[time-nuts] Time tagging fpga

Robert Darby bobdarby at triad.rr.com
Fri Nov 21 22:37:19 EST 2014


I finally got the time tagging fpga I was playing with to a semi-usable 
state.  I mentioned in an earlier post that I was unable to compile or 
link the FTDI library but Magnus Karlsson very kindly rewrote a program 
of his to provide me with a utility to set up the USB asynchronous 
parallel interface characteristics on the PC.  Only bad thing is you're 
running blind so it pays to do a short run to make sure all's well 
before committing to a long capture.

I just finished a trial run using the Riley DMTD with three devices.  I 
have a rather shaky 5065A, an Austron 1250 and an FTS 1050.  The 
attached trace shows the 5065 misbehaving about half way through the 
run, the FTS displaying a periodic oscillation and the Austron just 
doing it's thing. It's nothing earth shattering but it sure is nice 
having the third clock to sort out who's being naughty or nice.  I kinda 
suspect the FTS oscillation is related to the battery charging cycle; 
back in 2013 TVB mentioned he'd had problems with the FTS battery 
charging affecting the outputs.  Anything specific to look at aside from 
replacing all the usual capacitor suspects?

Regards,
Bob Darby


-------------- next part --------------
A non-text attachment was scrubbed...
Name: Capture.PNG
Type: image/png
Size: 79371 bytes
Desc: not available
URL: <http://www.febo.com/pipermail/time-nuts/attachments/20141121/94926812/attachment-0001.png>


More information about the time-nuts mailing list