[amsat-bb] Re: GPS Time observation

Vince Fiscus, KB7ADL vlfiscus at mcn.net
Thu Feb 2 15:22:57 PST 2012

At 03:44 PM 2/2/2012 -0500, you wrote:
>The difference between GPS time and UTC is adjusted as necessary. The 
>adjustments come in the form of leap seconds and are added when needed at 
>the end of June or December. The difference between GPS time and UTC is 
>currently 15 seconds. There will be a leap second added this coming June 
>30. What is being seen is the casual user GPS receiver software does not 
>put a high priority on time display.
>John  WA4WDL
>From: "Jim Jerzycke" <kq6ea at verizon.net>
>Sent: Thursday, February 02, 2012 3:18 PM
>To: <amsat-bb at amsat.org>
>Subject: [amsat-bb] Re: GPS Time observation
>>I think this has something to do with "GPS Time" vs "Earth Time".
>>IIRC, GPS time doesn't take into account the Leap Seconds that have been 
>>added to Earth time since the first GPS satellites have been launched. I 
>>think some of the newer receivers can compensate for this, but I'm not sure.
>>It's been about 14 years since I last worked in the GPS industry, and I'm 
>>a bit rusty on all the new stuff!
>>73, Jim  KQ6EA
>>On 02/02/2012 04:57 PM, George and Cheryl Abbott wrote:
>>>I'm not sure about GPS,but I have noticed that the clock on our cable 
>>>box is off by up to 4 seconds at times.Customer service was not aware or 
>>>concerned when I let them know.

Thanks everyone for educating me on GPS.  I wasn't concerned that it didn't 
display the exact time, but I was kind of curious as to why it didn't.


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