IARU Region 1 VHF Managers Handbook - UBA

The difference between latitude/longitude on ED-50 versus WGS-84 is of the order of 300 meters.
This has no practical consequence to radio amateurs calculating their Maidenhead Locator
square other than the radio amateurs close to the square borders. Then it has consequence for
contest square multipliers.
5.12.4 EXTENDED LOCATOR SYSTEM
The proposed extension follows the pattern of the Locator system by dividing each sub-square
into a 10 by 10 grid of even smaller squares, each 0.5 ' from west to east and 0.25 ' from south to
north. These sub-sub-squares are called "micro-squares".
Two digits are added to the Locator. The first gives the longitude co-ordinate of the "micro-square"
and the second the latitude co-ordinate. For example, the region covered by Locator "IO86HA"
would be divided as follows:
IO86HA
09
08
99
56° 02.5“ N
0,25` 07
06 66 76
05
04
03
02
01
75
00 10 20 30
�
40
0,5`
50
�
60 70 80 90
56° 00,0” N
` 3° 25,0” W
3° 20,0” W
Adopted at the IARU Region 1 Conference in De Haan (September 1993) on the proposal of the
RSGB. This extension is intended only for use by stations who require greater precision than
obtainable with the Locator system. For normal VHF/UHF/Microwave work the existing sixcharacter
Locator is adequate. This extension should be published within Region 1 and
communicated to Regions 2 and 3 with a view to eventual world-wide agreement.
IARU Region 1 page 88/148 Version 5.40
VHF managers handbook
Extended
Locator
IO86HA76