Letterboxing OS Grid to GPS Software

Hi
I have written a small program which some people may find useful If you subscribe to the Letterboxing Catalogue (Written by Mike Holiday) and use a GPS along with a compass!!! Basically the program extracts all the clues with valid grid refs from the Letterboxing Cats DB and converts the cords from OS Grid to WGS84 (GPS) format you can then filter by grid squares and various other things, if you have a Garmin GPS you can then send the Cords and Clues directly to it, or you can create a GPX file instead if you wish to import to your GPS via another application.
Currently it is still A WIP and I am ironing out some minor bugs.
Anyway if you want to download it feel free the URL is http://www.gpsletterboxing.talktalk.net/

Colin

An excellent program Colin, however I'm experiencing problems with an error report whilst attempting to upload the system DB file STAMPS.SBF. Please see the screen shots below.

Hi Dizzy
currently it only opens and convert stamps.sbf (this contains the list of all the current an old leterboxes) and the places.sbf (contains a list of various places around dartmoor). judging by your sceen shot you are trying to open the walks.sbf file? I am not sure what your copy of this file of this file contains ? I presume it must be info you have added yourself?

My copy has nothing it it so I have not tried to convert it however if you zip your copy up and email it to me I will have a look to see if there is any info in there worth converting.

Colin

Hi Colin, the walk.sbf was just one of the files I tried to upload but I do understand that your program works only with the stamps.sbf and the places.sbf. I can open the places.sbf without any problems, however our stamps.sbf contains nearly 5000 clues so maybe it's just the size of the database I am attempting to upload.
If the filepath is not c:LETTERBOX/STAMPS.SBF more so extracting this froma letterboxing stamps.sbf from a saved file on a memory stick should work just as well hopefully.
Thanks for the offer of taking a look at the file Colin but this is only the letterboxing database, plus don't take this the wrong way but I would prefer to not pass on nearly 5000 hand typed clues by my partner.

Hi Dizzy
First off I am impressed someone has entered 5000 clues manually now that is impressive. One of the main reasons I wrote this app is so I did not have to manually transfer clues from the DB to my GPS. Also it does not matter where the file resides.

I don't think it is the amount of records, the current stamps.sbf contains over 22000 stamps, as it also holds all the old ones as well as the current ones. Can you post a screen shot of the dialog you actually get when trying to open the stamps.sbf file as I can possibly work out at which point it is failing the opening? Trying to reading in a DB file in Biary format is a bit on the tricky side and I may have missed something somewhere and I can probably add some extra code to trap the error and ignore it. It may be an issue with trying to resable the database records in the correct order?

Colin

Hi Colin, I can't quiet see where you mean about the dialogue info, all I can really show you are the screen shots from start to finish while attaching the DB file extension. If there's anything I've missed then please let me know.
Oh, BTW I've just been corrected by my partner Crafty Jo that she has now typed out nearly 10,000 clues onto the letterboxing database!!! Now that's some going don't you think! This one is an old copy to try out your program.

Hi Dizzy
10,000 clues sounds like you are a slave driver
A quick question I notice that your file only contains 51000 datablocks so I preume you must of started with an empty file as the current stamps.sbf file contains 81000 or so blocks? which is about 22000 records. Also I notice from one of your screen shots that you have lots of SBF files in your folder are these just old backups ? if so can you try the oldest one to see what happens.

What I can do is do to get to the bottom of this is to do a mod on the import routine which will write each record read back out to a text file so I will then be able to see the exact record that generates the error

if that is ok with you

Colin

Thanks Colin, yes the other DB files are different database folders contains clues from other letterboxers which I have also tried to open without success.
If you can write an Mod to see if you can locate my problem that would be great. If it is my error then please accept my apologies, if not then if a downloadable Mod for your program could be available that would be great!

Thanks again,

Dizzy

Hi Dizzy have PMd you with an update

Colin

there's an update?
Cos this looks interesting

Colin wrote:Hi
I have written a small program which some people may find useful If you subscribe to the Letterboxing Catalogue (Written by Mike Holiday) and use a GPS along with a compass!!! Basically the program extracts all the clues with valid grid refs from the Letterboxing Cats DB and converts the cords from OS Grid to WGS84 (GPS) format you can then filter by grid squares and various other things, if you have a Garmin GPS you can then send the Cords and Clues directly to it, or you can create a GPX file instead if you wish to import to your GPS via another application.
Currently it is still A WIP and I am ironing out some minor bugs.
Anyway if you want to download it feel free the URL is http://www.gpsletterboxing.talktalk.net/

Colin

Colin,
Very good apps, but why would one want to convert OS to WGS84? My GPS, like most I guess, deals with OS. Letterboxes are findable by OS.

