The pulse shaping amplifier outputs short pulses with around 10 mV/keV:
.2 ms/50 mV per division
These pulses have a similar amplitude to audio from a microphone preamp, so they can be digitized by feeding them into a computer’s soundcard. If the computer has dedicated audio input, connect the circuit as the headset microphone using a TRRS plug. Generally, the sleeve is ground, and the ring next to it is the microphone signal.
(Electronics)
(Ionizing radiation)
Yesterday, we demonstrated detecting soft X-rays using a BPW-34 PIN photodiode, and a charge sensitive preamplifier. Unlike a conventional G-M tube, the photodiode can measure the energy/wavelength of X-ray photons, which is characteristic of the source. However, the raw output from the preamplifier is not very usable; It is very weak, noisy and the pulses have long tails:
10 keV X-ray. 1 mV/1 ms per division. (It’s hidden by an aggressive bandwith limit, but there is 2 mV RMS noise here.
(Electronics)
(Ionizing radiation)
PIN photodiodes are diodes with a thick undopped/intrinsic layer between the P and N-type regions. This layer is typically around .1 mm, creating a similarly thick depletion layer. When light shines into the depletion layer it liberates electron-hole pairs, which, if reverse biased drift into the dopped regions, allowing a small current to flow.
X-rays: An X-ray photon1 can also knock an electron free, but the excess energy causes it fly trough the semiconductor, knocking more electrons free:
(Electronics)
(Ionizing radiation)