Methods for operating a portable electronic device to conduct mobile payment transactions are provided. The electronic device may include near field communications circuitry having a transmitter, a receiver, and a field detector for detecting a field from a merchant terminal. The receiver is typically idle. The receiver may be activated when the field detector detects that the electronic device is within the field of the merchant terminal. The transmitter may then be used to perform link establishment and data transfer. If the payment transaction fails for any reason, one or more hardware settings on the electronic device may be adjusted to help increase the chance of a successful transaction in a subsequent payment attempt. Another transaction may be attempted when the user moves the device out of the field and back into the field or may be performed automatically as long as the device is still within the field.