Will try the apps though.

Looks a very impressive piece of work Colin -
O.K. Just tried to run the program, loaded O.K. then when I went to upload STAMPS I got a message which said ' Bugger something done wrong' Rather strange message, so is this program safe, or am I doing something wrong

Just got a bit further and it started to load then up came the same message that Dizzy had 'Access violation at address ....'

Hi Gemma
in reply to your question the idea is not to have to retype the clues but to be able to export them to either a GPX file or directly to a GPS from the letterboxing system. For example if you use the letterboxing system software you have to reneter the Grid Refs decriptions either directly into your GPS or in a program such as Mapsource / Memory maps Etc to send data to your GPS. If for example you use map source you would enter the OS grid refs / Decription, map source then does a Helmert transform to convert it to WGS84 format and then sends it to your GPS. If you enter the OS grid directly into your GPS the GPS does the same conversion in memory. No GPS unit can you the OS grid directly as the GPS sats are configured to send WGS84 positioning data. Thw whole idea is to cut out the retyping of clues. I hope this explains everything.

Hi Sowerby Streaker
The Bugger something went wrong it just my sense of humour when an error occurs, (it won't damage anything) I think I have tracked down the issue? It is hopefully to do with the Number of Records in the stamps.SBF file being incorrect, it seems that if a person adds there own clues to the letterboxing system the Record counter in the file is not always incremented even though there are new records. (Its not the letterboxing sytem it is an issue with superbase) my app took this number and created an array (spreadsheet) in the memory sized according to the file header number of records, the issue is that there are more records than the array is sized for so it overwrites the end of the array causing the error.

Hopefully I have fixed this, It needs a bit of testing but once done I will update you.

Colin

Colin wrote:Hi Gemma
No GPS unit can you the OS grid directly as the GPS sats are configured to send WGS84 positioning data.
Hi Sowerby Streaker
Hopefully I have fixed this, It needs a bit of testing but once done I will update you.

Thanks for swift reply - thank goodness it was your sense of humour Appreciate the effort you are making as well - must be very time consuming, but a challenge

Re your answer to Gemma - I can manually put in the 10fig grid into my GPS directly e.g SX 12345 BNG 12345 so exporting straight from a file would be great. I can export from map to GPS once I have plotted my route onto Tracklogs, but not export from the letterboxing program.
Youv'e certainly got a few of us 'hooked'

Hi Sowerby Streaker its taken a fair few hours so far but am on the home stretch now once this import bug has been soterd. I am sure there are a few other minor issues (I know of one to do with redrawing the grid everytime the height is updated) but the file import is the only tricky one to fix.
I am not sure if you have tried but you should be able to open the places.sbf file and also the export.sbf (update file). Once these few issues are sorted I am debating trying to add drawing of tracks so the clues / tracks can be exported in one go. Currently If you want to add tracks you will have to export the clues as a GPX file and then import them into your mapping program and then add the tracks.

Hi Colin, I've just tried your new Mod but sadly nothing as yet will work. When I install the Letterbox.exe file I first get this message:-

Then the main program screen appears as normal.

From then on this is the process of the files:-






So sadly I cannot install the sbf files from the letterboxing files, this also now applies to the PLACES.SBF

Sorry for causing you problems.

Hi Dizzy
I will get to the bottom of this if it kills me!! Well the good news is that it read in the database before it failed so it was a problem with the array on that one, I think the second part the fixcoords had a simular problem I think I forgot to subtact 1 from the row couter which I should of done as the array is zero based. Anyway if you download and install this one

http://www.gpsletterboxing.talktalk.net ... pDebug.exe

which will overwrite the existing one and sort out the Class ID message. It should say version 1.1 in the about box.

Let me know how it goes

Colin

Errm, so sorry Colin but still no joy, this is using the STAMPS.SBF file. BTW the PLACES.SBF file works fine, here is what I get:-

Hi dizzy this is a real head scratcher as it should work!!! one last thing to try in the programs installed folder there is a file called Letterbox.ini can you open the file delete the contents and replace it with the below Basically I have made a mistake the setting below should be created when the app is first run howver they are not actually created until the app is closed the first time.

