Solid State Radiation Detector with LCD Complete!

I added a PIC and LCD to my basic radiation detector and can now display total counts over time(up to 24 hours) or Counts/Sec and relative gamma strike energy level. The energy level varies as every gamma strike does not dislodge the maximum possible number of charge carriers. I take the maximum value registered every second and display. On average various materials indicate different levels, providing a crude detection signature. Besides the LCD display, this circuit has a sample and hold circuit which  is connected to  the PIC ADC module and also tied a another PIC I/O pin which switches from tristate to pulled low to reset the sample/hold circuit. The maximum sample rate is 13500 samples/per sec.


Link to Schematic:

Link to Video Demo:

Link to Code and pcb files:


23 thoughts on “Solid State Radiation Detector with LCD Complete!

    • I have code I developed using MikroC. I can post it but I don’t think I commented it very well , etc..let me look it over, and clean it up and I will try and post it in the next couple days.

      • Hi, Ray!
        Can You send me the source code?
        How the circuit works at low activity gamma environment /near background level/?
        In Your oppinion: can i use the CHARGE TIME
        or may be dsPIC required for more simple front-end?
        Thanks, with regards:

      • I will put a link to the source code(in the the next day or so). However this code is not well commented and hastily written so it may be a little difficult to get much from it. It was written with MikroC.

        With regard to background radiation…. The device can detect about a 50 KeV gamma ray or larger. It doesn’t matter what the source. Some background radiation is very high energy some is low. The background radiation generates a low number of strikes but usually high enough energy to be detected.

        Not clear on what you are trying to simplify? The PIC I am using is way overkill for the application. I am using it to do an ADC sample, then clear the sample and hold circuit and then simply drive an LCD. The ADC resolution is more than sufficient so not sure what a CTMU does for you or a more advanced micro.

        If your intention is to somehow make more precise measurements, I think you will see little benefit

      • I try to make a PIN dtetctor circuit nowadays.
        In my opinion the ctmu measures the PIN’s virtual capacity change due to charge change.
        It’s only an idea, i never use the CTMU yet. I just started to read about ctmu, and thought: its very interesting, but i have’nt enough time.
        “Links to the code”????

  1. Great post. I was checking continuously this weblog and I am
    inspired! Very ueeful information particularly the lastt part 🙂 I
    take care of such information a lot. I used to be seeking this certain info for a long
    time. Thanks and good luck.

  2. I sent you the files – you don’t respond to my emails – they show they are sent? No one else has any trouble – I do this all the time- I don’t know what to say?

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s