[Elecraft] Clock Accuracy

[David Ferrington, M0XDF]

so perhaps that could be added to the Utility
73 de M0XDF
-- 
A good cook is like a sorceress who dispenses happiness.
-Elsa Schiaparelli, fashion designer (1890-1973)

On 24 Jun 2010, at 20:11, Richard Dowling wrote:

> The RTC IC has a low voltage detector which sets a bit in the seconds 
> register.  Thus (from the IC data sheet):
> 
> 8.5 Voltage-low detector and clock monitor
> The PCF8563 has an on-chip voltage-low detector. When VDD drops below Vlow the
> VL bit (Voltage Low, bit 7 in the Seconds register) is set to 
> indicate that reliable
> clock/calendar information is no longer guaranteed. The VL flag can 
> only be cleared
> by software
> 
> So it's easy, just software ;-)
> 
> Richard
> KL0DR
> 
> At 10:43 AM 6/24/2010, Brian Alsop wrote:
>> David Ferrington, M0XDF wrote:
>>> Regarding the battery, is there a way to check it's voltage or 
>> projected life - without taking the cover off and measuring it?
>>> 73 de M0XDF
>> 
>> Reminds me of the same suggestion implemented in a few IBM prototype
>> PC'S for the CMOS battery.   They devised a circuit to go in and test it
>> many times per day.  Unfortunately, the act of repeatedly testing it
>> removed enough energy to greatly shorten battery life.
>> 
>> They dropped the idea.
>> 
>> 73 de Brian/K3KO
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