[StampList]
ShowAll=False
[Conversion]
Internal=False
[GPS]
Port=AUTO
[Proximity]
Alert=5
[Elevation]
DBType=gtopo30
[GMAP]
ShowGrid=1
[Deviation]
Latitude=0
Longditude=0
[OSRef]
fourthDigit=0
fifthDigit=0
[MRU List]
1=
2=
3=
4=

and then reopen the program.
the only way I can generate the same error is if the fourthdigit and fithdigit do not have numbers in. Once done try and run the program again and open the stamps.sbf file.


Thanks

Colin
Also if it still does not work

Crikey Colin, what have you let yourself in for

Just a few minor teething issues, theres always a few snags when developing software ( well there is when I do it anyway)

Colin wrote:Hi Gemma
in reply to your question the idea is not to have to retype the clues but to be able to export them to either a GPX file or directly to a GPS from the letterboxing system. For example if you use the letterboxing system software you have to reneter the Grid Refs decriptions either directly into your GPS or in a program such as Mapsource / Memory maps Etc to send data to your GPS. If for example you use map source you would enter the OS grid refs / Decription, map source then does a Helmert transform to convert it to WGS84 format and then sends it to your GPS. If you enter the OS grid directly into your GPS the GPS does the same conversion in memory. No GPS unit can you the OS grid directly as the GPS sats are configured to send WGS84 positioning data. Thw whole idea is to cut out the retyping of clues. I hope this explains everything.

Colin

Thanks for the info.
Keep up the good work.

Hi Colin, well I hate to say this but still no good as yet. The original info in the Letterbox.ini file is:-
[Proximity]
Alert=14

[Elevation]
DBType=srtm3

[Gmap]
ShowGrid=1

[Deviation]
Latitude=0.000000
Longditude=0.000000

[MRU List]
1=C:\Letter Box Parser\Bin\Stamps.ldb
2=C:\Letter Box\STAMPS.SBF
3=
4=

[StampList]
Showall=0

[GPS]
Port=AUTO

[OSRef]
FourthDigit=0
Fifthdigit=0

[Conversion]
Inernal=0

I have now changed it to what you have suggested within the file using one of my GUI (TextPad). Sadly I only know XHTML & CSS with a little javascript thrown in but not Java or C+.

Once again the PLACES.SBF file works find but not the STAMPS.SBF and produces the same violation pop up.

Sorry mate,

Paul

Thank you Colin, your program is working great now, thanks for all your time and effort!

Can you tell me how you can select individual boxes to download onto your GPS? I certainly don't want to try and download all 10,000 onto my Garmin.

Hi Dizzy

Yippee, finally got to the bottom of it, there are always these sorts of issues when developing software. Basically what I have done is to check the easting 2 fig 3rd fig and 4th Fig refs when reading them and pad them with '?'


So if you have say a 3 fig grid ref 754 and then a blank in the 4th digit it replaces it adds ? As a 4th digit so you end up with 754? I have had to do it this was so it will also read in the Stamps.SBF that Mike Holiday distributes.

The next step in the conversion is to replace the 4th digit with the 4/8th digit set in the options, to convert to a valid WGS lat / lon ref you need a 10 fig ref (not including the letters) so the 5th / 10th digits also have to be padded if they do not exist. With a 8 fig grid ref you will only get an accuracy of within 10 meters, if the 4/5 9/10 digits are set to 0 this will put you in the bottom left hand corner of the 10 meter square, I would suggest changing the options to 5 for the last 2 digits as this will then put you in the centre of the 10 Meter square.

Also if you have 10 fig refs what you can do is enter the 8 digit ref as you would normally and then put the 10 digit ref as the first 2 sets of digits in the description field as easting space northing no letters the description field would look like 12345 54321 rest of description if a 8 fig ref exists the app then checks the description field for a 10 fig ref if this exists it will replace the 8 fig grid with it for better accuracy in the conversion. In theory a 10 fig ref will give you an accuracy of 1meter!! This does not take into account the 5 meter accuracy of the average GPS so realistically it would be about 6Meter accuracy, which from my testing is about right.


Basically the column called selected controls which letterboxes are exported to GPX or downloaded to your GPS, This column is used everywhere in the app apart from the density grid report. So selecting some boxes in this column and then going to the map view will only view the boxes selected on the map, same goes for the printing option, it will only print boxes selected in this column.

