433 Mhz Transmitter/Receiver for Drone Drop

Thread Starter

allenpitts

Joined Feb 26, 2011
153
Hello ACC RF Forum,

Actually the project is not a drone drop its is a kite messenger but
there seem to be a lot more people interested in drone drops so it
seemed that would be a better title.
The project is a kite messenger.
Kite_messenger_w_sail_210731.jpg
The kite messenger in the drawing is mechanical which causes problems. An electronic version of the kite
messenger has been developed and tested using the Top Racer Drone Clip.

Top_Race_Drone_Clip_210921.jpg

Have shown this to some kite buddies and kite shops and I am interested in cutting Top Racer out
of the deal and doing the electronics and 3-D printing.
A device for the release mechanism has been found which works well.
EFLA405.jpg

So now a receiver and transmitter are needed. I think this will work
WayInTop+433Mhz_Rcvr_Transmttr_210921.jpg
I believe what is left is to
1. Make sure the signal from receiver will work with EFLA405 Payload Release
2. A power source and a switch for for the receiver. The one in the
Drone clip looks like this
Reciever_Battery_3_7_volts.jpg
Can't find specs on the the receiver so not sure that will work.
3. A power source, power switch and momentary switch for the transmitter.

Also operational indicator LEDs for the transmitter and receivers would be nice.

Have looked for knowledge on this on the AAC forum and the Internet
and most of what was found was how to make the rcvr/transttr work
with Arduino. But it seems that would be overkill since there doesn't
seem to be a need for a microcontroller.

Any help guidance would be much appreciated.

Thanks.

Allen in Dallas
 

DickCappels

Joined Aug 21, 2008
8,000
1) 433 MHz, at least in the U.S. is not intended for more and a couple of seconds per hour of transmission as it is heavily used for remote controls.

2) Super Regen receivers are very sensitive and with decent modulation and coding, should work fine.

3) What is a Kite messenger?
 

KeithWalker

Joined Jul 10, 2017
2,055
Be aware that a coded signal is essential because 433MHz is used for most car electronic door locks and garage door openers. I tried using a similar transmitter and receiver for a short range radio controlled model vehicle but there was far too much interference to make it practical. The 315MHz version may be less prone to interference.
 

djsfantasi

Joined Apr 11, 2010
7,936
Be aware that a coded signal is essential because 433MHz is used for most car electronic door locks and garage door openers. I tried using a similar transmitter and receiver for a short range radio controlled model vehicle but there was far too much interference to make it practical. The 315MHz version may be less prone to interference.
@allenpitts

And hence, you might find that need for a microprocessor… To encode and decode messages to prevent accidental triggering from other 433MHz transmitters in the area.
 

Thread Starter

allenpitts

Joined Feb 26, 2011
153
Hello Dick Cappells, Keith Walker and the AAC RF forum,

A kite messenger is a device that has a kite sail that causes it to ride
up the kite string and when it is say, 200 feet up in the air, release two things:
1. A payload. A parachuting Sponge Bob or parachuting bag of candy for the kids.
2, The sail tether string which allows the sail to flap up against the kite string
and run back down the line so the process can be repeated.
Device test:

Although the device is used on the beach where the only electronic devices
are boomboxes and car radios, to avoid signal interference, it is recommended, it seems, that
the 315 mhz, as opposed to the 433 mhz transmitter be deployed.
315_Mhz_Super_Regen_Trans_Rcvr_210922.png

What is super regenerative?

Is there any way of knowing if the receiver pictured above will trigger the EFLA405 Servoless Payload Release
with out acquiring all the components, power them up and seeing if they will work?

Where could the plugs that are used to connect the EFLA405 and the receiver and the receiver and the power supply
be found?

Thanks.

Allen Pitts, Dallas Tx

pictured
 

BobTPH

Joined Jun 5, 2013
4,055
If you expect to trigger the release by simply detecting a battery signal at the receiver, I think you will be very disappointed. It will fakse trigger almost immediately.

I have used these modules, and it took heroic effort to make it reliable. All my remote needed was to handle 3 buttons. To get this ti work, I send an 8-bit pattern 3 times and only trigger if I see 3 bytes received and two match one of the button codes. This eliminates fakse triggering, but I still grt many presses mussed, maybe 1 in 10.

Bob
 

KeithWalker

Joined Jul 10, 2017
2,055
Hello Dick Cappells, Keith Walker and the AAC RF forum,

A kite messenger is a device that has a kite sail that causes it to ride
up the kite string and when it is say, 200 feet up in the air, release two things:
1. A payload. A parachuting Sponge Bob or parachuting bag of candy for the kids.
2, The sail tether string which allows the sail to flap up against the kite string
and run back down the line so the process can be repeated.
Device test:

Although the device is used on the beach where the only electronic devices
are boomboxes and car radios, to avoid signal interference, it is recommended, it seems, that
the 315 mhz, as opposed to the 433 mhz transmitter be deployed.


What is super regenerative?
A regenerative circuit is an amplifier circuit that uses positive feedback. Some of the output is routed back to its input so as to add to the input signal almost to the point of oscillation, greatly increasing the amplification.


[/QUOTE]
Is there any way of knowing if the receiver pictured above will trigger the EFLA405 Servo-less Payload Release
with out acquiring all the components, power them up and seeing if they will work?
[/QUOTE]

There are so many factors involved in this project that I seriously recommend that you do acquire at least one set of components to test on the bench. That way, any unforeseen problems can be eliminated before you test it in the field. The chances of success are very high with this project.

[/QUOTE]
Where could the plugs that are used to connect the EFLA405 and the receiver and the receiver and the power supply
be found?
[/QUOTE]

The pins on the transmitter, receiver and payload release are all 0.1" pin spacing. Most electronic suppliers stock a whole range of connectors that would do the job.

The EFLA405 Servo-less Payload Release is designed to work with a PPM 5VDC radio control receiver. You will need to generate a suitable train of positive pulses to operate it. The pulses are spaced approximately 18mS apart and have a pulse with of from 1 to 2mS to operate it between open and closed. This could be done very easily using an Arduino uno, micro, mini or even a ATTiny85.
 
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