  We have fabricated a single Cooper-pair box (SCB) in close proximity to a
single electron transistor (SET) operated in the radio-frequency mode (RF-SET)
with an inductor and capacitor lithographed directly on chip. The RF-SET was
used to measure the charge state of the SCB revealing a 2e periodic charge
quantization. We performed spectroscopy measurements to extract the charging
energy (EC) and the Josephson coupling energy (EJ). Control of the temporal
evolution of the quantum charge state was achieved by applying fast DC pulses
to the SCB gate. The dephasing and relaxation times were extracted from these
measurements
