OPERATING INSTRUCTIONS

SUMMARY OF MODES

RUN
Normal operation. This mode is selected on power up. The RUN light will flash every time the radio transmits the tide height. The + and - keys can be used to adjust the display to give a reading relative to a datum (usually either Chart Datum or Ordnance Datum).

ZERO
Used to zero the sensor before immersion in the sea.

CAL
Used to calibrate the sensor at a known depth.

DATUM
Used to set the datum to which the tide height is related.

CH
Indicates the radio address channel number. This number is normally fixed and cannot be changed.

TEST
Displays the calibration factors in sequence. Automatically reverts to RUN at the end.

 INSTALLATION

 Secure sensor to a pier leg (or similar fixed object) so it is immersed at all states of tide and swell. Do not exceed the maximum rated depth of the sensor (20m) at the highest tide.

It is recommended that the sensor be protected by installing inside a metal tube of at least 50mm inside diameter. A weight of up to 2kg can be added via a weak line fed through the unscrewable plastic nose cone so that the sensor cable is kept taut. The weak line should break in the event of the weight jamming in the tube.

Connect antenna with coaxial feeder cable and approved connectors. Mount antenna vertically as high as possible so it has a line of sight to the receiver's antenna.

Apply power to the Tide Gauge and switch on.

When first installed the calibration procedure should be carried out.

The sensor must be lifted and cleaned every six months (or sooner if the fouling is extensive). The plastic nose cone must be unscrewed and cleared of any debris or growths.

CALIBRATION

The Tide Gauge is tested and calibrated in standard sea water however it is recommended that re-calibration is carried out in the local sea water as the water salinity could be significantly different.

Only attempt to recalibrate in still sea conditions.

Connect sensor and antenna, apply power and switch on. RUN mode will be selected.

Immerse sensor to allow it to reach the same temperature as the sea water.

Lift the sensor from the sea, keeping it vertical.

Select ZERO mode by pressing the DOWN-ARROW key. Use the + and - keys to adjust the display to read 0.00

Immerse the sensor to an accurately know depth as deep as possible. (Marking the sensor cable with tape at metre intervals is helpful)

Select CAL mode by pressing the DOWN-ARROW key. Use the + and - keys to adjust the display to read the sensor depth in metres.

Now fix the sensor to the required depth as detailed in the installation instructions.

Select DATUM mode by pressing the DOWN-ARROW key. Use the + and - keys to adjust the display to read the actual tide (eg. as given on a nearby tide board).

Select TEST mode by pressing the DOWN-ARROW key twice. After ten seconds the Tide Gauge will store the new calibration factors and revert to the RUN mode. The Tide Gauge is now calibrated.

Technical Details
General

RF Range	400-470MHz
Modulation	Narrow band angle modulation
Channel Spacing	12.5, 25, 50kHz (state with order)
RF Switching Bandwidth	10MHz
TX risetime	<16ms
RX mute lift	<4ms
Audio bandwidth	300-3000Hz
Supply Voltage	8-14Vdc or 5V (state with order)
Operating Temperature	-20 to +60° C
Dimensions	79 x 64 x 15mm exc. connectors
Humidity	95% RH, non-condensing
Shock	BS2011 Part 2.1Ea, 30g 18ms
Vibration	BS2011 Part 2.1Fd Region A, Cat. 4, 10-1000Hz for 1 hour
Acceleration	BS2011 Part 2.1Ga, ±4g any axis
Specification Compliances	ETS 300 086, ETS 300 220, FCC Part 90

Technical Details
Transmitter Section

Frequency Error	3ppm over -20 to +60° C
RF Output	500mW (others available-state with order)
Modulation Level	±2.0kHz at 1kHz
Adjacent Channel	-65dBc
Current Consumption	700mA at 5V (VSWR1.5)

Technical Details
Receiver Section

Frequency Error	3ppm over -20 to +60° C
Sensitivity	0.3uV PD for 12dB SINAD
Selectivity	65dB
Intermodulation	60dB
Blocking	88dB
Mute	Optional
Current Consumption	40mA