Another tip is not to select masses of boxes to view in the map view unless you have a super duppa PC, with load and loads of memory. It will render them all but will slow your Pc down as the map is an embedded version of IE. The thing to do is just to try it and see how many you can get away with. I have loaded around 1500 just to test it and it will load them fine.

Another tip is once you have loaded the stamps.sbf file save it in the app as the lbf (letter box format) not very creative I know. But when you what to look at it again the load time will be a second or rather than 30 seconds to load the stamps.sbf file.

If you can have a play around with it and if you find any issues let me know. I am not if you have a Garmin GPS if so it’s probably worth trying to either send a few letterboxes or read a few from the device. There are some setting for comm. Ports in the options.

Also what I will do is to create a different flag colour for 4 fig refs, at the moment there I think is Red for 10 digit refs and blue for 3-4 fig refs, I find the colours handy when I look at it on my GPS as I can tell straight away if it is a 6/8 or 10 fig ref.

I will recompile a new version of the app removing the message boxes when loading the SBF File

Colin

HI Dizzy
I have now rebuilt the app you can download it from here - http://www.gpsletterboxing.talktalk.net/Download.htm A couple of other things probably worth mentioning is if you click on the column heading you have an option to filter the columns so clicking the grid east / Grid north columns will allow you to filter by grid ref


then by clicking the select button


will allow to export / send to GPS or view in the map tab.



I have also now changed the flag colours these are now

Red Flag 10 digit Ref 1M Accuracy
Blue Flag 8 digit Ref 10M Accuray
Green Flag 6 Digit Ref 100M Accuray
Yellow Flag No Valid Grid Reg

The Red , Blue, Green are push pins when viewed in the map viewer, Obviously no Yellow as there would be little or no grid ref for this colour

There are a couple of minor issues / things to note I am still working on
these -
File import
when a file is imported I currently have to strip out the following symbols " ' & ø ° ½ I have replaced the & with 'and' and the degree ones with 'Deg' however the ' and " are a bit harder to sort out sop for now I have had to remove them so 4' 6" will come out as 4 6 its to do with the GPX file format and the HTML used in the map view not being overly compatable with these symbols, it can be fixed but I have not had time.

Data entry
There is a minor issue that when selecting clues manually using the selected col with the last clue in the column you need to select the save (green tick) or it will not save the clue as selected.

Promping to Save
When either switching beteen differnet datasets or closing the app, if any changes have been made to the open database it should prompt you to save, but doesn't.

I have a Garmin Venture HC which is colour so when I send the data to my GPS the red / Blue flags appear on screen as they should. I am not sure how this will work on a monochrome GPS, weather the flags appear as just black flags or even if a monchrome GPS supports fags at all, if not I suspect they will appear as either dots or the standard garmin waypoint symbol? I cannot test this. What I can probably do if this is an issue is to change the symbols so for a 10 fig ref I can put one symbol an 8 fig ref another one and a 6 fig ref another one again. Other things to note is the amount of waypoints a GPS will hold, mine holds 500, some hold more some less. Also depending on what type of GPS you have depends on weather the name / description is trucated or not. I tend to also print the clues out as well as send them to my GPS.

Anyway I am sure there are other undocumented features (as Micorsoft would say) that need fixing / adding / changing. If you find any let me know

Hope it still works!!!

Colin

It's looking better every time Colin, just downloading your software again so I will let you know what happens with my basic Garmin (Yellow) Etrex with it;s monochrome screen!

Oops, I seem to have a problem. Downloaded the program O.K. then clicked on 'Open a letterbox DB file' and it loaded lots of clues from Mike's program, but not all i.e. I have loads of Wish You Were Here's listed (WOM) but the list is now only showing 4. Plus am I right in saying the default date for boxes found is 11/1/2001 As all the clues didn't load up, I then clicked on 'Update with Extract SBF' - this started to run then up came the Access violation message. I was able to click on O.K. and it returned me to the program. Is there a reason why its not loading all the boxes please Oh and where might I see these coloured flags???? I don't seem to have any showing Would love to get this program going...

Aha - just found the flags under 'rounded' Great

HI Dizzy
I am quite intrigued to see what happs with a monochrome GPS, also I beleive that GPS has a serial interface? I haven't tested it on a serial interface as I do not own one! The auto dectect option should scan the serial ports as well as the usb ports to find it? let me know how it goes.

hi sowerby streaker
the program by default load boxes with a min of 6 + fig grid ref ie 743 533 as you would need a min of 6 fig to get any sort of grid ref. if you wish to viewboxes without valid grid refs goto the tools / options and select list all clues and then reimport.


