[hvalentim]

I am testing the Superheterodyne 3400 RF Link kit (TX/RX couple) I received in a test board.

I am using a couple of Nanos powered by the PC USB ports and the Virtualwire receiver/sender demo examples (transmitter in PIN D12, receiver in PIN D11), which loop transmit a “hello”.

It is working. The TX part, even using an improvised non-optimal league of 18 cm fence wire as antenna, seems to be "heard" by a Wouxung portable radio at least 200 meters away, with a house and a few trees in between.

As for the RX part, it is receiving better without the improvised antenna than with it, so I am certainly missing something. I suspect this may be the way I am connecting the GND.

It turns out the RX unit has no less than 3 pins labelled “GND”, two of them side by side, next to the ANT (antenna) PIN. So I am figuring two hypothesis:

H.1 - perhaps I should connect the GND closer to the ANT pin to the central pin on an SMA PCB connector and the other (the one farther away, next to the 5V pin) to the Nano GND? (currently I have both of them in common with the Nano GND)?

H.2 - perhaps I should connect the GND closer to the ANT pin to the second GND Nano Pin, the one in the opposing row, where D11 is located?

Can anyone please help me enlighten this?I found plenty of examples on how to wire 433Mhz receivers for test purposes to an Arduino, but not this particular receiver model.

Also, does anyone know about a piece of software library/a procedure (preferably using the Nano itself and not involving additional hardware) allowing me to have an idea of the quality of the received signal? So I can subsequently test different antenna models.

Thanks a lot,
HDV