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Questions tagged [433mhz]

433MHz is a license-free area of the RF spectrum in many countries. It tends to be restricted to low power and bandwidth but allows simple modulation schemes making it popular for low cost / bandwidth applications such as keyless entry and alarm systems.

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Creating a short signal transmission in HT12E based RF communication

In HT12E we continuously transmit even when the input data pins are not changed.My problem is battery optimisation. I am transmitting only ON/OFF switch state through HT12E based RF module and Since ...
Anandhan A's user avatar
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1 answer
110 views

What is the oscillator in this 433MHz transmitter?

I took this image from ev1527 datasheet. The RF transistor drives the tank circuit to generate rf signal. What is the name of this rf oscillator? Is it a Colpits oscillator? Also there is a project in ...
Zaki's user avatar
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1 answer
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Adding SMA connector to a 433 MHz remote

I need to open a gate from 100 meters distance. This gate uses a 433 MHz rolling code remote. The only option I see, is to connect an active amplifier to the remote using a SMA connector. Those ...
user3161330's user avatar
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1 answer
57 views

Problem to transmit data using FS1000A

My circuit have 4 simple parts. Input voltage is 14.5 so I use two regulator 7805 and 7809 to power supply boards. I use 7805 for WeMos D1 mini (clone) and 7809 to supply power of FS1000A (max input ...
math deaman's user avatar
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60 views

How to design 433 MHz RF with SYN470R?

In this document, I see that 50 Ω of the antenna is mentioned, but what makes me wonder is that in the table below, each strange frequency has a separate impedance, Zin. What is Zin and what does it ...
Nguyễn Tiến Sang's user avatar
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30 views

SemTech SX126x antenna matching

SemTech SX126x, LLCC68. Please, I could not find the component values for a matching antenna at 433 MHz and +22dbm. Do you have a schematic and list of nominal values for this? I was only able to find ...
Tw1nK ''s user avatar
2 votes
1 answer
527 views

Identify RF 433 MHz chip in remote to reproduce it

I've recently bought a ceiling fan (Suilon Cambil) and I wanted to automate it substituting the remote it comes with, with a DIY one connected to Alexa. Main problem is that I haven't been able to ...
david llevat's user avatar
2 votes
2 answers
206 views

How can I receive the bitstream of a 433 MHz remote on PIC16F628A only using timer2?

I'm trying to interface a 433 MHz receiver module with a PIC16F628A, running at 4 MHz from the INTOSC. The idea is that using a generic 433 MHz remote, I could pair it to the uC and toggle some ...
fpp's user avatar
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1 vote
1 answer
492 views

How to change the transmitting frequency of a FS1000A module?

I have tried swapping the 433 MHz crystal on a FS1000A module for an 868 MHz one, since this is the frequency my garage operates at. Now the modified module does not work reliably. I did get it to ...
Jbrimbelibap's user avatar
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0 answers
85 views

Decoding Soil Moisture Sensor 433 MHz

I need to decode soil moisture sensor using RXB6 and ESP32. I tried several libraries; it can get data but not the correct one. Due to my knowledge on this 433 MHz radio, I can't figure out. There's a ...
chamroeun bm's user avatar
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3 answers
1k views

Is it possible to transmit a video over a 433 MHz RF module?

Is it possible in any case to transmit a video over a 433 MHz RF module?
Mohamed Essam's user avatar
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Antenna design for outdoor waterproof sensor

I am designing a low-cost soil moisture sensor with an RF433 radio. I put my sensor in a closed PVC tube for outdoor installation.(SIMILAR TO above image) Without the tube, I can transmit nearly 300 m ...
chamroeun bm's user avatar
1 vote
1 answer
65 views

Why shouldn't I use devices with motor capacitors with my remote controlled power plug adapter? [closed]

In the manual of a remote controlled power adapter (one of those that you plug into a power socket and switch on/off via the 433MHz remote control) it says that you should not use it with devices that ...
RhinoDevel's user avatar
0 votes
2 answers
2k views

Can I extend the range of this 433.92 MHz gate opener by soldering a copper wire to it as antenna?

I have a 433.92 MHz gate opener remote that I would like to be able to control from my phone. In order to do this I have soldered a relay to one of its buttons, which I already have means to trigger ...
Isti115's user avatar
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1 answer
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ETSI standard for 433 MHz

I am really confused about ETSI standards for SRD. I need some ETSI standard which regulates frequency band 433 MHz (433,050 MHz to 434,790 MHz). I found ETSI EN 300 220-1 V3.1.1 (2017-02) - it seems ...
WITC's user avatar
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-3 votes
1 answer
119 views

Problem with using 8 channel 433mhz 12 v relay module to control an overhead crane [closed]

I have recently tried to retrofit an existing overhead crane with a 8 channel 433mhz 12 v relay module with a receiver and a transmitter I bought online. My existing crane already has a button pendant ...
Naveen Gupta's user avatar
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1 answer
643 views

MX-FS-03V 433 MHz transmitter will it function with a coil missing?

