How to make 433Mhz rf transmitter work without a microcontroller?

Thread Starter

bouncyboing

Joined Jun 24, 2019
2
Hello. I'm new to electronics and have very little knowledge on the topic, so any help would be appreciated.

I'm trying to use a transmitter to send signal to a receiver to light up/turn off an led, but I need the whole transmitter circuit to be as small as possible. I have seen a few videos online about how the rf transmitter/receiver pair works, but a lot of them has the transmitter connected to either an arduino board or breadboard.

Is it possible to make the transmitter work with just the transmitter, a button, and some batteries?

P.S.
I have not started on this project yet since I have very limited budget as a student.

Thanks in advance.
 

AlbertHall

Joined Jun 4, 2014
9,824
I think the short answer is no, you will need some extra circuitry.
The receivers for ASK (amplitude shift keying) need at least a square wave in. That could easily be provided by a '555 with the button changing the frequency.
The receiver will then need a decoder which could be another '555 wired as a missing pulse detector.
 

MrChips

Joined Oct 2, 2009
21,050
An RF transmitter will transmit a radio signal when activated. The RF receiver will detect the transmission.

The problem is that the received signal will be intermittent and cannot be used to consistently control an LED.
How do you prevent the receiver from being activated by other 433MHz transmitters in the vicinity?

You need some kind of coded command to distinguish between ON and OFF.

A simple solution is to modulate the RF signal with two different AF tones. Now you need to build the receiver that can discriminate between the two AF tones.

The simplest solution is to buy a wireless doorbell from any hardware store and modify it for your application.
 

Reloadron

Joined Jan 15, 2015
5,423
That's what I would do. I have one of these from Amazon and it works just fine and allows momentary or latching action and has 4 channels. They all roll in from China and are small, very small. I use the 12 volt flavor to remotely turn garage lighting on / off. No clue as to actual true range but I have no problem with 75 feet of unobstructed signal path.

Ron
 

Thread Starter

bouncyboing

Joined Jun 24, 2019
2
It seems this is still beyond my current abilities. As much as I'd like to make it myself, I'll go for a ready-made one as most of you suggested. Thank you for all the replies.
 
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