Transceiver to 200 300 meters 220706

AllenPitts · July 6, 2022, 8:39pm

Hello Sparkfun forum,

Have developed a device called a KiteMessenger (KM) that ascends the tether of a

single line kite using a sail. When the KM reaches the desired height, say 90

or 100 meters, a 433 mhz transceiver fob button is pushed and the receiver

in the KM sends a signal to an Arduino Beetle that operates a servo. The servo

moves a travel arm which release two rings. One of the rings holds a payload,

a parachuting armadillo or a bag of candy. The second ring releases the sail

which allows the KM to return to the ground. And so the operation can be

repeated.

https://www.kitemessenger.net/KM_WebSit … m_gif.html

The KM works prefectly. The PCB for the receiever, Beetle and servo have been

designed and tested. 3D printing has been developed and months have been spent

designing and creating the sail, the parachute and the mechanics. Several iterations of each

of the main elements of the KM have been created, integrated and tested getting the minor

defects worked out in each iteration.

https://www.allenpitts.com/electronics/ … _x_460.jpg

The plan is to make six of the KMs and take them to the Washington State Kite

festival, the worlds largest kite festival for demo.

One last improvement is considered.

The range of the 433 mhz is 100 meters on a good day. Would like to extend the range

to 150 or 200 meters. The transceiver used in the KM is

https://www.amazon.com/Wireless-Control … 170&sr=8-8

Wireless Relay 12V Long Range Remote Control Switch, Universal 433Mhz RF Transmitter Receiver Mini Remote Relay

in Latched Module for Home Use and More DC 3.7V 4.5V 5V 6V 7.4V 9V 12V By BWSS

The description of the Wireless Relay 12V Long Range Remote Control Switch… says the range is 3280 feet, 1009 meters.

And the KM transcevier has been tested to 200 meters successfully. On the ground. But with the KM up in the air

beyond about 90 to 100 meters the response is spotty. My knowledge of RF engineering is limited

but reserach indicates that on the ground the radio wavwes are bouncing off the ground

and other objects on the ground. But up in the air, with nothing to reflect off of, the signal

is given to dissapation.

Research has led to considering the RFM69HCW Wireless Transceiver - 915MHz

https://www.sparkfun.com/products/13909

Would like to stabilize with SparkFun as the electronics supplier because

Have done business with SparkFun in the past withh good success and excellent tech support
Have no prejudice against Pacific Rim suppliers but communications and shipping

have been problematic in the past.

The KM currently uses Arduino technology (DFRobot DFR0339 ‘Beetle’) and SPI which

would make and adaptation fairly simple.

The question is: the BWSS transceiver has a transmitter fob and a receiver PCB. The RFM69HCW

is called a transceiver. So is there a transmitter and a receiver on the RFM69HCW? Would

a system like the KM have a RFM69HCW on the ground and a RFM69HCW up in the air also.

How does one cause the transmitter part of the RFM69HCW send a signal to the receiver

element of the RFM69HCW?

Thanks.

Allen Pitts

Dallas Texas

jremington · July 6, 2022, 11:27pm

So is there a transmitter and a receiver on the RFM69HCW?

Yes

Would a system like the KM have a RFM69HCW on the ground and a RFM69HCW up in the air also.

Yes

How does one cause the transmitter part of the RFM69HCW send a signal to the receiver element of the RFM69HCW?

It is done programmatically. You will need an Arduino or similar MCU on each end. Example code for various types of transmissions is provided with the library you choose to use with the MCU+transceiver.

But the much cheaper option is to extend the wireless range of the setup you already have by using a decent antenna. For 433 MHz, a very simple dipole antenna about 34 cm from tip to tip can give over 2000 feet range, if there is clear line of sight.

See the photo attached below for an example. One inner end of the dipole is attached to ANT, the other to GND, on both transmitter and receiver. For best range, the two dipoles should be parallel. The antennas are simple to make, but verify range on the ground before flight!