DIY Geiger Counter with Nokia 5110 (3310) LCD and PIC16F876A; new prototype!

Take note, current version of the project is different and can be purchased as a kit for DIY here.

It starts here, but now I tried to work with Nokia 5110 graphic LCD. The problem I met was there no ready library for my PIC compiler! It's mean that I was forced to write my own procedures to initialize the lcd, clear screen, write texts and etc. After searching the web I found some arduino examples from sparkfun  and lcd datasheet. With Arduino library it was very simple to run this display, but my project build with PIC16F876A and I started to transfer the principles to my mcu. This forum thread was helpful for understanding how to write main display procedures. The results are in the current video. This is diy geiger counter prototype. It use only PIC16F876A for controlling all dosimeter functions. I transferred almost all program functions from version with 16x2 lcd to this version of the board. The hardware include voltage reference IC for precision voltage measurements.

The prototype work started from this:

And comes to this:

1. PWM control high voltage, the output can be tuned with 2 keys from 300V to 600V.
2. Measurement period automatically changes, depend on radiation level. See on the video how it happen when level goes up and down. Long period is better for the background.
3. Fast response scale on the display will show immediately levels changes, even before the measurement period will end. It useful when prompt response is required. The bargraph scales up to 800 cpm.

4. As before  UART, Arduino, Geiger Bot communication

5. Calibration menu (not presented in the current video) allow to changed conversion factor, alert threshold, high voltage and save all settings.

This work still in progress. Because the signal captured from tube cathode there is some problem with sensitivity to static electricity (if you touch the tube it will cause false counting) I think I need to make some small circuit changes. But if enclosure is used its unnecessary.

follow for updates... 

Review of Playduino One PTH DIY Kit

I purchased this simple DIY kit from eBay ( Item number:180977979792) for 10 usd. The kit do not include MCU, but I already have several Atmega328 chips and decided to try it. I found some online description for this product here. It Arduino Duemilanove compatible PCB with all DIP components, really easy to solder. Not from the newest versions of Arduino, but still useful. After the solder work was done the kit look like:

The PCB comes without FTDI chip. External CP2102 TTL module required for communication with software on the computer. But first, Atmega328 should be pre-flashed with bootloader. Because my MCU was blank I used USBasp programmer to upload the bootloader to Atmega. The board has ISP connector with MOSI, MISO, SCK, RST, VCC, GND pins. Follow this link for "How to upload bootloader". Arduino software reported some SCK synchronization warning after programming, but seems everything was successful and  bootloader was installed correctly. I connected FTDI module and tested the default LED blinking sketch.

I would recommend this DIY kit because of low price, but it require soldering and some firmware workaround. The drawback is that you need external TTL module, MCU and AVR programmer, but if you already have all of them, then it maybe good solution for cheap Arduino board.

New Design Simple Radiation Detector DIY Kit

http://www.rhelectronics.net/store/radiation-detector-geiger-counter-diy-kit-second-edition.html

High voltage converter based on self-induction circuit, where square waves drives NPN transistor to produce high voltage spikes over 10mH inductor. After multiplication we can get 350V-450V anode voltage. As before the PCB include high impedance voltage divider for easy calibration.

The kit compatible with Arduino, i.e. it can be used for sending interrupts to MCU. Please download user manual for more technical details about the kit.

PCB allow installation of SBM-20, STS-5 or J305 Geiger tubes. Soldering process require moderate solder skills. 

The kit can be used as nuclear radiation detector or, if you connect it to Arduino, as a part of COSM monitoring station / dosimeter. We supply 2 simple arduino sketches for the beginners, you can modify it to your needs.

Enjoy!

New Geiger Counter with PIC16F876A Prototype worklog updates

I'm working on new Geiger Counter based on PIC16F876A. It has absolutely new design. All functions including high voltage generating are assigned on the processor now, its mean no additional IC's. No more 555 timers and no logic IC's. So lets say more about software:

1. Measurement time is auto adjusted, depend on radiation level. It guarantee better accuracy on low background levels and also fast response to high levels. Time countdown is also displayed on the LCD.
2. PWM controlled high voltage stage. User can calibrate high voltage from 300V to 500V in menu. The tube voltage is also displayed on the LCD in real time. The ADC use different Vref, not from supply rail.
3. UART, Arduino, Geiger Bot communication.
4. Calibration menu with Alert threshold, Conversion factor. Parameters may be saved to EEPROM.

This work is still in progress, please follow updates. When it will be finished I think I'll run it like a new kit.

Online Radiation Monitoring Feed with Cosm

For online monitoring of current radiation level I created COSM feed here:
https://cosm.com/feeds/122314

I will try to keep it online most of the day time. The hardware that used its my DIY Geiger Counter, Arduino UNO with Ethernet Shield and SBM-20 tube. I modified the example arduino sketch to feet my conditions. Please follow.

SPECT Bone Scan photo / video radiation levels report.

Radiation Levels at SPECT Bone Scan.

My small photo/video report about Bone SPECT Scan I did today. The examination was done in  Hadassah Ein Karem Hospital (Jerusalem). I was injected with radioactive isotope of Technetium-99m and after 3 hours my body was scanned with Gamma Camera. I have my DIY Geiger Counter in my bag and I did some radiation levels logs. Right after the injection my body produced about 20K-25K CPM (100uSv/h average) at 1 feet distance! The radiation level goes down after several hours, but even after 7 hours is stay hot.

You can find more technical info about Geiger Counter Hardware and Logger Software at:
http://www.rhelectronics.net/store/diy-geiger-counter-kit.html 

10 minutes after the injection. 

1 hour after the injection. Radiation level depend on the distance from my body. At 10 meters I registered about 90 CPM and at 30cm (1 feet) is very high (17K-20K CPM!) I drank a lot of water to allow the isotope to spread over the body. I mute the buzzer sound because the dosimeter "goes crazy" and may disturb the hospital workers and visitors.  

After several hours the scan was done all my dosimeters at home still detect high levels at 1 meter from me. I will attach logs files. You can open it to see the graphs with "Radiation Logger" Software or with any csv files editor. I used my phone to create this videos that's why it has low resolution quality.

The graph log screenshot: You can see the difference in CPM readings depend on the distance I marked. Download logs files

And some Hadassah Radiology Hospital photos:

Update 18/03/13:

30 hours  from the injection of the Technetium-99m and my body is still produce gamma radiation. Log file attached. During the day I felt weak and mild nausea.

Regards the Wikipedia all total radiation dose I received is about 10mSv (30mCi or 1000mrem or 500 chest X-Ray). Its probably may affect my blood count but to check this its necessary to do a blood test.

P.S. 

I asked the technicians who did the scan if the radiation dose from this medicine examination is high or low and they said it's not significant total dose, but it seem not to be like that (regards the CPM readings I got)! Its not seems to be low level also because all radiation detectors around goes crazy from 5 meters distance. Probably the technicians were instructed not to cause panic among patients. 

פרויקט חדש "מונה גייגר שלי"

פרויקט חדש וחינמי לדוברי עברית - "מונה גייגר שלי"

כולל הסברים, מעגל מודפס ותוכנה

www.mygeiger.org