BPW34 photodiode radiation detector

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • barry wilkins
    Senior Member
    • Aug 2009
    • 172

    #1

    BPW34 photodiode radiation detector

    I have trying again to make a radiation detector using a semiconductor diode.
    I tried last year but gave up on it.
    Downloaded a number of ideas from the internet ,but again not much luck getting the thing to work.
    One circuit used a fet but this amplifier this seemed to be biased wrong so it will not work.
    I used a circuit using an opamp this would not work either with the BPW 34 ,it worked with a decapitated BFY 55 transistor covered with a little piece of Al foil over it.
    The first circuit I used came from Elektor ,again this does not work properly ,when you shield the circuit to keep out the visible light it breaks in to oscillation.
    Im sure this is caused by the capacity changing in darkness .

    Has anybody tried these detector circuits?

    Barry Wilkins
  • stj
    Great Sage 齊天大聖
    • Dec 2009
    • 30991
    • Albion

    #2
    Re: BPW34 photodiode radiation detector

    it may help if you posted the chems.

    but is it really usefull other than knowing your fucked - i mean it's such a small surface area on your sensor that it cant be acurate.

    Comment

    • ben7
      Capaholic
      • Jan 2011
      • 4059
      • USA

      #3
      Re: BPW34 photodiode radiation detector

      Originally posted by barry wilkins
      I have trying again to make a radiation detector using a semiconductor diode.
      I tried last year but gave up on it.
      Downloaded a number of ideas from the internet ,but again not much luck getting the thing to work.
      One circuit used a fet but this amplifier this seemed to be biased wrong so it will not work.
      I used a circuit using an opamp this would not work either with the BPW 34 ,it worked with a decapitated BFY 55 transistor covered with a little piece of Al foil over it.
      The first circuit I used came from Elektor ,again this does not work properly ,when you shield the circuit to keep out the visible light it breaks in to oscillation.
      Im sure this is caused by the capacity changing in darkness .

      Has anybody tried these detector circuits?

      Barry Wilkins
      Not surprised, most circuits on the web are either only marginal, or have significant issues. Or, it worked fine for whoever designed it, but you have it built a little differently, and so it doesn't work right.
      Muh-soggy-knee

      Comment

      • barry wilkins
        Senior Member
        • Aug 2009
        • 172

        #4
        Re: BPW34 photodiode radiation detector


        Hi tried to attach a picture showing the circuit by B Kainka in Elektor.
        If you look at the layout the circuit is different ,some of the resistors are of a different value and it seems that the cathode of the diode is ac coupled to the amplifier.
        Thinking about it ,my BFY55 transistor is two diodes one forward biased and one reverse biased ( base to emitter) so perhaps that is making a difference.
        Also circuits I have seen do have a coupling capacitor to the amplifier .

        Barry Wilkins
        Attached Files

        Comment

        • budm
          Badcaps Legend
          • Feb 2010
          • 40746
          • USA

          #5
          Re: BPW34 photodiode radiation detector

          You are right that the circuit board does not have parts installed per diagram. I do not see the PIN Diode BPW34 on the board.

          https://cdn.badcaps-static.com/pdfs/...8098d5cb9f.pdf
          http://www.emant.com/324003.page
          Using it for Geiger counter is another story.
          See example circuit (SHARP) how it is used.
          Attached Files
          Last edited by budm; 03-16-2015, 02:08 PM.
          Never stop learning
          Basic LCD TV and Monitor troubleshooting guides.
          http://www.badcaps.net/forum/showthr...956#post305956

          Voltage Regulator (LDO) testing:
          http://www.badcaps.net/forum/showthr...999#post300999

          Inverter testing using old CFL:
          http://www.badcaps.net/forum/showthr...er+testing+cfl

          Tear down pictures : Hit the ">" Show Albums and stories" on the left side
          http://s807.photobucket.com/user/budm/library/

          TV Factory reset codes listing:
          http://www.badcaps.net/forum/showthread.php?t=24809

          Comment

          • barry wilkins
            Senior Member
            • Aug 2009
            • 172

            #6
            Re: BPW34 photodiode radiation detector

            Hi, you cant see the PIN diode it is on the other side of the stripboard.
            Ac coupling the diode has stopped the circuit breaking into oscillation,all I need now is decent source of gamma radiation.
            Barry

            Comment

            • goontron
              5000!
              • Dec 2011
              • 4108
              • US

              #7
              Re: BPW34 photodiode radiation detector

              Originally posted by barry wilkins
              Hi, you cant see the PIN diode it is on the other side of the stripboard.
              Ac coupling the diode has stopped the circuit breaking into oscillation,all I need now is decent source of gamma radiation.
              Barry
              crack into a smoke detector.
              Things I've fixed: anything from semis to crappy Chinese $2 radios, and now an IoT Dildo....

              "Dude, this is Wyoming, i hopped on and sent 'er. No fucking around." -- Me

              Excuse me while i do something dangerous


              You must have a sad, sad boring life if you hate on people harmlessly enjoying life with an animal costume.

              Sometimes you need to break shit to fix it.... Thats why my lawnmower doesn't have a deadman switch or engine brake anymore

              Follow the white rabbit.

              Comment

              • eccerr0r
                Solder Sloth
                • Nov 2012
                • 8698
                • USA

                #8
                Re: BPW34 photodiode radiation detector

                Radioactive smoke detectors mostly use Americium which is an alpha emitter. Might be best to detect gamma rays by waiting for a thunderstorm or looking for a CRT and overdriving it...

