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Re: Fine Offset PCE-FWS20 position
Posted: Sat 04 Jun 2011 4:38 pm
by steve
Your station details show two different co-ordinates and the page has the comment that the co-ordinates supplied by the station operator are significantly different from those supplied in the weather reports (i.e. via Cumulus).
http://weather.gladstonefamily.net/site ... site=D6236
The operator-supplied co-ordinates are in the middle of a field near Gt Yarmouth. The ones you've configured in Cumulus are at a house in Old Felixstowe. So I think you need to update your station details at CWOP, and there is likely no problem with the Cumulus co-ordinates.
Re: Fine Offset PCE-FWS20 position
Posted: Sat 04 Jun 2011 4:46 pm
by nickjwhite
<sighs>
Okay guys..... It's me not you. I have obviously had a very blonde year here. Even bigger grovelling apologies to whomsoever I have I have managed to get scratching thier heads.
I have now gone to my CWOP site and found I can drag the marker to the correct location, have emailed the correction and it all should sort in the next few days.
Cumulus (as you would expect) is perfectly okay in every respect, and it is my understanding (grey haired old git here) that was fumbling.
Anyway.... it is good to talk to you fellow weather people.
For me... I think yhe appropriate 'smiley' is this one...
Thanks all <creeps back into his hole>
Re: Fine Offset PCE-FWS20 position
Posted: Fri 01 Feb 2013 10:00 am
by gluepack
I'm sure it doesn't make a great deal of difference from a weather recording point of view but the lack of decimal places on "seconds" is annoying from a map placement point of view.
With most sites it doesn't matter because they accept manual coordinates and seconds can be given with at least 4 decimal places (whether they use that or not is a moot point) so my weather station displays in exactly the right place.
However, when sending to CWOP, although you can manually adjust the coordinates (by repositioning the pointer) for the station location from a weather data point of view, the APRS location at findu.com uses the Cumulus coordinates so, visually, on a map (or, at least on Google Earth) my weather station ends up on my neighbor's property or, if I round to nearest whole number, the middle of the street.
It seems like a pretty minor change to me for Cumulus to accept decimal places on seconds.
Re: Fine Offset PCE-FWS20 position
Posted: Fri 01 Feb 2013 10:16 am
by steve
The APRS upload format accepts positions to the nearest hundredth of a minute, so adding fractions of a second to the co-ordinates would make little difference anyway, regardless of whether or not it's a "pretty minor change".
Re: Fine Offset PCE-FWS20 position
Posted: Fri 01 Feb 2013 10:26 am
by gluepack
I'm obviously missing something.
In station configuration you specify coordinates in degrees, minutes, seconds and those figures are used for the findu.com weather station location. Consequently, my station does not appear on Google Earth in the correct location as there is rounding to 0 decimal places.
43 14 15 N
27 24 59 E (or 27 25 00 E)
is not accurate. As I implied, I'm sure 100m away is fine for a weather recording point of view but it would be nice to show my weather station at..
43 14 15.13 N
27 24 59.67 E
Re: Fine Offset PCE-FWS20 position
Posted: Fri 01 Feb 2013 11:12 am
by steve
You're asking for a precision of 0.01 seconds, but the CWOP/APRS upload protocol only allows a precision of 0.01 minutes.
Re: Fine Offset PCE-FWS20 position
Posted: Fri 01 Feb 2013 12:48 pm
by nickjwhite
It would seem that it is all perfectly correct. I have just gone on a site where you pinpoint your precise location and get a lat and long from it both in decimal and non decimal.
I am apparently 51.971808 Lat, 1.374428 long, which converts to
51.58.19 and 1.22.28
All a bit confusing. As an ex private pilot I should really know all this. Must be just getting old as well as blonde.
It came about because (I think) the CWOP site must convert it wrong and puts me in Great Yarmouth on their map. Anyway, it's all okay for now.
But thanks so much for your input.

Re: Fine Offset PCE-FWS20 position
Posted: Mon 04 Feb 2013 7:28 am
by gluepack
In my book 1/100th of a minute is less than a second
Re: Fine Offset PCE-FWS20 position
Posted: Mon 04 Feb 2013 8:37 am
by steve
gluepack wrote:In my book 1/100th of a minute is less than a second
But not by enough to make a significant difference in most cases, and not enough that a hundredth of a second would make any difference. The greatest difference it could make is 0.01 minutes either way in the calculated CWOP position. Your latitude would be exactly the same and your longitude would be 0.01 minutes higher, for example, moving your marker on the map about 15 metres due East.
If you feel strongly that the co-ordinates sent to CWOP should be correct to the nearest 0.01 minutes rather than the nearest 0.016667 minutes (a resolution of about 18 metres rather than 30 metres that it currently works to, at your location), please do create an enhancement request.
Note that you can edit cumulus.ini with Cumulus stopped and put in your co-ordinates to whatever precision you wish. You'll have to redo it if you do any other changes using the station settings screen in Cumulus. And you'll still be limited by the CWOP resolution of 0.01 minutes.