RF 433 remote control

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auto_mitch

Joined: 14 Oct 2004
Posts: 212
Helped: 20

28 Aug 2007 14:49 rf remote control schematic

I am trying to build a rf remote control. I have construct the following schematics but it doesnt work. The encoder and decoder ICs are from Holtek (HT12E & HT12D) and the rf receiver,transmitter are from telecontrolli (RR3-XXX & RT4-XXX). Can u help me? i have check everything but i dont know what is going wrong.

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electronicus

Joined: 19 Aug 2005
Posts: 188
Helped: 16
Location: Romania

28 Aug 2007 16:23 rf433

The schematic is not corect. Here your are the corect Rx-Tx design.

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auto_mitch

Joined: 14 Oct 2004
Posts: 212
Helped: 20

28 Aug 2007 16:43 rf 433

You think that the diodes is the problem? In the following application the encoder schematic includes these diodes.
http://www.circuitcellar.com/library/print/0102/millier/millier138.pdf

electronicus

Joined: 19 Aug 2005
Posts: 188
Helped: 16
Location: Romania

29 Aug 2007 14:37 remote 433

An other RX-TX project.

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rogerynt

Joined: 06 Mar 2007
Posts: 109
Helped: 11

01 Sep 2007 11:48 433 remote control

What Transmitter do you use ? Are you sure it works at 12V ?

Rogerynt

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electronicus

Joined: 19 Aug 2005
Posts: 188
Helped: 16
Location: Romania

01 Sep 2007 16:20 saw 433

The maxim voltage for RT-4 TX Module is 14v.

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rogerynt

Joined: 06 Mar 2007
Posts: 109
Helped: 11

05 Sep 2007 7:12 rs232 rf433

Please capture the data.

1.) Connect probe1 to Tx data of transmitter

2.) Connect probe2 to receive data at Rx

3.) Use probe1 at trigger and make they are common gnd

4.) Capture both Tx and Rx data on scope

The possible reason is as following :

Rx switched on before receiving data so that it picked up both noise and signal. After demodulation, there were random pulses ( background random noise being amplified ) appeared before valid data arrived. As the decoder could not distinguish whether these ramdom pulses were part of the code or not. The decoder will decode whatever it received therefore it treated the random pulses as part the the code and hence wrong output.

Rogerynt

halee awan

Joined: 08 Apr 2006
Posts: 101

03 Jan 2008 9:14 am-rt4-433

hi auto mitch
i have also made the same project
i am using 892051
that give the serial data to TX (RTF3 okwelectronics)
and on the Receiver end i reciev data from RX (RRF1 okwelectronics) and direct it to 892051 that direct it to pc rs 232 after some manipulation ............
i monitor the rx data on the hyp terminal but
auto mitch i dont know what is going wrong that the receiver doesnt receive any data packet ,after some time i saw on hyp terminal raw data, not exact packet that was transmiited by the TX
auto mitch i want to get help about this if u have captured