I'm planning to make a project using the MX-FS-03V 433 MHz transmitter and the corresponding MX-05 receiver with a couple of Arduinos for short range radio communication. Range will be at most 10 ...
dgnuff's user avatar
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1 vote
1 answer
128 views

433MHz RFM69 radio joystick controller for drone in Minnesota

I live in Minnesota. I have an Adafruit RFM69 433MHz transmitter and receiver. I'm building a quadcopter drone and wondering if I'm allowed as a hobbyist to send continuous data to my drone (such as ...
Alex Fish's user avatar
3 votes
5 answers
1k views

Handling simultaneous messages in wireless communication

I have a generic question regarding wireless communication and what techniques can be used to detect if two transmitters send the message at the exact same time. Since this is generic question and ...
Stazh's user avatar
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2 votes
2 answers
525 views

Decoding a 433 MHz energy monitor

I am attempting to capture transmissions from my own energy monitor, a Watts Clever EW4009 for use with Home Assistant. I believe it is an FSK signal, with 250 um packets. I have captured several ...
Denis S's user avatar
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1 vote
2 answers
17k views

Duplicating a 433 MHz remote control that uses "rolling code"

I'm having a 433.92 MHz standard remote control which uses "rolling code" encoding. Are other "rolling code" encoding standard remote controls interoperable, or do I need a more ...
croraf's user avatar
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2 votes
3 answers
249 views

Taiwanese Regulations of 433 MHz

I'm designing a wireless commercial device to be sold in Taiwan. I'm looking for transceiver modules, some of them work at 433MHz. However, I'm not clear if the 433 MHz is regulated in Taiwan. Does ...
Leonardo Márquez's user avatar
2 votes
1 answer
162 views

Recent reference for "why not to build RF circuits on breadboard"

I've noticed the occasional I've built my FM modulator/RF mixer/433 MHz oscillator according to plans from The Internet on a breadboard, now it doesn't work. We can usually refer the author to ...
mmmm's user avatar
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What dimensions would L1 in this 433MHz tank circuit receiver be if it is actually 1.5 turns?

Specifically, this circuit from Elektor: The asterisk denotes that L1 in this 433MHz receiver circuit would be 1.5 turns. If that is accurate, what would the dimensions of the inductor air core be? ...
user1995565's user avatar
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2 answers
853 views

On which layers of 4 should the trace antenna be (433MHz)?

I have designed a simple PCB with the follow layers Top Layer, high speed traces (rest ground copper) Inner 1, Ground Copper area everywhere apart on the very left side where the trace antenna will ...
Kris's user avatar
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-1 votes
2 answers
927 views

which antennas is better for 433 Mhz 30dbi LoRa module [closed]

I am searching a antenna for LoRa module. my first priority is distance. which is more long range, it is better for me. There are 3, 433Mhz 3dBi antennas. Can you help me which is best and why? if you ...
mehmet's user avatar
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0 votes
2 answers
3k views

Are there generic generic repeaters for 433 MHz communication (such as for doorbells)?

I'm having a 433 MHz doorbell which is too far away from the receiver (too many walls in between). Sometimes it works but other times it doesn't. I thought that there could be a 433 MHz repeater (just ...
adamsfamily's user avatar
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0 answers
310 views

433 MHz Antenna Layout

I'm trying to build a remote control unit and want to 'remote' the antenna from the 433 MHz Tx unit. I'd appreciate some feedback before I order as my antenna/RF theory is sketchy and I want to know ...
Josh's user avatar
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0 votes
1 answer
303 views

On a PCB, can an antenna for 433MHz RF be "far" from the transceiver?

When I design PCBs I always try to keep antenna as close as possible to the transceiver. Now due to the design I need the transceiver schematic on the left side but the antenna on the right side of ...
Kris's user avatar
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1 vote
1 answer
472 views

Circumvent 433MHz antenna printed on PCB

I'm tinkering on a cheap chinaware alarm center which receives signals from its detectors on 433MHz. It is located inside a metal box which forms a faraday cage and apparently reduces the range too ...
svoop's user avatar
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0 votes
2 answers
278 views

Can a similar crystal and not exactly the one on the datasheet be used on RF 433 receiver?

The datasheet of SYN531R suggests 13.51783 MHz crystal. I found available available 13.52127 MHz on an online store. It seems very similar to me, however in reality would it work and if yes, would it ...
Kris's user avatar
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0 votes
1 answer
949 views

Car Key Fob doesn't transmit RF, althougth everything else seems to be working

Before starting to describe the problem, I need to say that this is my first time posting on electronics.stackexchange. I don't have a deep knowledge of electronics but I usually can diagnose a ...
asergio's user avatar
1 vote
1 answer
319 views

433 MHz Transceiver - understanding OOK demodulator parameter 'OokFixedThreshold'

I would appreciate some help to understand a parameter for this device https://www.semtech.com/products/wireless-rf/fsk-transceivers/sx1231h. I'm far from an expert at RF matters and this question has ...
Smarties's user avatar
0 votes
5 answers
10k views

