 'A' is RCP of IF#1, 'B' is RCP of
> IF#2, etc.  I think these should be retained in the descriptors.
>    Looking at the existing block diagram, we see that the three outputs
> from any one downcoverter are already labelled:  A, A1, and A2, for
> example.  (A is the 8-bit output, A1 and A2 are the first and second
> 3-bit outputs).
>    So I suggest retaining this system, despite it being 'wordier'.

Or, if you don't like numbers: AH and AL, etc, for high and low.
There is no convention (yet) for which output gets the lower
2 GHz and which gets the upper 2 GHZ of the 4 GHz presented to the
downconverter.  But on the block diagram path 1 is drawn above path 2
suggesting high and low with a different, perhaps confusing, meaning.

More confusing, is AA and AB, etc, which makes for strange looking 
combinations if you begin to enumerate all the polarization products.

We can also argue about how A through H are assigned to the
downconverter outputs.
DC1  A or A
      E    B
DC2  B    C
      F    D
DC3  C    E
      G    F
DC4  D    G
      H    H



Ken