Can you try another extract.sbf file just to check it as could be just the file? Also try to create a new empty file in the app and then run the update from extract. it still does not work send me the extract file and i will try it. I had an extract DB with the incorrect amount of records / blocks marked in the file header which I had a simular issue with. I did put some extra code in to counter this but may need to refine it a bit. If the number of blocks in the header is less than than actually in the file it will thow an exception as I use this figure to create a dynamic array to load the data into sized according to this figure. So the end or the array will be overwritten if this is the case.
Also if you run the update in the Letterbox system first before importing the data there is no need to rerun it.

Regarding the flags scroll to the right in the grid


Mike Holidays program datestamps the box when you mark it as founds twith the current date, if not marked as found there is no default date, if you scroll to the right on the grid there is a column called date this should have a conversion of this date in it. Supderbase seems to use a very odd date format (IMHO) basically it stores that amount of days passed since 10 Jan 0001. I suspect if you have your PC date / time setting set to another country when marking as found it may not store correcly. The default for windows is American.

Let me know how you get on

Colin

Hi Sowerby streaker
I have rewritten the file import routine which should now fix your extract import issue you will have to redownload the program here http://www.gpsletterboxing.talktalk.net/Download.htm

As mentioned previously unless you select the option to import all clues you will only see ones with vailid grid refs, I have also changed it so the same now goes for the extract update files. you will still only be able to send ones with valid Grid refs to your GPS.


Colin

Hi all

I have now added some extra Functions to this the main ones are -

Added Import from Excel *.XLS for more info see http://www.gpsletterboxing.talktalk.net ... Import.htm

Added Export to Excel *.XLS Added Filtering by Density Grid
Added Report Sort order choices
Added Copy to Clipboard of Density Grid

Also the following things have benn changed / fixed
Fixed Extract update routine.
Fix Plenty of spolling mistakes
Grid filtering and sort order problems.
And load of other things

the latest version can be downloaded here http://www.gpsletterboxing.talktalk.net/Download.htm

I have tested it on my data and seems to work fine however if you have any probs let me know.

Colin

Re-loaded your new download and at last it has loaded the complete database of clues. So thought I would try the 'export to Excel'. Exported O.K. but when I came to open the file up in Excel had the following message
Microsoft Office Excel File Repair Log

Errors were detected in file 'E:\LetterBox DB to GPS Helper\Stamps Oct.xls'
The following is a list of repairs:

Damage to the file was so extensive that repairs were not possible. Excel attempted to recover your formulas and values, but some data may have been lost or corrupted.

Not really that bothered if the export doesn't work, but thought it would be nice to be able to see all the clues at once. What have I done now PS love the cartoon character in 'About'

Hi Sowerby Steaker


There is an option in the tools / options for List all clues on the last release I set it to only show 6 fig+ plus clues by default but on this release I changed the default to show all clues, but for those who only want to import just clues with valid grid refs then just goto the tools menu / options on the conversion tab just set it to 'Clues 6+ Fig Grid Ref'
This option only makes a difference when importing the data once the data is imported then this option does nothing.




If set to import all clues once the data has been imported then if you wish to only view clues with valid GPS refs you have to filter the data by clicking on the column heading 'Blue=Modified' and from the drop down list select the top 3 check boxes these represent the red, blue and green flags (I have not got around to showing the flags in the listbox yet) the 4th box is the yellow flag which is for clues without valid grid refs.



This method can be used on any of the column headings for data filtering. To turn the filters off click the red X at the bottom left of the grid.




The excel error is interesting, What version of excel do you have? I am using Excel 2000 and Excel 2007 and it seems to be fine on both (Different PC's)! Also I noticed that you saved the file to your e:\ drive is this a Hard drive or a memory stick? Can you also tell me what the size of the excel file generated is, mine ends up at about 2.9MB which has about 7600 clues in.

When I wrote this bit I took the easy option on the export to excel which only toook about 10 minutes to do, I can rewrite this part if other people have the same problem, it will only take about an hour to do at most.

If you have a spare 5 minutes some time if you could try it again just to see if it still does not work. Could you also try saving the excel export to your c:\ drive

My Fav bit of the entire app is actually the density grid, I like the abilty to filter the stamp list by selecting an area in the density grid right mouse click and select filter DB, not the trickeist bit the most fun to write. (Yes I know i'm sad)

The pic is the one I use on my letterbox stamp, he looks a bit confused which is me everyday at work


if you find any other problems please let me know.