Determining the transmit frequency of a key fob

How can I determine the frequency of this RF module (car keyfob?) It should be 433 or 315 MHz. I have a 50MHz digital oscilloscope. Is there a way?
Roman Simonyan's user avatar
2 votes
2 answers
2k views

Generic 433MHz receiver, how to derive output signal voltage

I have a 433MHz receiver modules (Model number MX-05V) The input voltage is listed as 5V but they don't list the output voltage. I have seen this used without level shifting in a project in ...
Jabermony's user avatar
0 votes
0 answers
173 views

5X5 button matrix with 433Mhz rf module or NRF module

I have interfaced 433Mhz rf module and custom 5x5 button matrix with arduino. Keeping Keypad matrix at transmitter side and an LED on the reciever side as long as i hold down the button the led should ...
Prateek Kumar's user avatar
1 vote
2 answers
3k views

433 MHz Antenna - Balanced Dipole + Balun?

I've got three 433MHz receivers (all the same type) and I would like to increase the range on them (by which I mean the physical distance that the receiver can detect the signal from the transmitter). ...
Chris's user avatar
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0 votes
2 answers
312 views

Communication within 5-10 meters: RS-485 or Wireless?

As a follow-up for my previous question, can anyone please recommend for my application (communication between two floors of a building) as whether to use RS-485 or any wireless technique (I am ...
Maneesh Verma's user avatar
0 votes
1 answer
2k views

433 MHz receiver consumes too much power

I bought one of this modules (link), with the SYN470 chip on it. In the datasheet it's mentioned that in continuous mode with 433 MHz the current consumption is 3.9 mA which is a lot in my case. But ...
ElectronSurf's user avatar
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-2 votes
1 answer
2k views

In RF433 Mhz module What is the Bandwidth and Data rate that used to transfer data?

many of document I have read it that tell me this module has 2MHz and Data rate equal to 10Kbps and using ASK modulation how did it transfer 10Kbps on 2MHz what my question is why did used a large BW ...
blacky's user avatar
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4 votes
1 answer
4k views

Is there any country where the 868 MHz or 915 MHz ISM band cannot be used?

The product I am working on (Electronic Shelf Label) uses the 915 MHz radio frequency band and is currently being deployed in Asia. I am gathering the list of countries that the 915 MHz frequency is ...
uuwen's user avatar
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0 votes
1 answer
819 views

Where to solder antennas on 433mhz receiver/send

I bought some 433mhz senders and receivers and some 433 mhz antennas. Unfortunately I don't know where to solder the antennas. Where do I solder the antennas to and do I need special solder wire? ...
clentfort's user avatar
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0 votes
2 answers
2k views

HC12 Serial RF Transceiver with PIC16F886 Microcontroller

I'm trying to do a wireless communication between two PIC microcontrollers (PIC16F886) using the TX/RX lines using HC-12 RF transceiver modules (datasheet link below). https://statics3.seeedstudio.com/...
Vinay Sathyanarayana's user avatar
0 votes
1 answer
131 views

CI HT12E enable control to reduce power consumption

So, following this datasheet (check out Application Circuit 4), I managed to transmit a signal and receive it on the other end. The thing now is: the whole circuit is drawing 2 mA, and that is because ...
Pastre's user avatar
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0 votes
0 answers
284 views

Unable to intercept the code of my remote control at 433 MHz with RaspberryPi

I'm trying to reproduce the code generated by my universal 4-channel radio control with ...
jay's user avatar
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1 vote
3 answers
4k views

2.4GHz WiFi module causing interference on 433MHz RF receiver module

I have a prototype board which has two RF modules on it, a 2.4GHz Wifi module (ESP-01) and a low cost 433.92MHz RF receiver module (Wenshing RWS-371F-6). My 433MHz transmitter (a remote control) sends ...
abomin3v3l's user avatar
0 votes
1 answer
729 views

How does this 433Mhz garage remote control work without an antenna?

I have a 433 Mhz garage remote control that works very well even from 30 to 50 meters and it has no antenna! How is it possible that it works so well without an antenna? Also, given the picture of ...
Basj's user avatar
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0 votes
2 answers
504 views

Does the 433 MHz transmitter/receiver, transmit the voltage?

The title, says it all... I would like to know if the 433 MHz transmitter/receiver (couldn't find a datasheet, here is all I found on it) transmits the voltage, ...
FireGreeks's user avatar
1 vote
3 answers
506 views

I2C noise from 433MHz transmitter

I have built a little thermostat based on BMP280 temperature sensor over I2C, ESP8266 Lolin v3 and STX882 433Mhz transmitter. I have not added additional pull-up resistors or decoupling capacitors. ...
Rojj's user avatar
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0 votes
1 answer
43 views

Antenna Gain Vs IP68 plastic enclossure

I would like to buy this IP68 plastic enclossure below for my electronic project: https://www.chinaenclosure.com/products/102-70-52mm-ip68-waterproof-plastic-enclosures-for-electronics-from-china-...
Mehdi's user avatar
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