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# format auto-updated on access: Mon 27-Nov-2017 11:29:33 +01:00 CREG Journal Contents Newssheet BCRC HeyPhone, Foot & Mouth, Time for a Change. Meetings & News - Field Meetings, Meetings in Ireland, Award for Cave Electronics, Toolkits, Cave Photography Group, Hidden Earth. Administrivia - AGM. Diary Dates. Launch of the HeyPhone The HeyPhone has now been issued by the BCRC to rescue teams. Mike Bedford reports. BCRC HeyPhone - Physical Construction Brian Jopling, 'Jopo', describes the mechanical design philosophy for the HeyPhone and gives some instruction for those intending to build a unit or to use similar techniques for other projects. Update - HeyPhone Circuit Mike Bedford details some minor circuit changes to the BCRC cave radio, now called the HeyPhone, which have been advised by John Hey. Generating & Detecting Bat Calls Developing an ultrasonic bat detector requires experimentation using an ultrasonic sound source, ideally an 'electronic bat'. Stuart France presents a bat sound generator and then a simple yet sensitive audio front-end for a bat detector. Add-ons for the Nicola System A cave radio doesn't have to be a stand-alone piece of equipment. Graham Naylor explains how the Nicola System has been designed with expansion in mind and describes various add-ons. Correction CREGJ 41: A New Rescue Radio - the Electronic Design. Frequency Synthesis: A review Accurate frequency synthesis is needed for many purposes, from low frequency applications such as audio tone generation and stepper motor control, through to UHF radio. David Gibson reviews some common methods of LF frequency synthesis and suggests some methods of building a 'frequency-agile' cave radio. An RF Power Indicator for Cave Radio Transmitters This add-on unit uses an LED or the transceiver loud-speaker to indicate the power level. Another contribution from Jean-Jacques Fauchez translated by John Rabson. DTMF and its Use in Cave Communication DTMF is well-known by telephone engineers and radio amateurs but has been used infrequently in cave communication. Mike Bedford explains what it is and how it can assist in interfacing cave radios to other equipment. Web Watch Peter Ludwig looks at batteries and lighting. Further Reading If a topic in this issue interests you, this 'further reading' list, compiled by David Gibson, may be of use. Cave Surveying by Radio-location - 2 Stuart France provides some practical guidance for those new to radio-location in this useful 'how to' guide. Speleonics We review the ongoing debate on LED lighting. Cave-proofing Video Cameras (part 2) In part 2, underground video photographer Tony Cook gives some guidance on adapting camera housings to support manual focus and exposure control. Using a Scanner as a Digital Camera David Gibson observes that photographing PCBs and small components is much easier with a flat-bed scanner than with a conventional camera. He demonstrates this with a scan of his experimental through-rock channel-sounding equipment. Meet the CREGgies (2) Who are these people we keep reading about in this journal? And what do they look like? Rosy Rabson interviews Brian Pease, John Hey and Richard Rushton. Letters to the Editor Feedback, debate, information & news - our readers have their say.