Rowing & Sports Performance Monitoring Support

Cox-Box Installation Instructions

Before starting, please take a minute to check that you received everything you paid for. A compete Cox-Box system contains the following:

carrying case
Cox-Box control unit
speakers (as ordered)
mounting cup
harness, with sensor installed
"Do's and Don'ts" card
hardware pack

1, 2, or 3

The hardware pack contains:

#8 x 3/4" stainless steel panhead screws
#8-32 x 1/2" machine screws with nuts and washers
#6 x 1/2" stainless steel panhead screws
#6 x 1/2" brass flathead screws
magnet assembly
cable clips



1. Refer to the figure below. Note the position of the sensor - it should be close to the center of the seat travel and it MUST be at right angles to the length of the shell. It is NOT necessary for the sensor and magnets to be centered between the rails as shown in FIG 1a. They may be positioned as shown in FIG 1b for instance. It is essential however that the magnets pass directly over the sensor.

PLEASE NOTE: The sensor MUST be at the center of the seat travel. If the magnets are too close to the sensor at either end of the seat travel, the Cox-Box may indicate ONE HALF OF THE CORRECT STROKERATE. Not everyone uses the full range of motion of the seat, and the seat travel may not be centered.

It is essential that the holes in the magnet assembly pass directly over the holes in the sensor. The dashed horizontal line indicates the correct alignment.

2. The spacing between the stroke sensor and the magnet assembly is critical. Because the distance between the seat plate (to which the magnets will be attached) and the deck (to which the sensor will be attached) varies considerably from shell to shell, you should start by measuring this distance. Refer to the figure below.

he spacing between the magnets and the sensor is important. Too large a value could cause improper operation of the strokemeter - too small a value could cause the magnet assembly to strike the sensor.

3. If the distance measured as in the figure above GREATER than 1 and 1/8" then you will need to make a shim of appropriate thickness. You may choose to shim the sensor or the magnets, whichever is easier. DO NOT use any magnetic material for your shim.

4. If the distance measured as in the figure above is LESS than 7/8" then you will have to remove material from either the seat or the deck - fortunately this rarely if ever happens! If it does, consider mounting the magnets on the upper side of the seat plate.

5. Uncoil the wiring harness and lay it out in the shell. If you are installing your Cox-Box in a sectional shell, the harness should be equipped with a plug/receptacle break in the wiring which should be within a foot of the section bulkheads.

NOTE: You can install the sensor and magnets more or less permanently by using the 3M VHBTM (Very High Bond) tape supplied. Should you wish to make a temporary installation, use the screws provided and DO NOT peel away the protective layer from the VHB tape.


6. Check that the sensor cable is routed conveniently.

7. Use a solvent to clean the area of the deck to which you will attach the sensor. This is essential for a good bond. Peel away the protective layers of the VHB double sided tapes, and firmly press the sensor onto the cleaned area of the deck.

8. Using two cable clips provided, secure the sensor wire. We suggest that you do not rely entirely upon the small adhesive area of these clips, but use the #6 x 1/2" brass flathead screws provided to fully anchor the clips. The cable can be removed if necessary without removing the clips.


1. Remove the stroke seat. Inspect the seat plate to see if there is an area which will allow you to use the #8 machine screws to secure the magnet assembly. If there is not, don't worry - the VHB double sided tape is very strong. If there is, you have the option of making a temporary installation using the #8 machine screws and leaving the protective layer on the tape.


2. Use a solvent to clean the area to which you will attach the magnets. This is essential if a good bond is to be obtained.

3. Determine the exact location of the magnet assembly on the seat plate. Peel away the protective layer of the VHB double sided tape and install the magnet assembly.

4. Return the stroke seat to its slide and check that the clearance between the magnet and sensor is no more than 3/8 "(refer to the figures above). Check also that the magnets pass directly over the sensor (refer to the figure above).


The NK loudspeakers are assembled by us and they have been waterproofed by us using silicone based protective coatings. Neither rain, fresh water, nor salt water will do any harm but we strongly recommend that you install and angle the speakers so that any water which gets in can run out again. The plug in feature of NK speakers makes replacement very easy.

1. Install the speakers using the #6 x 1/2" panhead screws and the metal bracket on the speakers, or by using the DUAL-LOKTM which is on the back of the speakers. We have supplied 6 screws; you will not use all of them unless you are installing a three speaker system. If using DUAL-LOK be sure to clean the area where you will attach the speakers with the alcohol wipe provided. Then remove the backing from the three pieces of DUAL-LOK on the speaker (leave attached to the speaker) and press the whole assembly in place. You can leave the metal bracket on in case you decided to use it later. Remember it is best if the speakers are angled downward to let water run out.

2. Connect the speakers to the wiring harness. Use the remaining six cable clips to secure the wiring harness. We suggest you use the #6 x 1/2" brass screws supplied to fully secure these clips.


1. The mounting cup should be installed so that the display of the Cox-Box will be parallel to the water. It is NOT necessary to angle the Cox-Box. Decided where you want to secure the cup and mark the surface using the cup as a template. Drill two pilot holes for the #8 x 1/2" panhead screws and secure the cup. Do NOT overtighten the screws! If you have a shell with a built in cup it may be tilted. This is OK.


1. With the control unit OFF and the toggle switch set to its RUN (middle) position, connect the large pin receptacle of the wiring harness to the rubber plug on the front panel of the control unit.

2. Connect the microphone. It is not necessary to complete the bayonet connection.

3. Turn the control unit ON. The Cox-Box display should now be on, the clock will NOT be running, the RATE and COUNT windows will be showing 0's and the display light will be on.

4. Push the toggle switch lever down and hold it there 1/2 second. The display should show all zeroes and "READY", "STOP".

5. Slide the seat over the sensor - the clock should start to run and as you continue to slide the seat back and forth the ratemeter and counter will register. Continue to slide the seat for at least 20 seconds then push the toggle switch down ("ZERO"). This stops the timer.

6. Now momentarily push the toggle switch down several times. Each time you push the toggle down the time will increment by 10 seconds (0, 10, 20 ...) and the stroke rate at the selected time will also be displayed. After 1 minute rates are saved every 20 seconds for another 10 minutes.

The last time recalled from memory is the time at which the timer was stopped.

7. Now turn the Cox-Box off then back on again - the memory is NOT lost. To clear memory you must press the toggle switch down and hold it down for 1/2 sec or longer.

8. After clearing memory (see above) move the stroke seat again to start the timer. Flip the toggle switch to "HOLD" this freezes the time display the ratemeter and counter continue to operate. Set the toggle back to "RUN" and the timer will update.

9. Speak quietly into the microphone and adjust the volume. You should hear your amplified voice from the speakers.

10. Disconnect the harness. Plug the charger into an appropriate outlet and connect the plug to the rubber plug on the front panel. The charging indicator lamp (at about 4 o'clock to the plug) should come on to confirm charging.


The operating instructions we normally supply are printed in the Cox-Box System Operation, Maintenance & Troubleshooting Guide. For more comprehensive maintenance instructions please see our Cox-Box Maintenance Kit and the NK Boatman Kit.