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CREG Journal 71 (0-24)
This issue has a cover date of June 2008, but was actually published in December 2008.

Newssheet (3)
2009 Cave Technology Symposium, Publication Delays, Refocusing, Future Directions, Diary Dates.

IP Ratings Revisited (4-6)
Mike Bedford delves into the IEC 60529 standard that defines ingress protection (IP) ratings to correct a common misconception. Two methods of protection against the harmful effects of water vapour ingress - pressure equalisation and desiccation - are also described.

Wet & Dry (7)
Ruggedisation, waterproofing & constructional techniques. Column edited by Mike Bedford.

A Caving Light for the 21st Century (8-12)
Stuart France updates his white LED caving lamp design to incorporate new LED, battery and control technology, and also looks at a powerful back-up light.

Web Watch (12)
Peter Ludwig offers yet more links to intriguing items on the Internet.

We Hear (13)
News and events: Mike Bedford brings us the latest to impact the world of cave radio and electronics.

Novel Cave Radio Antenna uses Small Ceramic Tiles (14-15)
Induction loop antennas are often inefficient due to skin and proximity effects, self-capacitance and tuning losses. However, an electric field antenna will generate a magnetic field which, in some circumstances, can exceed the field strength available from a loop antenna of similar mass and power dissipation. The main difficulty is in achieving efficiency at a small size. David Gibson explains how this may be achieved using high-permittivity ceramic tiles.

Wireless in a Coalmine (16-17)
Mike Bedford reproduces an article which was first published in 1922 by an unnamed author with amateur radio callsign 2ZD, which provides an interesting insight into the early days of experimentation in sub-surface communication.

Speleonics (18)
One of the founders of Speleonics magazine, Frank Reid, died 10 years ago. Several subscribers to the mailing list have contributed fond memories, which are summarised by John Rabson.

Letters to the Editor (19)
Reducing Loran, HeyPhone Coils

Cave Technology Symposium 2008 (20-23)
BCRA's second Cave Technology Symposium took place in April 2008. Mike Bedford and Rob Gill review the proceedings with abstracts of each of the presentations.

Unusual Photographic Duotone Processing (24)
David Gibson describes the digital processing of the 2008 Hidden Earth poster, which used a MatLab program to achieve the desired reduction to two ink colours.

The Adventures of GREG (24)
Illustrations by Adrian Higgins with words by Mike Bedford.