"GEOG" SITE DATABASE FILE AND PROGRAM STRUCTURE

Site data is stored in a simple serial file with arbitrary field lengths in the following form:-

Sitename~Location~Flags

The data may be edited using any text editor.  If using a word processor then make sure that the file is saved as a plain ASCII (or DOS) file to prevent any word processing control characters being included.  The tilde [~] is the delimiter between fields and at least one must be included to separate the sitename from the location. If the tilde cannot be found on the keyboard then it may be generated in the following manner:

Hold down the ALT key, and simultaneously type 126 on the NUMERIC KEYPAD keys. When ALT is released a ~ will suddenly appear! At present, only the P flag (for 'popular' sites) is supported by SITECALC.  Some sites also have a H flag followed by a number. This is the mast height of the site (used mainly for fixed stations and beacons) and is called up automatically by most programs that require the figure.  If no mast info is stored, the programs will request the height.

When editing SITES.DAT make sure there are no spurious carriage returns at the end of the file or blank lines in the body of it. All progs that read the database will throw a wobbler when they see an invalid location in the file such as a blank entry.

Location is stored as either full alphanumeric NGR or locator For 6 digit locators a four figure NGR is generated for this lower accuracy reference, enclosed in square brackets. 10 digit locators and NGRs are not allowed (yet).

Bearings are calculated using the true great circle equations; this may result in to and from  bearings not being exactly 180ø apart. This is correct (think carefully about it).  A spherical Earth is assumed, (radius 6371.29 km) so in most programs distance and bearing will not be calculated to the accuracy in LOCATION.

Most of the programmes make use of an additional database called AUXSITES.DAT.  This has a format identical to that of SITES.DAT and allows additional 'personal' sites to be called up without the risk of modifying the main database.

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