KAVAN R8 - User manual

From KAVAN RC Wiki
Other languages:


Congratulations on your purchase of the KAVAN R8 advanced 8-channel telemetry receiver. It operates on a 2.4GHz simultaneous dual-frequency transmission system Twin 2.4GHz. It has 8 high-precision PWM channels and 16 or 24-channel modes using S.BUS. Two detachable antennas with IPEX4 connectors provide full signal strength over a range of up to tens of kilometres. It is especially ideal for gliders, but you can also use it for other various models. With redundancy support, it can be connected as a primary receiver via S.BUS. With the Twin 2.4GHz protocol, both receivers work fully simultaneously in this connection. Thanks to the F.BUS connection option, you can also pair it quickly and easily to several different telemetry devices, providing bidirectional data transmission via a single cable.

It features advanced interference suppression for reliable, stable signal transmission across the entire range. Smart transmission system matching speeds up pairing. The black box function stores essential flight data. Receiver operating statuses are indicated by an LED indicator. Smart pairing allows firmware updates wirelessly.

It is also available in a variometer-equipped version, which provides more accurate and faster measurement and transmission of altitude and vertical speed data. It also allows instant audio feedback from the variometer for Twin 2.4GHz transmitters.

If you have any questions about the R8 receiver and its operation, please contact the technical and service staff of KAVAN Europe s.r.o. by e-mail (info@kavanrc.com for general technical information, servis@kavanrc.com for service) or by phone (+420 466 260 133 for general technical information, +420 463 358 700 for service), during working hours 8am–16pm, Monday to Friday).

Technical specifications

  • RF transmission: Twin 2.4 GHz
  • Dimensions: 54×20×10 mm (L*W*H)
  • Weight: 9.8 g
  • Operating voltage: 3.5–10 V (supply voltage min. 2.8 V)
  • Operating current: 80 mA at 5 V
  • Vario - vertical speed measurement range: ±10 m/s
  • Vario - altimeter range and resolution: -700 m to 10.000 m, 0.1 m
  • External voltage measurement range via AIN2: 0–35 V
  • Antenna connector: IPEX4
  • Compatibility: Twin 2.4 GHz
  • Max. radiated power: < 20 dBm
  • Operating frequency: 2.400–2.4835 GHz


  • Increased protection against RF interference and more stable RF transmission
  • Simultaneous dual-frequency Twin 2.4GHz transmission system with smart pairing
  • Features of the black cabinet
  • High maximum operating range
  • Wireless firmware updates (OTA)
  • 8 high-precision PWM channels
  • S.BUS output port with 16/24 channel mode)
  • S.BUS input port (with support for redundant connection of 2 receivers)
  • F.BUS / S.Port

Status light (ACCESS)

Green Red Status
On On Registering
Blinking Blinking Registration complete
On On Pairing
On Off Pairing complete
On Off Working properly
Off On Fail-safe mode

Registration and pairing

Before using your receiver you must first register it.


1. Start the registration process by selecting [Register].

2. A window will appear with the message "Waiting...." with a repeating voice message "Register".

3. Hold down the pairing button on the receiver and switch it on. Wait for the red and green LEDs to light up. The RID and UID can be set at this stage:

RID: This is the unique identifier of the transmitter. It can be changed to the same/own code to use the Smart share feature for model sharing (if you want to share models and own multiple transmitters, or if you share models with other modellers, you must have the same RID set on those transmitters). The RID is the transmitter data (Owner Registration ID) written into the receiver's memory. If two transmitters have the same RID, you can easily share models including receivers between them using the Smart share function.

RX name: the naming of the receiver is done automatically when the receiver is paired for the first time. This name can be changed at any time. This is useful when using more than one receiver, e.g. to remember the settings of the receivers, e.g. RX4R1 is for CH1-8 or RX4R2 is for CH9-16 or RX4R3 is for CH17-24.

UID: is used to distinguish multiple receivers used simultaneously in one model. A default value of 0 can be left for a single receiver. If more than one receiver is to be used in one model, the UID must be changed, usually 0 for CH1-8, 1 for CH9-16 and 2 for CH17-24. Note that this UID cannot be read back from the receiver, so it is a good idea to tag the receiver.

4. Press the [Register] button to complete the settings. The "Registration OK" dialog box will appear. Press the [OK] button to continue.

5. Turn off the receiver. This registers the receiver. However, you still need to pair it with the transmitter to use it.

Caution: Do not pair with an electric motor connected or with an internal combustion engine running.


Receiver pairing allows a receiver registered in phase 1 to be paired with one of the transmitters. After that, the receiver will only communicate with that transmitter unless you pair it with another transmitter. Before using the transmitter for the first time, you must check the range of the transmitter!

1. Turn off the power to the receiver.

2. RX 1 [Pairing]: Select [Pairing] to start the pairing process. Every few seconds, a "Pairing" voice alert will sound to confirm that you are in pairing mode. A pop-up window will display the message " Waiting for receiver...".

