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Cetaceans use inaudible ultrasonic clicks to communicate and locate prey. The C-click detector takes the inaudible high frequency ultrasound and converts it to frequencies between 100 Hz and 12 kHz, which are in the range of human hearing. The detector can be tuned to receive a range of frequencies from different dolphin species, from 15 kHz to 130 kHz. Using the C-click, most toothed cetaceans can be heard up to 1 km away, and porpoises up to about 100 metres.By simply lowering the C-click hydrophone into the water, you can listen to dolphins even when they cannot be seen. Clicks can be heard through a loudspeaker or through earphones and can be recorded. The sounds provide information about cetacean behaviour: for example, clicking is heard while the dolphins are travelling and buzzing (very fast click trains) is audible when they interact and when they hunt prey. This low cost instrument uses our POD ultrasound transducer technology, coupled with a new frequency converter that reduces the click frequencies to make them audible to the human ear. It has many applications for acoustic researchers, cetacean conservation projects, whale watching boats, sound recordists, yachtsmen and kayakers. Features
Using the C-click cetacean click detectorBatteriesFour AAA alkaline or rechargeable batteries are required: the detector works equally well with both types. Alkaline batteries give very long life, while modern rechargeable cells - especially NiMH - are a more environmentally friendly alternative. Note: Make sure the detector is switched OFF when changing the batteries. CheckingThere are many common sources of ultrasound - for example, jangling keys or rustling newspapers - which produce interesting and different responses. Any of these sources can be used to check that the detector is working. Start with the volume half way and set the frequency control to 40 kHz. In the FieldWhen looking for cetaceans, set the frequency according to the species you're looking for:
Once cetaceans are detected, the frequency control can be fine-tuned to get the best signal. If there are two relatively close frequency settings that give similar signals, always choose the lower one*. The detector only receives ultrasound, it does not transmit anything that will disturb the cetaceans. The only output is the audible signal from the loudspeaker. *Heterodyne detectors produce the difference between the cetacean click frequency and the local signal. If the cetacean click frequency is below the local signal frequency, a fall in the click frequency will result in a rise in the pitch of the audible signal - because the difference will be greater. This is an inversion of the frequency spectrum. If the click frequency is above the local signal, a fall in the click frequency will reduce the difference and so produce a fall in the audible signal - so the frequency spectrum is the right way round.
Price£150 + VAT. Prices are for advanced payment only. Post and packing is free in the UK. For delivery outside the UK, please email us for a quotation. DeliveryC-click hydrophones in stock will normally be delivered within 2 weeks of ordering. PurchasingIf you're in the UK, you can buy now, using a credit card or PayPal, by clicking the button below. NotesThe C-click is not recommended for use in scientific experiments where sound intensity has to be measured. The sensor is manufactured to withstand pressure down to 15 metres of depth, and must not go below this. Do not submerge the C-click housing in water or allow it get wet.
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