7815

Sonardyne UK (Head Office) T. +44 (0) 1252 872288 F. +44 (0) 1252 876100 E. sales@sonardyne.com www.sonardyne.com Datasheet TZ/OBC Transponder Description Designed to work with Sonardyne’s TZ/OBC acoustic positioning system, the Type 7815-000-06 transponder enables the positions of seismic hydrophone positions to be accurately and efficiently determined. Standard features include a depth rating of 500 metres, a unique acoustic ‘address’ enabling thousands of units to be laid in a single deployment and automatic battery voltage monitoring to allow users to better plan their maintenance schedules. Key Features • Versatile, low cost transponder • Depth rated to 500 Metres • Provides fast and efficient positioning of OBC cables • Compact and rugged design • HF frequency band from 35-55kHz • Alkaline battery packs give up to 18 months listening life • Optional RFID tags for asset tracking Prior to deployment from a cable lay boat, the transponders are attached to the seismic cable at each ground station, typically every 50 metres. Once the bottom cable is laid, the acoustic system measures the ranges from the surface transceiver to the transponders to enable their exact positions to be established. This positioning process can either be conducted while laying the cable or later while shooting. In OBC operations using a ‘squirter’ cable deployment system, ‘carapaces’ are available that provide a fast and secure means of attaching transponders to the cable. The carapaces are manufactured from tough plastic that encapsulates the transponder and optional RFID asset tracking tag, clamping it securely to the cable whilst protecting it from the high cable deployment and recovery speeds. The transponders are small and lightweight and have been proven to be able to withstand the demanding and varied operational environment of OBC and TZ surveys. The carapace design which is now in use with many crews around the world has been proven to be easy to fit and reduces long term maintenance when compared with traditional tie-wrap and tape methods. The low profile shape of the carapace also reduces the risk of snagging and as it is acoustically ‘quieter’ in the water, creates less noise interference down the cable. Sonardyne UK (Head Office) T. +44 (0) 1252 872288 F. +44 (0) 1252 876100 E. sales@sonardyne.com www.sonardyne.com Specifications TZ/OBC Transponder Feature Depth Rating Operating Frequency Range Source Level Receive Sensitivity Number of Unique Addresses Switch On Battery Life Mechanical Construction Dimensions (LxDia) Weight in Air Weight in Water Deck Unit . Type 7815 500 Metres HF (35–50kHz) 184-187dB 105-115dB re 1µPa @1m 3609 (Field Programmable) Continuously operating (No On/Off switch) Alkaline: 18 months Plastic and Aluminium Alloy (Anodised) 442mm (17.4”) x 63mm (2.4”) 1.11kg 0.20kg Type 7967-000-02 (Includes transducer and 10 metres of cable) Specifications subject to change without notice - 10/2006