Difference between revisions of "FrSky DHT RSSI configuration"

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(Created page with "The FrSky DHT is a flexible and relatively powerful 2.4 GHz transmitter. The kit comes as a DIY package with an RP-SMA connector which makes it easy to switch antennas. The commu...")
 
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The FrSky DHT is a flexible and relatively powerful 2.4 GHz transmitter. The kit comes as a DIY package with an RP-SMA connector which makes it easy to switch antennas. The communication is two-way allowing for both Tx and Rx signal strength indication (RSSI).  
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The FrSky DHT is a flexible and relatively powerful 2.4 GHz transmitter. The kit comes as a DIY package with an RP-SMA connector which makes it easy to switch antennas. The communication is two-way allowing for both Tx and Rx signal strength indication (RSSI).  The ACCST system shifts 80 channels around hundred times per second in the 2.4GHz band, similar to FSK.
  
I will use the D6FR receiver in this setup.
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I will use an D6FR receiver in this setup.
  
 
== Serial adapter ==
 
== Serial adapter ==
 
To connect to the transmitter you need a USB-to-serial adapter. FrSky makes one with the necessary pin-header.
 
To connect to the transmitter you need a USB-to-serial adapter. FrSky makes one with the necessary pin-header.
  
[[Image:frsky_usb_cable.jpg]]
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[[Image:frsky_usb_cable.jpg|300px]]
  
 
Plug the black header into the corresponding four pins on the transmitter. Power will be provided by the USB-port.
 
Plug the black header into the corresponding four pins on the transmitter. Power will be provided by the USB-port.
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The DHT provides a serial data port for configuration of the alarms for the RSSI and the two analog inputs. Download the [http://rc-miskolc.emiter.hu/index.php?option=com_content&view=article&id=114:frsky-setup-program&catid=35:tech&Itemid=113 3rd-party configuration program] and the required [http://www.frsky-rc.com/download.asp drivers].
 
The DHT provides a serial data port for configuration of the alarms for the RSSI and the two analog inputs. Download the [http://rc-miskolc.emiter.hu/index.php?option=com_content&view=article&id=114:frsky-setup-program&catid=35:tech&Itemid=113 3rd-party configuration program] and the required [http://www.frsky-rc.com/download.asp drivers].
  
[[Image:frsky_config.png|400px]]
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[[Image:frsky_config.png|500px]]
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== Antenna testing ==
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To get an idea of how well the different set of antennas would perform, I swapped the antennas one by one and recorded the Tx and Rx values from the configuration application.
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* Transmitter:  FrSky 2dbi rubber duck antenna
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** Receiver: FrSky 2dbi rubber duck antenna - RSSI Tx: '''99''' - RSSI Rx: '''99'''
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** Receiver: Dipole 33 mm wire antenna - RSSI Tx: '''99''' - RSSI Rx: '''99'''
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** Receiver: Dipole 30 mm wire antenna - RSSI Tx: '''99''' - RSSI Rx: '''99'''
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** Receiver: Generic Wifi whip antenna- RSSI Tx: '''99''' - RSSI Rx: '''99'''
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* Transmitter: Generic 2.4 GHz 14 dBi patch antenna
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** Receiver: FrSky 2dbi rubber duck antenna - RSSI Tx: '''99''' - RSSI Rx: '''99'''
 +
** Receiver: Dipole 33 mm wire antenna - RSSI Tx: '''99''' - RSSI Rx: '''99'''
 +
** Receiver: Dipole 30 mm wire antenna - RSSI Tx: '''99''' - RSSI Rx: '''99'''
 +
** Receiver: Generic Wifi whip antenna- RSSI Tx: '''99''' - RSSI Rx: '''99'''

Revision as of 19:36, 12 August 2012

The FrSky DHT is a flexible and relatively powerful 2.4 GHz transmitter. The kit comes as a DIY package with an RP-SMA connector which makes it easy to switch antennas. The communication is two-way allowing for both Tx and Rx signal strength indication (RSSI). The ACCST system shifts 80 channels around hundred times per second in the 2.4GHz band, similar to FSK.

I will use an D6FR receiver in this setup.

Serial adapter

To connect to the transmitter you need a USB-to-serial adapter. FrSky makes one with the necessary pin-header.

Frsky usb cable.jpg

Plug the black header into the corresponding four pins on the transmitter. Power will be provided by the USB-port.

RSSI configuration

The DHT provides a serial data port for configuration of the alarms for the RSSI and the two analog inputs. Download the 3rd-party configuration program and the required drivers.

Frsky config.png

Antenna testing

To get an idea of how well the different set of antennas would perform, I swapped the antennas one by one and recorded the Tx and Rx values from the configuration application.

  • Transmitter: FrSky 2dbi rubber duck antenna
    • Receiver: FrSky 2dbi rubber duck antenna - RSSI Tx: 99 - RSSI Rx: 99
    • Receiver: Dipole 33 mm wire antenna - RSSI Tx: 99 - RSSI Rx: 99
    • Receiver: Dipole 30 mm wire antenna - RSSI Tx: 99 - RSSI Rx: 99
    • Receiver: Generic Wifi whip antenna- RSSI Tx: 99 - RSSI Rx: 99
  • Transmitter: Generic 2.4 GHz 14 dBi patch antenna
    • Receiver: FrSky 2dbi rubber duck antenna - RSSI Tx: 99 - RSSI Rx: 99
    • Receiver: Dipole 33 mm wire antenna - RSSI Tx: 99 - RSSI Rx: 99
    • Receiver: Dipole 30 mm wire antenna - RSSI Tx: 99 - RSSI Rx: 99
    • Receiver: Generic Wifi whip antenna- RSSI Tx: 99 - RSSI Rx: 99