ComputerVoltageSources

Two of the beta builders have made good progress with ordering parts 
and building boards. Neither seemed to have too much trouble 
soldering the SMT DACs. Since we've only found one error in the parts 
list, and drmabuce has posted a lengthy progress report about a nearly 
fully functional CVS, I updated and consolidated the design 
documentation.

The latest documentation is included in a single ComputerVoltageSource 
pdf file in the "Files > Hardware > CVS Module" folder. This document 
contains specifications, schematics, parts list, PCB images, a 
snapshot of the latest FAQ database, and a recommended build and test 
sequence. I would encourage everyone who is building a CVS to include 
their tips, suggestions, and learnings in the CVS FAQ database.

I also uploaded the PCB design file and a readme in zip format to the 
same folder. The readme contains information on how to order a PCB. 
They are economical in quantities of 8 or more.

The DAC still seems to be in allocation. I used the Analog Devices 
AD5726YRWZ which is showing a November availability on their page. The 
board can also use the Texas Instruments DAC7714UB or a DAC7715UB. 
The TI page shows only limited availability of these parts in Europe. 
The TI page previously indicated an August availability (they have
been in allocation since last December!). The board should be able to 
use a DAC8420 and Digikey has 12 SMT parts listed at the ridiculous 
price of $45 each. I never pursued this part since the price was so 
high so someone would need to check out compatibility.

I would suggest whoever is interested to contact Analog Devices and TI 
and find out what the latest DAC availability status is. This is 
certainly a precursor to organizing an order of boards. Again, just to 
clarify, I do not intend to sell this board so don't ask me. The 
design file is public so those that want the board will need to 
organize their own group purchase.

Dave