433 Mhz receiver: How to get a better reception?

---

@darkside40 Regarding the separate power supply for the receiver @lschip isn’t sure how to wire it up and I am not 100% sure either. Is it OK, to simply connect the power supply (assuming it provides regulated 5V) directly to the receiver pins or is a different wiring required?

@mwittig The datasheet (http://www.jmrth.com/en/images/proimages/RXB6_en_v3.pdf) of the RXB6 says that it can work from 3,0-5,5V so directly attaching it to the 5V of an USB Power supply should be no problem.

I would add two capacitor between 5V and GND to this module, one small 100nF and one slightly bigger (Something between 100-470µF). To get rid of bigger ans smaller ripples on th supply line.

Unfortunately the datasheet does not tell which is the best supply Voltage for this Modules.
But what i can see on @lschip pictures it seems that not all GND pins are connected to GND?
Could be an issue?

I will do some test with this thing on the weekend, when i have some spare time and make use of my new el cheepo USB Osci.

No, not all GND pins are connected, should they?

I think of using the usb feed (5v) to the arduino (steeling from the arduino board) to feed the receiver, is this ok?

Take a measurement and see if it is closer to 5V than the 4.6V your had before.

Its a bit trial and error. I assume when the GND Pins are there they should be connectec. Cant make it worse i think… The thing i ask myself is why that module has two 5V inputs?

The module doesn’t have two 5 volt inputs. The arduino is fed by the Rapberry with a usb cable. I want to use this 5 volt (i didn’t messure this yet).

The arduino has a 5 volt out pin that isn’t 5 volt but 4,6 volt. This is what I have used.

Strange is that when I had the receiver on the gpio on the Raspberry (3,3 Volt), without any filters, the reception was much better…

can you try adding a ground between receiver and RPI? I had some trouble with range too, still dont know why but it was a problem with ground

you feed the arduino by the usb port of the raspberry?
maybe the raspberry can´t deliver enough current to the arduino… that could also be the reason for dropping to 4,6v…

Uuh, yes, I feed the arduino with the usb of the rapsberry. How else can I connect the arduino to the rapsberry?

@lschip said:

ith the usb of the rapsberry. How else can I connect the arduino to the rapsberry?

• via an active USB hub - This is the solution I have, as connecting the Arduino Nano directly to the Raspi did not work in my case. I have a Raspi A, however, and it may work for you depending on the Arduino and Raspi model you have
• if you don’t have an active USB hub and don’t want to spend ~15 EUR to get one you may also try an Y-USB cable which cost about 3 EUR.

Ah, but I use the raspberry pi 2, quad-core CPU, 1GB RAM.
I think that the USB power is very much approved with this model. Do I still need a USB hub then?

Reading all the reactions I see the following possible solutions:

• more power (amps) to the receiver: usb-hub, y-cable
• higher and more stable voltage: 5 volt, still not sure how to connect this
• making a ground from the receiver tot the rapsberry: some how
• adding capacitators filtering noice
• connect all the ground pins on the receiver
• shielding the receiver: dont know how to do that other that replacing the receiver
• going back to connect to the gpio pins of the raspberry (on 3,3 volt)

When I have time I’ll try some things…

@lschip yes, with raspi2 USB power has been improved, so forget about external power supply for your arduino. The other point is whether or not it make sense to provide external power to the receiver as the the voltage provided by Arduino is 4.6V. As you said the receiver worked fine for you when connected it to Raspi 3,3V I think the voltage / power supply is probably not an issue in your case. So, I think you should trial other suggested measures first like de-noising using capacitors, shielding, antenna tuning to start with. I am also investigating this at the moment and will let you know about my findings

Ok, I did a few tests:

I connected all the pins of the receiver (gnd’s and 5 v) but that didn’t change anything.
Then I replaced the antennas with my thick antenna wires for thinner ones: the reception was worse.
Then I cut of the antenna of the sender and now I have a much better reception!!!

Now I have a good reception but this is strange isn’t it?

Without a sender antenna I have reasonable good reich but I don’t like this “solution”…

Has anyone ideas for a better solution?

Here a image of my transmitter an receiver (now I cut off the senders antenna):

Hello all,
I was very frustated because I bought a weather station and sometimes the receiving was fine sometimes not but with the station it self everything was fine the hole time. So I started with testing of the best result antenna , receiver and so on. After 4 days hard work and not even my favorite result I opened the base station of the weather station, to have a look how they are doing it. So I saw a a RX60B receiver ( I guess that 's the 3400rf) and a antenna with little bit more than 35cm. I was surprised because everyone is writing you need 17.3cm. The next day I created a 35cm antenna with the RX60B (bought it from pilight) and …YEAH I’M HAPPY NOW…no disturbance or something else since then. 😃

@temp 17,2 is 1/4 wave length while 34,4 cm is 1/2 wave length. Generally, you can’t say longer is better, but some users have better range with a longer antenna. It should also be noted some receivers (and transmitters) already have an antenna coil on the PCB which in some cases cannot be bypassed. If it cannot be bypassed the antenna length should be a little-shorter. See also http://electronics.stackexchange.com/questions/132051/433mhz-quarter-wave-length-antenna-longer-is-better

@mwittig:Of course you are right with your explanation. I only wanted to show some other experienc because now where you can read about trying out a longer antenna. I’m pretty sure that a lot or people (even me) read it but doesn’t think about this possibility. So that was the reason that I wrote it down.

I have had it (thinking about giving up),

I build my receiver and transmitter again from scratch with new modules and still my receive range is poor.
Again when I cut off the senders antenna the receiver range is better (total distance 3-4 meters), Somehow they seem to interfere with eachother.

I use this receiver: http://www.ebay.com/itm/Geeetech-3400RF-433Mhz-Superheterodyne-Transmitter-and-Receiver-Module-Arduino-/221504167012?hash=item3392ad5c64.

I saw that there are also recevers with some shield: http://www.ebay.com/itm/Geeetech-433Mhz-Superheterodyne-3400RF-Transmitter-and-Receiver-link-kit-Arduino-/200974005470?hash=item2ecafbf4de

Is that the problem, that I don’t have that?

Has anyone pictures of your sender / receiver ?

Thanks in advance.

@lschip This is the one I have, it’s working fine with a small piece of wire as external antenna, but for niceness i’m thinking about buying this one:

http://www.tinytronics.nl/shop/433Mhz-Antenne?search=antenne

http://www.dx.com/p/geeetech-superheterodyne-3400-wirelesss-receiver-433mhz-rf-transmitter-kit-green-370793#.VfnGt_mqpBc

@lschip said:

I saw that there are also recevers with some shield

i am having several RXB6 / 3400RF receivers here but they all have shields.
i was always thinking that the picture without shield is only for demonstration purpose whats underneath the shield. yours is without shield?!

check the hardware tip again, there’s another receiver mentioned that should be ok too :
http://forum.pimatic.org/topic/487/hardware-tip-433-mhz-receiver-for-pimatic/3
maybe go for this one …

Ok, it will be my last try, I’ll go for a new receiver.
Now I saw this one: http://www.ebay.de/itm/Manchester-Super-heterodyne-ASK-OOK-RF-Wireless-Receiver-Module-433MHZ-112dBm-/280936648330?pt=LH_DefaultDomain_0&hash=item4169210e8a&autorefresh=true

It claims to have a sensitivity of -112db in stead of-105db of the 3400RF Superheterodyne. Is this a good option too or do I risk a disappointment again?

Thanks in advance.

well, don’t know about these, but you could give it a try and report us about your experiences.