Edited by Rachel Duncan 4th Edition ISBN 0-907649-91-2 London ...

Communications 67
sizes that are highly suitable for protecting expedition electronics from getting wet,
damaged or covered in dust.
Options for communications are as follows:
7.1 Written messages
A note of your planned route date and time of departure plus your estimated time of return
left with a responsible person, is one of the most useful and inexpensive methods of
communication for relatively short duration journeys.
7.2 Visual and audible signalling devices for use when rescue services are in
close proximity
These devices are cheap and functional and could make the difference between life and
death if carried as a matter of course on any venture.
Mirror Excellent for silent signalling and attracting attention;
Torch
A robust waterproof type, with spare batteries. Use to attract attention
or as signalling device where there may be danger of avalanche
(Visual Morse Code);
Flags/Wands Tied to ski poles to mark snow hole position or to mark a safe route;
Whistles To attract attention;
Flares
7.3 Radio
Smoke, pin-point and rocket flares, each with a specific use are useful
in emergency situations and for indicating wind direction to aircraft.
White flares are of little use in snow-covered regions!
Radio licensing rules vary from country to country and you should be sure that you have
the authority to use any radio in your possession. You may have to use a third party in your
destination country as the applicant for the licence. It is illegal to use Radio amateur
frequencies. Approval can be a long process and you should begin at least a year in
advance. Some countries will not allow the use of portable satellite equipment or may
restrict its operation in ports.
7.3.1 High frequency (HF) short wave radio and very high frequency (VHF)
HF (short wave) radio has virtually unlimited range, subject to ionospheric conditions,
power, aerial efficiency and operator experience.
The 10W crystal set Spillsbury SBX11 now being superceded by the Paracomm
PCX250 is probably the most widely used HF radio for polar travellers. We have used
Racal PRM 40XX series radios and Yeasu FT70G Portable commercial HF radios. These
alternatives work very well and have specifications suitable for polar use. The polar
communications expert Laurence ‘Flo’ Howell has made very lightweight HF radios for
polar expeditions under the brand name CAVU communications.