The ALPHA RF Transceiver Module 433MHz

///The ALPHA RF Transceiver Module 433MHz

The ALPHA RF Transceiver Module 433MHz

The ALPHA RF Transceiver Module 433MHz

Picture of ALPHA RF Transceiver Module 433MHz SMT next to 20 pence
ALPHA RF Transceiver Module 433MHz SMT


These were found whilst looking into potential ways of implementing wireless communications. They don’t offer the most straight forward way of communicating between the micro-controllers for the system but have an impressive amount of functionality for their price.

These were purchased from RS at £3.90 per unit. (


Transmit range up to 300m
Data Rate up to 115Kbps
Programmable output power
Operating Voltage 2.2 to 5.4V (TX & RX), and 2.2 to 3.8V (TRX)
Standby current <300nA
Programmable frequency deviation
SPI interface for configuration
Clock and Reset Signal for External MCU
Wakeup timer
Automatic antenna tuning
Differential antenna output
Low-battery detection
EMC Compliant , FCC Compliant
Operates from -45 to +85°C


+ Physical Unit

Potential Problem: Due to the 2mm pitch it is not possible to solder pins which will fit straight onto a breadboard for prototyping. A PCB the units can be soldered to with standard sizes will have to be created.

Dimensions for ALPHA RF module
Dimensions for ALPHA RF module (From Data sheet)

+ Pinout

Pin-out for ALPHA RF module
Pin-out for ALPHA RF module (From Data Sheet)

Pins of interest:

PIN Definition Function
1 SDO Serial Data Out Pin
2 nIRQ Interrupts request output?active low?
7,10 GND Power ground
8 ANT Antenna Connection
9 VDD Positive power supply
12 SDI SPI data input
13 SCK SPI clock input
14 nSEL Chip select (active low)

+ The SPI Interface

It seems everything can be done via the SPI interface. All parameters are set to default on power on and only retained whilst the unit is in sleep mode. This means some kind of initialization routine will be required.

+ SPI Tech Details:

  • Data bits on pin SDI are shifted into the device upon the rising edge of the clock
  • Data is only shifted in when pin nSEL (slave select) is LOW
  • All data are sent MSB first

+ nIRQ Interrupt Request

IRQ generated on the following events (nIRQ pin pulled low):

  • The TX register is ready to receive the next byte (RGIT)
  • The RX FIFO has received the pre-programmed amount of bits (FFIT)
  • Power-on reset (POR)
  • RX FIFO overflow (FFOV) / TX register under run (RGUR)
  • Wake-up timer timeout (WKUP)
  • Negative pulse on the interrupt input pin nINT (EXT)
  • Supply voltage below the pre-programmed value is detected (LBD)


Data Sheet with more info >

They seem much like these units  >

By |2016-11-05T11:17:48+00:00November 3rd, 2010|Lightive Project|0 Comments

About the Author:

A PhD in Electronic Engineering. A love for photography ( An interest in tinkering, electronics and design. (

Leave A Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.