• 10 dec 2017: forum version update. In case of issues use this topic.
  • 30 nov 2017: pilight moved servers. In case of issues use this topic.
Hello There, Guest! Login Register

433 Receiver shielding
It is a difficult issue. The main problem is that most 433 MHz devices us OOK (On-Off-Keying), it is not a mudulated RF carrier but the RF carrier is turned ON/OFF, this creates a wide spectrum of frequencies, and virtually any filter approach te regenerate the original information will fail.

(06-18-2016, 03:46 PM)satsatt Wrote: My goal was to shield the "approved" receiver from any noise by putting it in an faraday cage ( alufoil box ) together with an TS-33C temp/hum sensor to record raw data because i would like to have this protocol implemented in pilight.
In principle a valid approach, but in particular any copper cable penetrating the alu foil needs to be shielded

(06-18-2016, 03:46 PM)satsatt Wrote: I was not succesful - the USB and data cable picked enough 433 signals from outside the Alubox to make this a failure.
You do need to run the cable trough a ferrite-core coild to block the hgih frequencies.

(06-18-2016, 03:46 PM)satsatt Wrote: It got even worse when i put the Pi with an powerbank also inside that box and let only the LAN CAT6 cable run out. Grounding the Alushield made no difference and even a 433remote control signal from outside could be recognised correctly inside the box ( so not all false noise )
You do need to add blocking condensators to the power line (tantaluum for each board, ceramic for each chip)
(06-18-2016, 03:46 PM)satsatt Wrote: so what are my conclusions

1 the receiver IS sensitive even without an antenna connected
2 the receiver near the pi is not a good idea because of much noise of the pi
3 a LAN cable can cause the shielding to be penetrated by 433MHz signals
One of the main problems is that access to the AGC logic of the receiver is typically not possible.

(06-18-2016, 03:46 PM)satsatt Wrote: has anybody a concept of a shielded connection between receiver and the pi?
One power supply
One common ground for the analog part
Another one for the digital part.
All power cable in star configuration and tantaluum/deramic condensators added.
Digital and analog components separated as far as possible

Messages In This Thread
433 Receiver shielding - by satsatt - 06-18-2016, 03:46 PM
RE: 433 Receiver shielding - by wo_rasp - 06-21-2016, 09:10 PM
RE: 433 Receiver shielding - by HazelMiki - 07-13-2016, 07:12 PM

Possibly Related Threads...
Thread Author Replies Views Last Post
  ESP8266 with 433 MhZ Transceiver/Receiver as Remote for Raspberry Tueftler1983 2 1,939 05-12-2019, 06:31 PM
Last Post: bitboy
  Approved Sender and Receiver Kit curlymo 72 69,129 04-07-2018, 03:25 PM
Last Post: dick
  Filter kit in 315 receiver? ceandre 1 1,405 04-14-2017, 10:10 PM
Last Post: wo_rasp
  Low Pass Filter and Receiver in Series? re-post Gustavo Woltmann 1 1,582 03-08-2017, 05:25 PM
Last Post: pilino1234
  Looking for 868mhz receiver curlymo 24 20,672 12-07-2016, 02:51 PM
Last Post: rorie
  Low Pass Filter and Receiver in Series? Hauke 3 2,976 08-30-2016, 08:25 AM
Last Post: wo_rasp
  433mhz receiver for window shutters stratege-0815 0 1,645 02-18-2016, 12:14 PM
Last Post: stratege-0815
  433mhz USB Sender/Receiver raws99 8 9,410 11-17-2015, 11:29 PM
Last Post: curlymo
  433 Mhz receiver mike 9 5,892 09-30-2015, 04:01 PM
Last Post: lxz
  sender and receiver 433,42 stefanzweig1979 6 5,563 09-14-2015, 10:05 PM
Last Post: wo_rasp

Forum Jump:

Browsing: 1 Guest(s)