Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

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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433MHz quarter-wave length antenna: longer is better?

I am trying to conduct an RF project using XY-MK-5V / XY-FS modules: link here My problem is that even though most blogs and Google searches for these modules use a quarter-wave length antenna (roughly 17.2cm), my transmission is worse than when I…
parakmiakos
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Why is 433 MHz used widely in RF modules?

I was planning to interface an RF module to my PIC16F877A microcontroller and was exploring the web. I came across many modules which use 433 MHz as the standard frequency. Why is it so? Can't we change the frequency as per our requirements?
santhosh
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Wireless Home Automation 2.4GHz versus 433MHz

Project specifications - This is an **Arduino** project - This is supposed to be internationally applicable I am working on a home automation project which might go into smaller production. The project is wireless and the connections would be…
Roberto Anić Banić
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Why is 433 MHz still used?

The new RF frequencies are 868 MHz for Europe and 915 MHz for the US. I heard 433 MHz is barely regulated, read: it's chaos. Then why are 433 MHz RF modules still used? Are they cheaper to produce?
Johan.A
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Boost 433 MHz receiver module receiving signal (XY-MK-5V)

I am using some "no-name" (in fact "XY-MK-5V" stands on the board) 433 MHz receiver (and transmitter) on an Arduino project. I can receive the signals sent from my other Arduino very good (it sends with 12 V as mentioned in another question). The…
Tobi
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Improve range of 433MHz RF link

I have a system comprised of a wireless sensor which transmits temperature readings to a main base. The wireless sensor system is made up of: 12F683 pic to take the temperature reading (manchester encoded) RF Solutions AM-RT4-433 transmitter to…
SimonBarker
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What will it take to build a DIY 2km (city conditions) RF transmitter (433Mhz)?

This is my first question on this site. I am not an electronics/electrical engineer so pardon my depth of knowledge. I am trying to build an RF transmitter/receiver. These are my end goals : a text (bytes) transmission. (Voice not required) 1.5 -…
Vik
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433 MHz module antenna ground

I have these common eBay 433 MHz module pairs pictured below and am trying to hook up an external antenna. On the TX there is a little hole marked ANT which works for that. On the RX pictured (XD-RF-5V), there is a similar hole with no markings that…
Hayden Thring
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Design rf trace antenna 433MHz + 315MHz on pcb

I'm a hobbyist and I'm designing a PCB in Eagle that include micro controller and RF receiver and transmitter, 2 modules of 433mhz and 2 of 315mhz, I have a defined place on the PCB of 10x50 mm for the 433mhz antenna, and another 10x50mm for the…
itai
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Using 433 MHz Tx/Rx without encoders/decoders

I want to use Tx & Rx Modules of 433 MHz standard modules you find everywhere. I just want Tx module powered up and Rx module should respond (probably key press) on Tx module. I don't have any encoded data to send (by using HT12D, HT12E…
Heena Shah
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Microphonic SAW transmitter?

I built this very simple SAW transmitter, with a simple "spring" antenna for the right frequency. To test it, I tuned a portable receiver to around 433.92Mhz and fine tuned it until I heard silence. But I noticed that when tapped the board, the…
hjf
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Datasheet/screw function on XY-MK-5V 433 MHz receiver?

I cannot find a datasheet for my 433 MHz receiver (which seems to be a XY-MK-5V), which looks like this: Also, I was wondering what is the use of the screw (on top of the green box with copper wire circled inside)... just to open the green box or…
Michel Keijzers
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433 MHz receiver

I'd like to build a 433 MHz receiver from scratch. Is there a schematic or some material to learn how to build one? Google search didn't come up with much in the way of building one from scratch.
Joe
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433 MHz VS. Manhole Cover

I'm working on a sensor which purpose is to measure the water level of a sinkhole without getting in touch with the wastewater. The Sensor is mounted beneath the manhole cover --> The underside is formed like a rhomb and the sensor fits perfectly in…
Peter S
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Attiny85 hardware interrupt unreliable, 433 MHz remote

SCROLL DOWN TO SEE THE SOLUTION (UPDATE II) ORIGINAL POST: I am currently building a 433MHz remote with two buttons. The remote is controlled by an Attiny85v(8MHz). Sadly it does not work very reliable, sometimes it works other times nothing…
cgross
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