Thanks

Colin[/img]

Morning Colin - I've had another play and managed to export the database to Excel and save it on my C drive (I have my letterboxing programs on a stick so that when I'm bored and in work, I can use it ). I am on Excel 2003 and the file size is 2.87mb, so that seems about right. It has worked O.K. now thanks. So now am going to play with the filters and see if I can just get the records out for the 'not found' boxes. Looking good - well done

Hi Sowerby Steaker

I have seen the file corruption problem before with memory sticks , Its quite common. I think it is due to the speed of the memory stick not being able to keep up with the file writing. The obvious work around is to write the files to the c:\ drive and then copy them back to the memory stick. (as you did)


A couple of things to note when plugging you memory stick into another PC and running the app you make get a class not registered error and / or cannot find Grid in Quest DLL error. The class not registered error can be ignored. when the app installs it creates some entires in the registry. which would not exist on the other PC unless you reinstalled the app on it.


However this should fix the error -

You can reinstall the app on the other PC with the same install path or
Goto the start button and Select the Run command (XP) or on Vista in the 'start search' box type

regsvr32 "E:\LetterBox DB to GPS Helper\giq60.dll"

Where E: is the drive letter asigned to your memory stick on the PC

I quick option would be to create a batch file and copy the line in there!

I am glad it is working, if you have any ideas for improvements / changes please let me know.

Colin

Thanks Colin - just got back and so will have a chance to 'play ' with the program tonight. Sorry I missed you at the meet, I hear you met Dizzy who is also trying out your program. Wonder if anyone else out there is having a go with it?????

HI Sowerby Streaker
I popped in to the meet but am not a fan of crowds so did not stay long plus I had my children with me and they wanted to go off walking so I was only there for about an hour at most.
Prehaps I will see you at the next meet

Colin

Hi Colin,

what a great program to work with Mike Holidays SBF ...

Just a few thought ... When I export the waypoints to my Garmin GPS Etrex Vista HCx the OS British Coordinates are off by 4 - 8 meters?

Do you know why this is the case and what I can do alternativly to get the correct Coordinates out to the GPS?
Same problem with GSAK and Anquet Maps program. Only with MapSource do I get the right data over exactly.

Second I noticed that the exported .gpx file can only be opened in GSAK not in MapSource nor in Anquet Maps.

Hi blue Danube family
Glad you find the program useful
The WGS settings generated by the app are correct? Well according to the OS they are, I use the same Conversion DLL as the OS do on there web site written by a company called Quest. I have tested it on Dartmoor and the accuracy is well within 5 meters. The actual accuracy of the DLL is allegedly to with 1cm if a large enough OS grid ref is supplied.

I presume you are looking at the co ordinates in Google maps and noticing they are not quite in the correct place? I pondered this issue for ages trying to figure out where the problem was and I must say it did confuse me for ages so what I did was to add 2 boxes in the options for lat / lon deviation



if you set the Lat to -0.00006 and the lon to 0.000051 (I think off the top of my head I will look up the original setting if you want me to) and then reimport the stamps.sbf (OR select all the waypoints and hit the lat lon Button) the stamps will be in the same location or close to as they are in Google maps, however after doing some on the ground testing I have come to the conclusion that Google maps is not overly accurate as it does not take into account all the fudge factors in the OS national grid hence the difference. I would leave them set at 0 if I were you and not worry about how the grid refs display in Google maps. Also one other thing to bear in mind is the accuracy of the GPS taking the ref and also yours most WAAS enabled GPS's have an accuracy of +-5M so in theory you can have a variance of 10 Meters as mentioned above in the real world this is more 5M or less.
There is a way to test the Accuracy, if you go into your back garden and mark a waypoint or 2 then in either my app or map source download the waypoints from the GPs and look at them on google maps, from my tests ther is nearly always a shift in Lat / Lon in Google maps of about 3Meters

Also have you by any chance Set the heading settings on your GPs to 004W or similar rather than leaving it on grid? If so what is happening is your GPS is taking this deviation into account and calculating the grid ref with it factored in. The GPS will do a helmet conversion on the WGS cords so you can see them as OS Grid. If you change the heading setting to grid or probably Magnetic they will display correctly on your GPs?. It’s basically an issue with the variance being different where you are than it is on Dartmoor. Try setting it to grid and let me know.

