Locating Push Camera Cable Quick Guide
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15. Continue to trace the pushrod cable along the route.
As the end of the pushrod cable is reached, the signal will rapidly reduce. This is to be expected and typically will
happen a meter or two (3-6 feet) from the camera head.
At this point, the signal will start to be distorted, and the depth measurement will be affected. Check for distortion
by raising the locator a known distance such as 300mm (1ft) and check the depth changes by approximately this
amount. If it doesn't, treat the results with caution.
Distortion will also occur at the reel end of the pushrod cable.
If the exact position of the camera is required, switch the sonde on at the control box and use the vloc3-
Cam in the sonde mode to detect the camera head (see section "Sonde Location Mode.")
Sonde Location Mode
The sonde is located at the spring termination end, where it connects to the pushrod cable. When activated in the control module, the
sonde emits a locating signal that the vLoc3-Cam locator can detect and pinpoint.
Sonde screen icons:
1.
Peak signal detector
2.
Signal strength bar graph
3.
Sonde icon
4.
Null point
5.
Frequency selection
6.
Numeric signal level (mirrors the bar graph)
7.
Gain setting
8.
Sonde mode icon
9.
Omni Peak response icon
Method
1. Activate the sonde from the control module. Push the sonde/camera head approximately 10 to 12 feet (3-4m) into the pipe.
2. Switch on the vLoc3-Cam locator and use the Mode key to enter the sonde mode. The sonde and omni peak icons will appear in the
upper left corner of the LCD.
3. Use the "f" key to select the sonde frequency matching frequency of the control module.
Tip
Use a low frequency such as 512 or 640Hz in ferrous pipe material such as is cast iron as low frequencies penetrate metal better than
high frequencies. Also, use low frequencies when locating over re-bar as low frequencies are less likely to jump onto metal structures.
Use higher frequencies such as 32.8kHz when in PVC, plastics, or clay pipes, as this will give steadier results.
4. Hold the locator vertically and stationary with the tip on the ground.
5. If the locator is within the range of the sonde, the screen will appear similar to the one below with an arrow pointing in a particular and
steady direction. The bar graphs on either side of the screen are identical and indicate the signal strength. Use the + and – keys to
alter the receiver gain to keep the signal within the limits of the bar graph.
6. If the bar graph is not steady, it will most likely be because the sonde is not within range. In this case, hold the locator at approximately
45 degrees to the ground and rotate the locator around a full 360 degrees around you.
7. Note the direction of the strongest signal and walk towards it until the bar graph shows a steady signal. Now revert to step five above.
8. Slowly walk in the direction of the arrow.
9. A double circle will appear on the screen. This double circle indicates the position of a null signal. Walk toward it and position it over
the crosshairs of the screen. Now rotate the locator so that the arrow is pointing forward.
