====== Receiver Circuits ======
To use the microphone as an input, you need to adjust the incoming signal level to the sensitivity of the microphone and put a capacitor in series to block the DC component introduced by most microphone inputs. The capacitor C2 is usually not needed, it is intended to remove noice.

{{:upm_scheme.png| Reception Circuit}}

Here are some examples of receiver circuits:

[[modupm|{{:pci_card.png|}}]][[modupm|Using the UPM thermometer as RF receiver for the 433.92MHz band]]

[[walterreceiver|{{:pci_card.png|}}]][[walterreceiver|An RF receiver for the 433.92MHz band by Walter Krämbring]]

[[walterduo|{{:pci_card.png|}}]][[walterduo|A generic high power 433.92MHz transceiver using an Auriel devices by Walter Krämbring]]