by Wilf James.


Published by the Navigation Services Dept
                        Introduction				 1
                        Warnings and Cautions			 1
                        Choosing the location			 1
                        Preparing the site			 2
                        Building the Beacon			 2
                        Functional testing			 2
                        Final commissioning			 2
                        Maintenance				 3
                        Parts list				 3
                        Special Tools and equipment required	 3
                        Associated publications			 3


The Mark 27 Beacon is intended for use as a long range navigational aid. It provides bearing and distance information in a combined signal which which is receivable on all established navigational routes. Mark 27 beacons can be used in combination to provide positional information anywhere, but accuracy will depend on the apparent intersection angles of pairs of beacons used in combination. The Navigational Service is continually installing new beacons to enable ever more accurate fixes to be obtained over existing and planned transport routes.

The Mark 27 Beacon produces pulses of high energy which are harmful to life at short ranges. Operators are warned that they must ensure that they are adequately protected from the harmful effects of high energy radiation.

The Mark 27 Beacon uses high mass components. Operators should ensure that these components are handled by the appropriate construction equipment. Any attempt to stop the beacon from operating after it has started is likely to cause a catastrophic failure in one or more components. No attempt should be made to adjust the beacon after it has been commissioned. Any attempt to adjust the beacon could cause the liberation of the energy contained in the beacon's power source - with fatal results.


NOTE: The location of the beacon will normally be decided in advance by the Navigation Services Dept. However, the location of a beacon in a newly charted region may be chosen by the local surveying officer where signals from existing beacons are too weak to permit accurate navigation.
1. The site for a new beacon shall be at least 100 NU (navigational units) away from inhabited planets and 25 NU away from the nearest type 8 star.
2. An estimate should be made of the likely routes which will develop when the beacon has been established. The beacon shall not be located within 10 NU of any of these routes.
3. The surveying officer shall decide on the best compromise between making use of existing constructional materials and clearing the the immediate area of obstructions.

1. The spherical volume around the site must be cleared of all obstructions to a radius of 5 NU using a Field Net MK12.
2. Whenever possible, material cleared from the surrounding volume shall be used in construction of the beacon.
3. Warning Beacons MK 14 shall be positioned at all vertices of a dodecahedron enclosing a sphere of 25 NU radius from the site centre.


1. A class 32 neutron star shall be moved to the site using using a Field Net MK17 and the Navigation Service galactic orbit deviation technique.
2. A type 27 red dwarf star shall be placed in an orbit of 0.1 NU around the neutron star and allowed to stabilise.
3. The orbital period of the binary combination shall be recorded after 25 orbits of the red dwarf.
4. The red dwarf's mass shall be increased until it reaches the calculated level required for the correct beacon starting frequency.
5. The red dwarf's orbit shall be reduced to .02 NU and allowed to stabilise.
6. The orbital period shall be checked to see if it agrees with the calculated figure derived in 4.
7. Corrections to the mass of the red dwarf shall be carried out before proceeding to step 8.
8. The red dwarf's orbit shall be reduced to 0.001 NU and allowed to stabilise.
9. The stability of the binary pair shall be checked to see if it agrees with the calculated figures.
10. The red dwarf's orbit shall be reduced until the correct initial operating frequency is obtained.
11. The orbit decay rate shall be monitored for 50,000 orbits of the red dwarf.
12. The red dwarf's orbit shall be readjusted using Pressor Units MK4 to restore the initial operating frequency.


1. The beacon's polar diagram shall be plotted using Survey Computer MK61 to check that it is within the permitted limits for navigational beacons.
2. The beacon shall be bombarded with interstellar debris of a mass which is 0.0001 of that of the red dwarf.
3. The frequency of the beacon should not deviate by more than 0.0001 percent.


1. The beacon shall be monitored Using Monitor MK6 at intervals of 1 NU on all navigational routes which will be served by the beacon.
2. The red dwarf's orbit shall be finally adjusted to give the best compromise of signal strengths on the routes referred to in 1.
3. The Warning Beacons shall be removed from the site.


The MK27 type of beacon will not normally require any maintenance throughout its working life. However, if a beacon shows signs of instability which could be a hazard to navigation, the beacon shall be moved to the nearest black hole site and disposed of, and a new beacon shall be built.


No special parts are required because MK27 beacons are constructed from natural materials occurring in the region of the site.


               No. ITEM                  PURPOSE                     QUANTITY 
               1.  Field Net MK17        Stellar transport              1 
               2.  Field Net MK12        Debris collection              1 
               3.  Pressor Unit MK4      Red dwarf positioning          6 
               4.  Beacon MK14           Warning of danger at site     20 
               5.  Survey Computer MK61  Site selection                 2 
               6.  Beacon Monitor MK6    Beacon performance analysis   10

1. The Use of Planetary and Stellar Field Nets and Pressors (7th edition) 
2. Beacon MK14 Operating Manual 
3. Survey Computer MK61 Operating Manual 
4. Beacon Monitor MK6 Operating manual 
5. Navigation Services Dept. Chartspheres (129th edition or later) 
6. Locations of Standard Navigational Pulsar Beacons (18th edition or later) 
7. The current issue of the Journal of Entertainment Signal Sources. (BBC) 
8. Cat Husbandry. (Lister and Rimmer)

1010 words. (c) Wilf James September 1988 Revised for Octarine 21/5/91 and 06/06/96

Copyright (C) W. H. James 1/11/1985
Revised 15/5/91 and 11/06/96
(2689 words)

Wilf James,106 Jarden, Letchworth, Herts. SG6 2NZ, UK. E-mail   wilf dot james at ntlworld dot com This version of my email address is to beat spammer's robots.
Go to Next: To Whom It May Concern Go to Previous: In the After Glows

Return to Story List