3. Switch on the receiver without holding the F/S pairing button. A window will appear with the message "Selecting Device" and the name of the receiver you have just switched on.

4. Scroll to the receiver name and select it. A window will appear with a message that the pairing was successful.

5. Turn off the transmitter and receiver.

6. Switch on the transmitter and then the receiver. If the green LED on the receiver is lit and the red LED is not lit, the receiver is connected to the transmitter. The pairing of the receiver and transmitter will not need to be repeated unless one is replaced.

• The receiver will only be controlled by the transmitter it is paired to. Other transmitters in its vicinity do not affect its function.

• The name of the selected RX1 receiver will now be displayed next to it.

• The receiver is now ready for use.

• If redundant wiring is required, repeat for receivers 2 and 3.

How to set up telemetry altitude data

  1. Pair the receiver with the built-in variometer sensor to the transmitter.
  2. In the menu MODEL → TELEMETRY select search for new sensors.
  3. The new sensor is found and the [Altitude] should still flash in the list.
  4. Hold down the [Altitude] line to bring up the [Edit] menu.
  5. Now the telemetry data such as [Range] and [Units] of the variometer can be set.

How to switch S.Port/F.Port/FBUS

VF system → RX1 line → [Set]

The body. Port → expand menu and select S.Port/F.Port/FBUS

How to switch SBUS channel mode

VF system → RX1 line → [Set]

SBUS → expand menu and select SBUS-16/SBUS-24

OTA ("Over The Air") firmware updates

Go to [File Manager] and select FW, press enter button, select [Flash RX by int.OTA]. Power on the receiver, select RX, confirm by pressing [ENTER], complete the flash process and [Success] will be displayed on the transmitter.

Wait 3 seconds, the receiver is working properly at this time.

Note: Do not perform the Pairing/Registration process in the near range during a firmware update.
Update the firmware after the receiver is registered (OTA).

Range check

A range check should be made before each flight in case loss of signal is caused by reflection from metal or concrete structures and shadowing of the signal by buildings or trees during flight.

  1. Place the model at least 60 cm on a non-metallic base (e.g. on a wooden bench). The receiving antenna should be in a vertical position.
  2. Enter the ETHOS system, go to "VF system", select the "RANGE" mode and press [ENTER]. In the range check mode, the effective range is reduced to 1/30.

Fail-safe emergency rates

After enabling Fail-safe, there are 3 modes available: No signal, Hold, Custom.

No signal: When the signal is lost, the receiver does not send a control signal to the deflectors on any channel. To use this type, select it from the menu and wait 9 seconds for the Fail-safe setting change to take effect.

Hold: The receiver maintains the deflections as they were before the signal was lost. To use this type, select it from the menu and wait 9 seconds for the Fail-safe setting change to take effect.

Custom: The receiver maintains the deflection value on all channels as you pre-select it. Select the Fail-safe setting menu. Switch from Disconnect/Hold/Not set to "Custom". Select the channel for which you want to set fail-safe deflections and confirm the selection. Then set the deflections on each desired channel and confirm the selection. Wait 9 seconds for the Fail-safe setting change to take effect.

Note: If Fail-safe is not set, the model will always operate with the last functional state of the channels before signal loss. This could cause potential damage. If Fail-safe is disabled on the RF side of the module, the receiver will go into default Hold mode. Do not set the Fail-safe mode for the SBUS port to No Signal mode because the signal would be continuously transmitted, set the SBUS port to Hold or Custom mode.

Warranty and post-warranty service

All KAVAN® electronic products are covered by a 2-year warranty covering all manufacturing defects and faults. When claiming within the warranty period, please always present a copy of the proof of purchase with the product and provide service personnel with as detailed and complete information as possible about the defect found, your usage and other information that will facilitate the assessment of the claim and speed up its settlement.  Please make your claim at the shop where you purchased the product. If this is not possible, you can contact KAVAN Europe s.r.o. directly:

KAVAN Europe s.r.o. | Doubravice 110, 533 Pardubice | Czech Republic | +420 466 260 133 | info@kavanrc.com

Recycling (European Union)

Electrical equipment bearing the crossed-out bin symbol must not be disposed of in normal household waste but must instead be taken to a specialised collection and recycling facility. In EU (European Union) countries, electrical equipment must not be disposed of in normal household waste (WEEE - Waste of Electrical and Electronic Equipment, Directive 2012/19/EU). You can take unwanted equipment to your nearest collection or recycling centre. The equipment will then be disposed of or recycled safely free of charge. By handing in your unwanted equipment, you can make an important contribution to protecting the environment.

EU declaration of conformity

KAVAN Europe s.r.o. hereby declares that the radio equipment type R8 and other equipment supplied with it are in compliance with Directive 2014/53/EU. The full text of the EU Declaration of Conformity is available at the following website: http://www.kavanrc.com. This 2.4GHz radio equipment can be used without prior registration or individual approval in all countries of the European Union.