From piilonen@vt.edu Tue Oct 25 17:39:05 2011
Date: Tue, 25 Oct 2011 23:38:55 -0400
From: Leo Piilonen <piilonen@vt.edu>
To: Gary S. Varner <varner@phys.hawaii.edu>
Subject: Re: number of channels for innermost 2 layers b-KLM (w/eKLM readout)

Dear Gary:

For the barrel scintillators, there will be 7 15-channel preamp boards per module.  16 modules per layer (= 8 sectors times 2 ends), 2 layers.  Total of 3360 channels or 224 preamp boards.  These preamp boards go inside the BKLM module at its high-|Z| end and mate to bulkheads mounted on the module's aluminum frame.

Layer 0 module:  54 z strips (4 preamp boards, with 6 spare channels) and 38 phi strips (3 preamp boards, with 7 spare channels).
Layer 1 module:  54 z strips (4 preamp boards, with 6 spare channels) and 42 phi strips (3 preamp boards, with 3 spare channels).

This doesn't account for one short module per layer (2 out of the 32 modules total) that goes in backward sector 2 (solenoid chimney), for which the z channel count is smaller.

Regards,
  Leo

On Oct 25, 2011, at 11:29 PM, Gary S. Varner wrote:

> 
> Hello Leo,
> 
> In preparation for the Director's review, we are starting to refine the number of readout channels actually needed.  I had been afraid that some of the components of the electronics have been left out of the WBS.
> 
> Could you please confirm the number of channels that need to be read out from the first 2 layers of barrel, presuming that they will be replaced with scintillator?
> 
> In particular, keeping in mind that we have atomic groups of 15 amplifier channels, there could be some inefficiencies, which I'd like to capture in the number of boards/modules we need to provide.
> 
> Thanks,
> 	Gary