Problem Sending Signals

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Hi,

i use a couple AB440s socket switches to control lights, and sometimes i have a problem that they won’t switch.

I think it’s something with my cabling or soldering, because when i touch the antenna it works sometimes.
Don’t get me wrong the switching works 70% of the time but then it just fails, no debug output, all good but the socket switch doesnt do anything.

I bought this antenna:

http://www.amazon.de/gp/product/B00JG4XNBY?psc=1&redirect=true&ref_=oh_aui_detailpage_o03_s00

I cut off the connector and soldered the “inner” contact to my 433mhz sender, i just removed the shielding.
So my questin is: did I do anyting wrong here?

I use the pimatic homeduino setup and use this sender/receiver kit i believe:

www.ebay.nl/itm/433MHz-Superheterodyne-3400-RF-Transmitter-and-Receiver-link-kit-/251131859045?pt=LH_DefaultDomain_0&hash=item3a78a01065

On the Receiver i just have a piece of cable and can receive everything in the whole house and garden with no problems.

thank you for your help!!

would it be better to solder the shielding to the gnd connector on the sender?

You say you have a couple of switches. Do you sometimes simultaneously switch them, or really short after another?
433 is a “sloppy” protocol. It also sends a lot of garbage thereby overflowing other signals. If these 30% misses occur during fast switching between several switches (and other 433 equipment?), then simply try with longer interrupts between the switching.

no, it also happens if i just switch one thing, for example i turn one light off in the evening

but when 1 device doesnt work, all others work without any problem…and its not always the same device

@theslashy said:

would it be better to solder the shielding to the gnd connector on the sender?

Well, I think it should be connected to “earth ground” or “chassis ground”. For a try you can connect the shield to the ground of the sender, but this may make it even worse. Did you try to use a simple wire instead of the antenna like you do for the receiver?

See also http://www.nemcon.nl/blog2/2015/07/aa for some tipps on denoising the receiver and transmitter using three capacitors.

I had connected a simple wire before but the reception was quite bad and had the same problems.

My Pi is in the chassis of a old mac mini, maybe I’ll connect the shielding to the chassis of it…

what bothers me is that two of three switches work perfect but one not, and then i touch the antenna or put my hand around it and then it works after a few tries

@theslashy said:

I had connected a simple wire before but the reception was quite bad and had the same problems.

That’s confusing as you wrote earlier: “On the Receiver i just have a piece of cable and can receive everything in the whole house and garden with no problems.”. Did you mean “transmission” rather than “reception”?

@theslashy said:

what bothers me is that two of three switches work perfect but one not, and then i touch the antenna or put my hand around it and then it works after a few tries

May be you can do some more tests with the two switches which appear to work perfect as you say. What is the maximum range, i.e. maximum distance between sender and switch which is still working reliably?

May be the third switch is an “outlier” or has some defect?!

@mwittig
Yeah sorry:
so i have a simple wire on the receiver wich works perfect

and i had also a simple wire on the transmitter which had the same problems as the “real” antenna and also not enough range.
So i soldered on the Antenna, got better range but the same problems.

And it’s not always the same switch that makes problems, sometimes it’s this one sometimes the other one.

I just soldered the shielding to a cable and connected it to a gnd pin on the arduino, for now everything works perfect, i will keep an eye on it, perhaps this is the problem.