OpenGD77

Hi,

I've recently noticed that Satellite predictions seem to be out by about 1 hour on both my MD9600 and GD77.

I have checked that the time, date and location are correctly setup in Radio Info.

Using both the ISS Detector APP and https://www.orbtrack.org as a comparison.

Any ideas on what I may be doing wrong, I have had this working before.

Firmware version on the GD77 is Feb 28 2022 and MD9600 is MD9600_firmware_V5HW20220617.

Regards Mike

I have also noticed that I get a different time difference if I change to local time, update the timezone re-enter the time and date.

VK4MWL wrote: ↑

Sat Jul 02, 2022 12:18 am

I have also noticed that I get a different time difference if I change to local time, update the timezone re-enter the time and date.

You have to set the correct offset to use local time. The firmare can't compensate for daylight saving, because this varies depending on exactly where you are in the world and the date. The calculation for daylight saving is far beyond what could realistically be put into the firmware

Also that predicted pass on your phone is completely different to the pass on the GD77.

Display is North upwards always.
So the pass on the GD77 is going North to West but the prediction on your phone is either going north to east

Thanks for the reply.

I'm located in Brisbane so no daylight saving.
Local time 12:09 2/7 - UTC 2:09 2/7 - Radio is showing correct date and time, timezone set to +10:00
Location QG62NK - Correct for where I'm located

Next ISS pass on radio 03:08:30 UTC west to south
Next ISS pass on ISS Detector App 02:45 UTC west to south

I will check my satellites.txt file.

Updating the Satellite keps file has fixed it.

Thanks for your help Roger.

VK4MWL wrote: ↑

Sat Jul 02, 2022 2:40 am

Updating the Satellite keps file has fixed it.

Thanks for your help Roger.

OK

The ISS is notorious for modifying its orbit very often, to avoid space junk.

Sometimes the prediction dataseta aka Keps from https://www.celestrak.com/NORAD/elements/amateur.txt or AMSAT don't get updated immediatly when the ISS moves orbit, so its essential to get new keps every day if you want to use the ISS