Jump to content


Photo

GPS displayed very strange local time.Help please!

  • Please log in to reply
6 replies to this topic

#1 FXDX

FXDX

    Sputnik

  • -----
  • Posts: 45
  • Joined: 29 Mar 2013
  • Loc: Good old Europe

Posted 02 April 2013 - 02:39 AM

hi there,

went out with my cpc925 yesterday night and had in mind an auto two star alignment. GPS linked successfully but the hand controller displayed a very strange local time. it showed 20:28:xx but true local time was 20:53:xx or so (xx for running seconds). so the difference was around a quarter of an hour.
what went wrong? isn´t it true that when using the GPS feature i don´t have to care for anythinmg else and there is no need to fix the correct local time by hand in the controller additionally?
BTW: we have changed to eueopean summertime this weekend but i had already considered that, had changed local time in the hand controller too and a remarkable difference should have been a complete hour in case of incorrect input then but not some 15 minutes.
after this failure i put the cpc away. i am not sure whether the voltage of my power supply had went too low. will charge it and try again hoping for successfull alignment then.

can you give advice please?

thank you!

Holger

ps: as i remember i had chosen a wrong star as 1st alignment star. it should have been polaris but i took a star that stood in polaris` neighbourhood but WAS NOT polaris. i slew to beteigeuse as 2nd alignment star then and finished alignment. can the first wrong star be the reason for wrong GPS time display after alignment?

#2 redfox

redfox

    Lift Off

  • -----
  • Posts: 16
  • Joined: 26 Aug 2010

Posted 02 April 2013 - 07:48 AM

Hi my cpc800 did exactly the same and went to the wrong part of the sky when I selected Saturn,gps kept comeing up with the wrong time and date,ended up turning gps off and then aligned ok,will try tonight if gps has decided what day,time it is.mine went wrong about midnight.

#3 rmollise

rmollise

    Hubble

  • *****
  • Posts: 15832
  • Joined: 06 Jul 2007

Posted 02 April 2013 - 09:54 AM

It's called "getting a bad fix." It happens occasionally with all GPS receivers.

Remember, though, the GPS doesn't know PEA TURKEY about local time, only UTC. Make sure the time-zone/DST status are correct in the HC (that would not cause the local time to be off by only minutes, however). This can also be caused if the GPS did not actually take a fix. The time you will see on your display will be what is in the battery backed clock. It is not overly accurate if you have not used the telescope in a while.

#4 FXDX

FXDX

    Sputnik

  • -----
  • Posts: 45
  • Joined: 29 Mar 2013
  • Loc: Good old Europe

Posted 02 April 2013 - 10:52 AM

thanx uncle rod and redfox!

time-zone input was correct (+1 GMT), "summertime" was set.
i will hopefully try again soon.

:)

#5 rookie

rookie

    Good Night Nurse

  • *****
  • Posts: 3070
  • Joined: 14 Jan 2006
  • Loc: St. Petersburg, FL

Posted 02 April 2013 - 06:25 PM

You can try this:
When you set up, leave it power on for a while with the hand controller connected. Go do whatever else you need to do to be organized for viewing. It will give the scope a chance to set up the GPS and time corretly, particularly if you have changed your location. Sometimes mine does not read correctly either for the first few minutes then it self-corrects. If you do an alignment before the clock corrects, it will not work properly.

If it does not self correct in a couple of minutes, then turn it off for at least 10-20 seconds then turn it on again.

#6 FXDX

FXDX

    Sputnik

  • -----
  • Posts: 45
  • Joined: 29 Mar 2013
  • Loc: Good old Europe

Posted 03 April 2013 - 01:24 AM

:waytogo:

#7 rookie

rookie

    Good Night Nurse

  • *****
  • Posts: 3070
  • Joined: 14 Jan 2006
  • Loc: St. Petersburg, FL

Posted 04 April 2013 - 06:21 AM

For clarification, when you select the "OK" during setup, the scope moves forward at that point using the time indicated and will not make any clock corrections. The time has to be correct before any alignment is performed for the scope to work properly.






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics