FrSky DHT-U User manual

www.frsky-rc.com
2011/7/14
Instruction Manual for FrSky DHT-U
1. Introduction
1.1 Compatibility
Mode of DHT-U Compatibility
V8 _Mode Non-telemetry receivers (V8FR-HV, V8R7-HV, V8R7-SP, V8R4)
D_Mode Telemetry receivers (D8R, D8RSP, D6FR, D4FR)
1.2 Specification
Operating Voltage Range: 6.0V-13.0V
Operating Current: 50mA
Output Power: 60mW
Resolution: 3072 (>11bit)
1.3 Features
1) All-in-one combination of telemetry module,
in-built display and alarm threshold settings
2) DHT-U can be clamped to the transmitter handle/antenna
3) Show in-flight data via in-built display
4) Capable of setting failsafe during flight
5) Firmware upgradable
2. Screen structures
2.1 Main Screen
FrSky Logo
Data Screen Menu Screen
ModuleID VersionNumber
2.2 Data Screen
FrSky sensor hub, sensors and D8R telemetry receiver are required if information collecting and processing, model
monitoring and data feedback are required.
2.2.1 Data Screen 1
GMT (H/M/S) Fuel Level
Voltage A1 Voltage A2
RSSI
2.2.2 Data Screen 2
GMT (H/M/S)
Acceleration X/Y/Z
Speed RPM Altitude
Note: Press Button “R” to change between absolute altitude and relative altitude.
2.2.3 Data Screen 3
GMT (H/M/S)
Temperature1 Temperature2
Longitude Latitude
2.3 Menu Screen
2.3.1 Menu Screen 1
V8_Mode/D_Mode Bind/Normal/Range Check
Setting Failsafe
Note: When V8_Mode is selected, users will have no access to Setting page or Failsafe page.
2.3.2 Menu Screen 2
A1/A2 Voltage Division Ratio: make sure they are programmed in accordance with those of connected voltage sensors
Unit Set (selectable): Speed (m/s or MPH)
Temperature (Celsius or Fahrenheit)
Alarm Set: A1_1/2, A2_1/2, RSSI_1/2
Below are FrSky default values for RSSI, users can change according to their requirements:
Alarm Than Value
RSSI 1 ＜45
2 ＜42

www.frsky-rc.com
2011/7/14
2.3.3 Menu Screen 3
Press button B to set failsafe during flight, or others to skip.
3. Set Up
3.1 Installation Process
1) Open the transmitter and find out the battery power supply line, GND and PPM signal line.
2) Solder the battery power supply line, GND and PPM signal line to corresponding wires of DHT-U (RED→V+;
BLACK→GND; BROWN→PPM).
3) Clamp DHT-U to the transmitter’s handle or antenna base by provided clamp and screw.
4) Connect the module antenna to DHT-U.
3.2 Bind Procedure
1) Ascertain that the transmitter is in PPM mode. Turn the transmitter off.
2) Turn the transmitter on and enter MENU page, select V8_Mode or D_Mode to work with corresponding receiver you
are using (see compatibility chart above). Select Bind.
3) Connect battery to the receiver while holding F/S button on the receiver. The RED LED on the receiver will flash,
indicating the binding process is completed. Turn off the transmitter and receiver.
4) Turn the transmitter on and enter MENU page, select Normal. Re-connect battery to the receiver. The RED SOLID
LED on the receiver will indicate receiver is receiving commands from the transmitter.
After above steps are completed, both the transmitter and receiver are ready to be used. The bind procedure will not
have to be repeated unless one of the two is replaced.
3.3 Range Check
A pre-flight range check should be done before each flying session. Reflections from nearby metal fences, concrete
buildings or trees can cause loss of signal both during the range check and during flight.
The following steps are to be followed to perform the range check of the model before flight:
1) Place the model at least 60cm (two feet) above non-metal contaminated ground (e.g. on a wooden bench).
2) The receiver’s antennas should be separated in the model and not touch the ground. Place the module antenna in a
vertical position.
3) Turn the transmitter on and enter MENU page, select R-CK, connect battery to the receiver. The effective distance will
be decreased to 1/30 of full range.
4) Walk away from the model while simultaneously operating the controls on the transmitter, confirming that all controls
operate normally to a distance of 1/30 of the full range.
3.4 Signal Loss Indicator and Failsafe Setting
In some special circumstances, such as strong interference, the signal may be lost. When signal is lost in a short
period, the receiver continues to try to search for the transmitter, at the same time it keeps the last command from the
transmitter, until a new command is received.
Failsafe is a useful feature in which all controls move to a preset position whenever the control signal is lost for a
period of time.
Follow the steps below to set failsafe before flight:
1) Bind the receiver first and turn on both transmitter and receiver;
2) Set all transmitter controls to the desired failsafe position;
3) Press briefly the F/S button of the receiver (less than 1 second), the transmitter module will make a long “beep” (for
D8R only) or the GREEN LED of the receiver will flash twice, indicating the failsafe position has been set in the
receiver.
To disable the failsafe function, re-bind the receiver.
Follow the steps below to set failsafe during flight:
1) Bind the receiver first and turn on both transmitter and receiver;
2) Enter MENU page, select F/S to enter failsafe sub-page, press button B to set failsafe at the desired failsafe position
during flight.
Note: If FrSky DHT-U, sensor hub, sensors and LCD-fdd_lite are applied, please upgrade your telemetry
module and D8R receiver with FrSky newly-released ROMs, which can improve the reliability and
stability of data feedback after the transmitter’s reset.
Files are available via FrSky download section: http://www.frsky-rc.com/Downloads.asp?id=91