[time-nuts] FE-5680A performance - replacing fried chip

[Chris Albertson]

On Thu, Jan 5, 2012 at 4:44 PM, C. Turner <turner at ussc.com> wrote:

>
> On random things, on one of my units it had the section of the board
> populated with the +5V switching regulator - but it was not powered up:  A
> bit of sleuthing around with an ohmmeter and with the help of the data
> sheet for the regulator chip revealed which two jumpers needed to be
> installed and I was in business.  If someone else has the "10 MHz only"
> 5680A with the un-powered 5 volt switcher on board and wants to know which
> jumpers to install,


What's the purpose of either enabling the regulator or installing a 7805?
 Is it just so that you don't need to put 5V on the DB9 connector?


-- 

Chris Albertson
Redondo Beach, California