Patent ID: 7573572

Claim:
A drift tube amplifier, the drift to be amplifier having an input and an output, the drift tube amplifier comprising: a current-to-voltage converter for converting extremely low input current to a voltage; a first order band pass filter for reducing unwanted noise within the voltage, the first order band pass filter electronically communicating with the current-to voltage converter; an inverting second order loss pass filter electronically communicating with the first order band pass filter; a non-inverting second order low pass filter electronically communicating with the first order band pass filter; a polarity switch, wherein negative voltage passing from the first order band pass filter enters the inverting second order low pass filter, and positive voltage passing from the first order band pass filter enters the non-inverting second order low pass filter such that both negative voltage and positive voltage is passed as positive voltage to the polarity switch, the polarity switch electronically communicating with the inverting second order low pass filter and the non-inverting second order low pass filter; a voltage controlled amplifier for adjusting the output voltage level of voltage from the polarity switch, the voltage controlled amplified electronically communicating with the polarity switch; a logarithmic ratio converter for converting the voltage from linear to LOG scale, thereby increasing the dynamic range of the output, the logarithmic ratio converter includes a log ratio amplifier for computing the log ratio of an input current relative to a reference current, a scaling amplifier for shifting and scaling the output level to a desired range and a second order low pass filter, whereby the voltage passes through each of these, the logarithmic ratio converter electronically communicating with the voltage controlled amplifier; an output buffer, the output buffer passing the LOG scale voltage to a processor board, the output buffer electronically communicating with the logarithmic ratio converter; and, a gain-control for remotely adjusting the output voltage level.