Reading Horizontal Angles (gon)

This reports present how angle-turning instruments work, both traditional and electronic instruments, and uses that foundation to explain the origin of systematic errors in both types of instruments. A methodology is then presented that allows these systematic errors to be minimized.

Observation procedures are set out for both traverse angle measurement, and for multi-point observations. Recording and reducing methods are discussed in examples, and each example is shown worked through in the associated spreadsheet.

The 73-page report is in PDF format. The associated spreadsheet shows the examples from the report, worked through in the spreadsheet, as well as providing user-defined functions in macros that allow addition and subtraction directly from values stored in the spreadsheet in D.MMSS (HP notation) format, as well as multiple conversion options, including between gon and radians. Formatting options are included in the spreadsheet. These formats and the various user-defined functions can be copied to other spreadsheets for the purchaser's personal use. The spreadsheet is in MS-Excel format.

The report and spreadsheet are downloaded as a single ZIP file. This version uses gon (centesimal units) in the text and examples, and UK English in the report.