Topcon RC-4, Instruction Manual, Page: 21 / 34

Basic Operation
19
Turn-round operation status display
With the RC-4R, turn-round operation will be displayed as shown below.
Stopping Turn-round operations
Press the [ESC] key to terminate turn-round operation. After the key is pressed, turn-round operation will
continue for a short time before the TS/IS/QS comes to a stop.
Low Power Mode of Laser Beam
When the TS/IS/QS performs a turn-round function at a distance of approximately 30 m from the RC-4R, strong
reflections of the pulsed laser diode (PLD) emission can prevent the TS/IS/QS from searching the prism
correctly. In this case, switch the laser to low-power mode to reduce the intensity of such reflections.
In low-power mode, the range of the turn-round function is shorter than in normal-power mode.(Approx. 50m)
To change the low-power mode
Turn the power ON while holding down the [ESC] key.
A buzzer will sound indicating that the RC-4R is in low-power mode.
To return to normal-power mode, turn the power OFF, wait several seconds, and then turn the power ON again.
Reference : Turn-round motions:
When the turn-round key on the RC-4R is pressed, the pulsed laser diode (PLD) in the emitter produces a laser
beam with a ± 10° cone pattern, refer to “Light Emitting Angle” on page 16.
The RC-4H component of the TS/IS/QS has photo detectors on all four sides (front, rear, right and left), allowing
laser beams to be detected in any orientation. This detection ability extends to approximately ± 30° in the
vertical direction, refer to “Light Detecting Range” on page 17.
Upon detecting laser emissions, the TS/IS/QS aligns toward the RC-4R.
After horizontal alignment, the telescope is scanned vertically in order to target the prism and initiate auto
tracking.
Under certain conditions, the time required for communications can increase to the point
that turn-round operations require a long time to complete, and under certain circumstances
such operations might not even be completed properly. The following conditions can
adversely affect operation:
1) When units are used for communication over long distances or under poor atmospheric
and weather conditions (e.g., in strong direct sunlight; heat refraction such as occurs
near road surfaces and building surfaces on hot days; rain; fog, etc.)
2) When the aim of the RC-4R is set incorrectly, refer to “Light Emitting Angle” on page 16.
3) When communication channel settings, or other settings, of the TS/IS/QS and RC-4R
are not matched or are set incorrectly, refer to “Setting Mode” on page 20.
4) When the TS/IS/QS is located in front of or to the side of glass or some other reflective
surface.
5) When, during turn-round operations, a person, car, or other object obstructs the light
path between the TS/IS/QS and the RC-4R.
6) When the units are used over long distances, the RC-4R is set to low-power mode, refer
to “Low Power Mode of Laser Beam” on page 19.
7) When the dip switch settings on the RC-4R are set incorrectly, refer to “Communication
Baud Rate” on page 21.
8) When the battery status display on the TS/IS/QS is flashing (low battery power)
Ready for communication
Searching
or
(Low Power mode)