I suspect what map source does when it send GPS coordinates to your GPS is it reads in the heading deviation (if you have set this manually) and factors this in when sending the data to your unit whereas GSAK and Anquet Maps and my app do not do this, as mentioned above I set mine to grid rather than set it manually! Which then give the correct results!

Sorry about the map source issue with the GPX I have fixed it now I think? You can download the fixed version here - http://www.gpsletterboxing.talktalk.net/Download.htm


Hope this info helps

Let me know how you get on

Colin

What happened to the days of finding boxes by use of bearing and a compass?

My thoughts exactly - I have found the program useful in conjunction with Mike's program, but no amount of accuracy from GPS to map will put you on top of the box. The idea surely is that these GPS's get you to the right area and make walks easier to plot on the map. When I am out, should I struggle with long distance bearings, or can't get the bearings to line up, then I use the GPS as backup.

Colin, thanks for your quick reply.

Here a few points I have noticed (I have not tried your new version from yesterday yet):

- GPX File Saving for use in other programs: I was able to load small sized GPX files into Anquet Maps, but not large sized GPX. Mapsource: is not able to load GPX files at all. GSAK works fine

- On another note: when I import the .SBF file I see that around 90.000 records are imported however not sure what it imports. I noticed that only 1.800 clues are listed, whatabout the others? Are they all "deleted boxes" in Mikes System and not imported?

- Really like the SBF import and especially SBF Update possibilty. Does that mean I do not need to use Mikes Sofware anymore, yours is way more user friendly. Also really like the import coordinates function from the description box, wowww!!!!

- One function really would be great. It takes hours and hours for me to cut and paste WOMs into my database or also your new program. Is there a way to incorporate a function to "Grab" data i.e. from a Word file? That would save a lot of time ...

- Concerning the inaccurate OS Coordinates, I noticed it was my mistake. I had set my GPS unit to use OS British Grid Coordinates and did not think that your program was meant for usage of WGS84 coordinates on my GPS Unit. So if I understand it properly your program transfers the OS Grid to WGS84 and on my GPS I need to set my GSP to WGS84 and word with dddd.mm.ss.

- Could you perhaps add all WGS84 datums to your program for viewing, that would be great. Currently I only see dddd dddd.mm ,but not dddd.mm.ss That would be great because other program like GSAK and MapSource use the ddd.mm.ss

- One last point, are really all filters from Mikes program in your program, I had the feeling not all are there?

- One last last point. The GoogleMaps view only shows the Googlemap without the waypoint markings/flags ... is that supposed to be like that?

- One final final comment. I would be great if the OS Dartmoor OL28 Map could be built into the program, but I presume this will not be possible.

Hi
I do agree to, I never wrote the program to replace my map / compass as I find this part of letterboxing the most enjoyable, I tend to use my GPS as a backup so If I am struggling with finding a box I will get it out and home in on the area. (Sometimes to eventually find the box has gone) It also helps when the children start to lose patence as I can give it them to use (Map reading is a bit beyond my 4 year old). Personally I tend to use the program more for route planning.

As I have mentioned in the past the Accuracy is only +-5 Meters with an average GPS so you really still need to use the clues as well. I think one of the best parts of a GPS is the track logging as when I get home I download the tracks onto my PC to see far I have walked and also to look at the actual route I took compared to the one I planned, if you try hard enough you can draw some nice patterns in track logs rather than the straight lines I originally plan.


Colin

Hi Colin, you seem a very clued up guy with GPS to computer etc. How do you download your track back to the computer then. I very often would like to know exactly how far I have walked, but don't know how to get it off the GPS. I know there are sometimes some very squiggly lines on the screen, especially when I walk around in circles looking for a box. Then walk on to another, then find I have missed one so have to go back etcc. I have a Garmin GPS 12 - bit of an old fashioned brick, but serves my purposes O.K.

Hi blue Danube family

The new version should fix the Mapsource import!

What you are seeing is the amount of data blocks in the stamps SBF file, to read the SBF binary file I have to read in each data block and reassemble the file, its gets a bit complicated but basically a data block is equal to 64 bytes, each record (stamp entry) can consist of multiple blocks, most would be 2 or 3 data blocks but this varies, so hence the 80,000 blocks, there is a very uninteresting web page of the SBF file format here. http://isrc.interapps.com/file_formats/ ... ..sbf..htm which helped me to work out how to read the file. The file does contain all the deleted boxes as well, so this totals about 22000 records however I do not import the deleted ones as there is not point. The 1800 records to see listed are the ones with valid Grid Refs, there is an option in the options to import all not deleted records with avid or not Grid refs.

