ACCESSORIES STINGRAY STANDARD HOW THEY WORK
This is the basic dual alarm, dual rangeunit with LED display only. Very simply, they make a noise and measure the echo. Knowing that sound travels at 144 metres a second through water allows us to calculate the depth by measuring the interval between the sound being made and the echo being heard. The NASAStingray Echo sounders have a transducer with a high quality Lead Zirconate Titanate Piezodisc crystal which creates ultrasonic ‘sound’pulses at a frequency of 150 kHz (imperceptible to the human ear). These pulses pass through the water and bounce back off the bottom. The returning echo pulse is then sensed by the transducer crystal. On these rotary flashing LED type sounders, a pulse is generated as the LED flashes at the 12 o’clock position. The rotor arm is calibrated to run at a speed whereby when it flashes on receiving the returned pulse this flash will be in the correct position on the dial to indicate the correct depth. STINGRAY TWIN
Dual alarm, dual range sounder with digital LCD depth readout in addition to the flash- ing LED display. FEATURES
The NASAStingray Echo Sounders come in a slimline case with an easy to read extra bright LED display on a 4 inch dial. They both have a dual audible alarms for shallow and deep water which can be set to give a reliable anchor marine watch. Both sounders can be set for two ranges either 1-25 metres or 1-100 metres, and are simplicity itself to operate. They come complete with transducer and stirrup mounting bracket and only require connection to the ships 12v power supply. STINGRAY ECHO SOUNDER Stirrup mounting bracket for ?Weatherman ?Clipper navtex ?AIS Boat radar TECHNICAL DATA
Weight (incl. Transducer) – 1Kg.Supply Voltage – Nominal 12v DC Power Consumption – Nominal 120mA Power Output – 100w + Pulse Oscillation Rate:Range A, 0-25 37.5 pulses for sec.Range B, 0-100 7.5 pulses for sec.Transducer – Lead Zirconate Titanate Piezodisc with 7 metres of cable Operating Frequency – Nominal 150 kHz

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