Beta version of extended MCA ver.3 with Isotope Identify
That project grow and bring me new challenge. It started with the basic MCA module ver.1.00 and ver. 2.00 that I will continue to support and update software for all existing hardware. However I always wanted a little more than a detector or gamma grapher display. Even when a distance between a professional system and an amateur DIY device looks a huge chasm, I still want to get closer as possible to the functionality it possible to get in DIY field.
What was the challenge and what makes it different:
1. 8-bit PIC-18 processor... Yes I know all modern embedded projects uses 32-bit or 24-bit processors because of floating point, speed, RAM size and etc...But I personally love 8-bit and I think PIC-18 series are great. The project done as it done and works nicely. However I used all possible resources of the PIC-18 chip and mikroe compiler. Next revisions probably will have different generation of CPU.
2. SAR ADC 10 bit. It found as working same or even better than a cheap audio cards that folks uses for amateur gamma spectroscopy on computer. My MCA has same speed limitation as an audio card based device - recommended up to 500CPS
3. ver.3 got internally memory to store spectrum data mostly because I requested faster data dump and ability to load previously saved spectrum to display. ver.1 and ver.2 still utilize SD card, but their data dump works very slowly at the moment you want to save spectrum file. Pros and cons here. SD card allows you to get ready files, but slow. Memory storage works very fast, but require PC application to download and format the data.
4. ver.3 got USB terminal. For data transfer and some complicated calibration or debug process.
5. All editions (1,2,3) are supporting scintillation mode for searching with scintillation probe. All editions are supporting output for audio sounder since 1.03a firmware.
6. ver.2 and ver.3 can come with integrated High Voltage power supply and signal amplifier, that makes it easy to get a portable device on one PCB.
7. ver.2 can run on 2xAA batteries. ver.3 got lithium battery charger as it has already integrated USB port.
8. Isotope identification function for Am-241, Cs-137, Co-60. Still in beta only for ver.3 and I don't know if it will be possible to add identification for ver.1 and ver.2 boards firmware because of memory limitation due to SD fat size.
9. In prospect, I want to implement temperature correction for the ver.3 However it's not an easy task, same as 8:), since light output of crystal is non linear.
Here is the video of the beta ver.3 as it exist today:
If you live in Israel and want to participate in the project then write me an email and tell about you!