It will update the stamps.sbf file with the extract.sbf file however I would still do this with Mikes program and then reimport the stamps.sbf. As I am still working on some minor technical issues.

I haven't really thought about importing from word I added a function to do it from Excel. If you let me know what sort of format do you have your clues layed out in word I can have a look @ it.

On the GPs side I think we are talking at cross purposes, basically all GPS use WGS84 format as the underlining coords, if you open a GPx file in notepad it holds the lat / lon in Raw WGS84 format. What happens on your GPS is it does an internal conversion so you can see it as OS grid, but it would still actually use the WGS84 format, the conversion is just for a more friendly user view. However if you set a user defined deviation on the GPS unit e.g. 004W the GPS calculates the OS grid with this deviation added. So if the area you are in has a different deviation from the area of the grid ref the grid ref will display incorrectly. So basically you should be able to set your GPs to OS Grid but leave the deviation set to grid this will account for the deviation where you are and display the grid refs correctly. (Hope this makes sense)

I will add the ddd.mm.ss as an option when I get a few minutes.
If you let me know what filters you require I can add them for you. Alot of the filtering is currently done in my app by clicking the column headings which will show a dropdown box to filter the data by



There is a column called selected this column is used throughout the program to control what is printed / shown. If you tick a few clues and then switch to Google map view they should appear on the map. What I tend to do is to first work out which grid squares I am planning to walk and then filter those by click on the easting / northing column headings and selecting them from the list this will filter to those grid refs, then tick the clues in the select column if you then switch to Google map view they clues will appear. Another way to do the same thing is to goto the density report and select some grid squares, then right click on them and apply the filter.

It is not possible to use the OS maps due to licensing however I am currently looking into he possiblity of using the openstreetmap maps which can be downloaded for free. I am also looking into adding an inbuilt route planner but this is proving a bit more tricky than I first thought but I am sure I will figure eventually.

Hope this all makes some sort of sense and that I have covered everything in your message

Colin

HI Sowerby Streaker
I presume you have the PC interface cable for your GPS? Did it also come with a copy of Garmin mapsource? if so you can download the tracks straight into it from your GPS, if not then there is a way to get a copy for free see the top post here http://forums.gpsreview.net/viewtopic.php?t=4802

This will give you the full version of map source with the world basemap all you then need to do is go to the transfer menu and receiver from device and select tracks.

There are lots of other programs out there that will do the same but I like using mapsource.

Any probs let me know

Colin

Wow, the program is getting better all the more...

Here some points however still ...

The Googlemap Waypoints are scattered in Googlemaps all over the world. Could you send me your Email Adress via PM and I will send you the screenshot. Also not always does the Googlemap appear, often the page is blank even if I select the rows by selecting the checkbox per row.

Conc. the .gpx still does not work at all for mapsource. For Anquet Maps and GSAK works about to around 100 selected clues, then does not load anymore.

Conc. Word Import (Grab function) that would be great. I would like to send you some of the WOM Word clues for you to view. Obsiously they are not always in a proper format, just text which is grouped together. Would need your emailaddress.

Filters: All there, fine, my mistake

Why not use your program for data entry of clues i.e. WOMS ... looks stable. It would be far far more easy to enter data with your program.

Concerning the issue of gpx export

.gpx "does not pass xml validation" ... "error in xml file line ... not well formatted"
this is what i get as error messages in the different programs when I load the .gpx file ...

Hello there - I have downloaded your programme and it looks very useful -

I have been letterboxing for several years and have visited over 200 boxes the good old fashioned way (plus a few charity walks!) now I am keen to keep a record on my GPS and PC however I have a question -

I know that I can get the letterbox clues book from the meet but is there a digital version - I note you mention sbf files in this post - can these be paid for or do I have to create my own list from the book?

Hi Oxman
there is an electronic version of the cat which can be purchased from Mike Holiday (his address is somewhere on the forum) Originally I wrote the app to read in the database file (SBF) from Mike Holidays program and convert the os grid refs to WGS84 coords (GPS format). Since then I have added various other features that people have asked me to add.
The latest version is v1.4.5

Hope this Helps

Colin

Colin - your a star! thanks

I will track down Mike Holiday for a digital catalogue.

Cheers