[time-nuts] 60Hz mains clocking in computers

[Leigh L. Klotz, Jr WA5ZNU]

In 1984 we had a QBUS-based 68000 (dual 68K, due to the paging flaw) 
that ran 9-track tapes off the end and gained about a good fraction of 
an hour a day on its clock.  We complained to the vendor and they 
swapped CPU boards for us.  Tapes worked fine, and the clock was more 
accurate, but programs ran slower.  Hmmm.

Leigh.
>>>  At 1:44 AM +0000 12/13/09, time-nuts-request at febo.com wrote:
>>>>  Date: Sat, 12 Dec 2009 17:29:17 -0800
>>>>  From: Colby Gutierrez-Kraybill <colby at astro.berkeley.edu>
>>>>  Subject: [time-nuts] 60Hz mains clocking in computers
>>>>  To: time-nuts at febo.com
>>>>  Message-ID: <3058527A-CC99-4174-BE75-21DD92334155 at astro.berkeley.edu>
>>>>  Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes
>>>>
>>>>
>>>>  I'm trying to get to the bottom of whether or not any computing
>>>>  equipment made around the advent of UNIX systems (or any time-slicing
>>>>  system) used the mains cycles of 60Hz as phase lock for the internal
>>>>  system clock.  My guess is that perhaps they did not as the computing
>>>>  logic is DC based, but, I have memories of using an 68000 based UNIX
>>>>  system that I thought had its internal clock based off of the 60Hz
>>>>  mains...  Not sure the vendor anymore.