For a second iteration of the 433 MHz transmission between Espressif ESP8266 modules, I switched to RF modules based on the SYN115 and SYN480R devices. Largely because these work much better with the 3.3v supply rail and signalling that the ESP8266 uses.
I have something working with a center loaded "whip", the design of which was found on the web, but I'm intrested in getting the maximum range from this that I can, so I'm considering a full sized 1/2 wave dipole.
it doesn't take more than a minute on the web to determine that the end-to-end length of the dipole needs to be 345.4 mm, meaning a couple of legs, each 172.7 mm long should do the trick.
OK so far, and I even know where I want to attach them:
shows the transmitter module, and the receiver has the exact same "contact" pattern. Very conveniently, Ant
and Gnd
are right next to each other, so this shouldn't be at all difficult.
Except Gnd also needs to have a separate wire running to the ESP8266 as part of the power supply and signalling to enable the OOK transmission.
So what is likely to happen if I have +3.3V, Data and Gnd wires coming out the middle of the dipole? What options do I have to prevent this being a problem, assuming it is one?
-- Edit --
To expand on this, it may help to describe exactly what I'm doing. I want to send a signal from a temperature sensor that's outside the house to a receiver inside the house. (*)
So the two "constraints" are (1) this has to be able to get through an exterior wall of the house, and (2) about all I have for mounting is the wall of the house itself. Which in turn means a ground plane is somewhat out of the question. Thus the desire for a 1/2 wave dipole, that'll mount perfectly on the side of the house if vertically aligned.
(*) Sure, I can easily buy an off the shelf unit, but that's not the point here. This is as much a learning experience for me as anything, thus the preference to build it myself, and learn as I do so.
Ant
connector on the PCB. I have considered a length of coax, but wasn't sure exactly which cable to get. I would not want to bet anything on the success of using a length of "random" coax, e.g. RG 58 or RG 6. On the other hand, buying a super cheap 433 MHz antenna for a few dollars on ebay, and then throwing away everything except the length of coax has a certain charm to it. \$\endgroup\$