Third version prototype V3

A project log for Gamma PIN - Semiconductor Radiation Detector

An attempt to design and deliver universal and accessible radiaton analyser to be used in nuclear spectroscopy

Marcin WachowiakMarcin Wachowiak 02/16/2020 at 15:092 Comments

Recently I have finished and produced the third version of the detector. Several improvements have been made considering the issues with the previous versions. All files including gerbers, schematics, boards and latest simulation can be found on my GitHub repository. Change log:

Preamplifier board
Preamplifier top
Preamplifier bottom
Signal processing board
Signal processing top
Signal processing bottom


A. M. Aitken wrote 02/19/2020 at 17:33 point

You've also moved from the discontinued BF862 to the CPH3910.  I'm interested to know how well they compare.

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Marcin Wachowiak wrote 02/23/2020 at 17:32 point

It is hard to tell whether there are any significant differences. I couldn't observe it with measurements of the assembled detector as there is no clear reference or calibrated source. So, I performed a simulation with both CPH3910 and BF862. Only the transistors were replaced, the rest of the circuit remained unchanged. There is no noticeable difference in the results. Perhaps in noise figures. Nevertheless, both transistors perform quite well and CPH3910 seems to be a reliable equivalent of BF862. Some differences may occur over a wider spectrum of energies - (currents) maybe then the results would vary more.

Here are the screens from the simulations showing the plots. CPH is on the left and BF on the right:

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