sandbox: Journal 132 has gone to press and is due for publication in December 2025
CREG Journal 132 (0-24)
This issue has a cover date of December 2025 and was published on 1 December 2025.

Front Cover (1)
Dr Matt Rowberry installing a novel positioning system for three dimensional fracture displacement monitoring in the British Cave Science Centre. Photo: <span class="author">John Gunn</span>

Contents (2)
List of contents and masthead information.

News and Notes (2)
Spring 2026 Field Meeting, Hidden Earth 2026, CREG Editorial Team.

A Practical Guide to 3D Cave Photography (3-6)
Cave passages provide a wonderful if harsh environment for stereo photography. Here, <span class="author">Michael Perryman</span> provides a simple 'how to' guide, aimed at allowing complete beginners to take their first steps in capturing three-dimensional images.

Detection of Unknown Cavities in Caves Using Infrasound (7-8)
<span class="author">Rafael Grimm</span> describes a new innovative method for the detection of unknown cavities in caves using infrasound.

Stations Transmitting in the VLF Spectrum (9)
Knowing about those radio stations transmitting in the frequency bands used for caving-related applications can be essential. <span class="author">Mike Bedford</span> investigates one such band, namely VLF.

Pinger 2.0: an Updated Transmitter for Radiolocation in Flooded Passages, Part 2 (10-14)
To conclude their discussion of this new radiolocation transmitter, <span class="author">Aren Leishman</span> and <span class="author">Ken Smith</span> turn their attention to constructional details and guidance on how to use the system.

Micro-HeyPhone Modification (14)
<span class="author">Chris Ross</span> describes a Micro-HeyPhone modification to prevent feedback that can occur in some circumstances.

The British Cave Science Centre - an Update (15-16)
Established to provide an open-access research facility for scientists and engineers, the British Cave Science Centre is now seven years old. Here, <span class="author">Andrew C. Smith</span> and <span class="author">John Gunn</span> provide a reminder of the aims and ambitions of the BCSC, outline some recent developments, and stress the ongoing opportunity for technically minded cavers to make a valuable contribution.

Hidden Earth 2025 (17)
<span class="author">Chris Ross</span> provides an overview of the UK's Hidden Earth caving conference, paying particular attention to the technology-related activities.

Building Blocks (18)
The humble relay, old technology, but still going strong! by <span class="author">Tony Haigh</span>.

Tuned Loop Antenna Matching Made Easy (19-21)
<span class="author">Brian Pease</span> describes a simpler alternative to commonly used methods to match low-frequency tuned loop antennas to radios by adding a single capacitor to the tuned loop circuit. Easy equations are given along with methods to measure loop impedance without an impedance meter.

Update (21)
The Technology of Cave Diving Habitats, <span class="author">Andy Pitkin</span>, CREGJ 131, pp. 3-7.

Book Review - Cave Radio (22)
The Radio Society of Great Britain, the UK's amateur radio organisation, has recently published an introductory book on Cave Radio, written by Mike Bedford. <span class="author">Rob Gill</span> takes a look and considers whether this will encourage wider interest in cave radio and electronics.

CREG Field Meeting - Autumn 2025 (23-24)
CREG recently held a very successful field meeting in the Yorkshire Dales as <span class="author">Mike Bedford</span> reports.