I am using a 315Mhz Transmitter and Receiver RF link kit between two arduino. What happens if I wire the antennas of both RX and TX to both ends of a 1 meter long metal wire? Will using a conductor instead of air channel affect the communication positively or negatively if it affects at all? What if its a 1m shielded wire? Will that help in noise reduction?

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    \$\begingroup\$ You will probably destroy the receiver if you try that. \$\endgroup\$ – JRE Dec 18 '15 at 9:01
  • \$\begingroup\$ Probably nothing will break depending on the design of the receiver. I would have to see a schematic before I can conclude if it will destroy anything or not. But why would you want to do this ? Why not use a wire instead ? For a distance of 1 meter these links should just work with their antenna's attached. If it does not work you have a different problem, connecting by a wire will not solve that problem. \$\endgroup\$ – Bimpelrekkie Dec 18 '15 at 9:10
  • \$\begingroup\$ The two modules(transmitting and receiving) got a metallic strip in between as a part of the physical structure. I was just wondering if it can be used for improving the communication. Thank you guys for your comments. Thank you @Autistic for editing my question. \$\endgroup\$ – Vishnu Mohan G Dec 18 '15 at 11:12
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    \$\begingroup\$ What are you doing? If you need wireless transmission, what is the connecting wire for? And if you need a connecting wire, why even use wireless modules? I mean, you are talking about 1 meter here. \$\endgroup\$ – R Drast Dec 18 '15 at 11:18
  • \$\begingroup\$ Consider using coax and an atennuator. Look at your transmit power in the spec and for any details on range or saturation - if you can't find any, estimate your typical path loss and use a similar attenuator \$\endgroup\$ – johnnymopo Dec 18 '15 at 13:20

There is a lot to explain here, the question seems ill thought out, but I will try, and perhaps we can elaborate as you give more information.

If you are trying to design a transceiver where Rx and Tx share an antenna, then the approach you have outlined is not valid. You either need:

  • Half duplex operation, using an Rx/Tx antenna switch and a proper antenna e.g. monopole.
  • Full duplex operation, using a duplexer/diplexer with Rx and Tx using different frequencies and again, a proper antenna.

However, it is possible that you are talking about making a test rig where the "air channel" is replaced by a cable. If that is the case, then:

  • You can connect the two using a coaxial cable.
  • You must have a large antenuator to simulate the channel and protect the receiver.
  • The attenuator value will depend on the Tx power and Rx max input rating listed in the "absolute maximum" section of the datasheet.
  • A good starting point to avoid trouble is 50 or 60dB.
  • \$\begingroup\$ Thanks Mark, What I meant is to replace the air channel with a conductor. Yes, you answered it. Thank you. \$\endgroup\$ – Vishnu Mohan G Feb 1 '16 at 8:36
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    \$\begingroup\$ @VishnuMohan if you edit the question a little then I will be allowed to up vote it but I cannot right now because my vote is locked. Also then there would be a clearer Q&A on the site for other people with a similar question \$\endgroup\$ – Mark Ch Feb 1 '16 at 8:51

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