                On second thought CRTs generate X-rays... but it should be ionizing enough to work.
                Last edited by eccerr0r; 03-17-2015, 03:54 PM.

                Comment

                • goontron
                  5000!
                  • Dec 2011
                  • 4108
                  • US

                  #9
                  Re: BPW34 photodiode radiation detector

                  Originally posted by eccerr0r
                  Radioactive smoke detectors mostly use Americium which is an alpha emitter. Might be best to detect gamma rays by waiting for a thunderstorm or looking for a CRT and overdriving it...

                  On second thought CRTs generate X-rays... but it should be ionizing enough to work.
                  he could just come up here to rocky flats :/
                  Things I've fixed: anything from semis to crappy Chinese $2 radios, and now an IoT Dildo....

                  "Dude, this is Wyoming, i hopped on and sent 'er. No fucking around." -- Me

                  Excuse me while i do something dangerous


                  You must have a sad, sad boring life if you hate on people harmlessly enjoying life with an animal costume.

                  Sometimes you need to break shit to fix it.... Thats why my lawnmower doesn't have a deadman switch or engine brake anymore

                  Follow the white rabbit.

                  Comment

                  • stj
                    Great Sage 齊天大聖
                    • Dec 2009
                    • 30991
                    • Albion

                    #10
                    Re: BPW34 photodiode radiation detector

                    open the window and point it towards Windscale / Sellafield nuclear dump!!!!!!!!!!!!!!!!!!
                    https://duckduckgo.com/?q=windscale&...t-wt&kv=1&kh=1

                    or order something from japan and then test the contents of the envelope!!!
                    Last edited by stj; 03-17-2015, 06:55 PM.

                    Comment

                    • desert-rat
                      Badcaps Legend
                      • Mar 2014
                      • 4103
                      • USA

                      #11
                      Re: BPW34 photodiode radiation detector

                      On the gama rad. you could see if a doc. would fire up an x ray mch. I have found a few circuits for a e.m.f. meter , I am not sure if they really work , but all I would need to test one would be a ghost .

                      Comment

                      • stj
                        Great Sage 齊天大聖
                        • Dec 2009
                        • 30991
                        • Albion

                        #12
                        Re: BPW34 photodiode radiation detector

                        you can buy emf meters for $10 on ebay.

                        it's only going to pickup every coil and transformer in the house though!

                        Comment

                        • barry wilkins
                          Senior Member
                          • Aug 2009
                          • 172

                          #13
                          Re: BPW34 photodiode radiation detector

                          Thanks for your comments ,to get a crt to develop X rays you need something like 25Kv ,the cone is shielded with steel and the face plate is lead glass. I dont have a colour tv with a tube any more.
                          I did see an idea were you ionised a length of wire to attract dirt and dust witch might have enough particles to detect.
                          I think I may of found out why my Fet circuit failed to work ,the diagram showed a JFET ,a similar circuit I saw used a 2N7000 which is a mosfet.
                          On holiday for a while so will carry on in a week or so.

                          Barry

                          Comment

                          • desert-rat
                            Badcaps Legend
                            • Mar 2014
                            • 4103
                            • USA

                            #14
                            Re: BPW34 photodiode radiation detector

                            I would think you could buy some alpha and beta rad. test samples . You can use a muler giger . tube , as all the old giger counters use . I have an old giger counter , it has some small vacuum tubes . It takes a bunch of batteries , like 1.5 for the fil. and 135 vdc , ect.

                            Comment

                            • barry wilkins
                              Senior Member
                              • Aug 2009
                              • 172

                              #15
                              Re: BPW34 photodiode radiation detector

                              Attached a couple of pictures
                              The correct circuit and the results of Am241 using a naked BFY 55 transistor
                              The BPW34 diode I bought just dont work ?

                              Barry
                              Attached Files

                              Comment

                              Related Topics

                              Collapse

                              • Astonished
                                Fixing the Charge Circuit of the Batteries of the DC Motor
                                by Astonished
                                Hi friends of electronics

                                What you see in the video and pictures attached is the circuit for charging the batteries of a DC motor.

                                The problem is that this circuit cannot charge the batteries (3 1800mAH NiMH batteries) any more. When the circuit was OK, its green LEDs lit up one at a time to show that the batteries have charged more. But now that the circuit is flawed, LEDs light up as you see in the video and at the same time successive beeps are heard.

                                Please help me fix this circuit.

                                (the datasheet of the IC: https://pdf.datasheet.live/28...
                                01-28-2025, 06:24 AM
                              • rddube
                                Lenovo L490 Ram voltage circuit malfunction
                                by rddube
                                Hello friends,

                                Looking for some guidance here. The RAM voltage circuit on this motherboard keeps burning out PU301 which is a RT8231AGQW. Copy of the board with the burnt chip attached with some voltage measurements and copy of the schematics also included.

                                I think I've checked almost every component in the circuit, but when I change the RT8231, the laptop starts I have 1.2V on the inductor for about 10 seconds and then the RT8231 goes south and no more voltage on the inductor. All other voltages on the laptop are good, this is the only one conking out for a reason I...
                                07-15-2025, 04:41 PM
                              • Tarot Superstars
                                Short Circuit tester
                                by Tarot Superstars
                                Hello.
                                I have seen a short circuit tester made with 3 * 9V batteries, a voltage limiter component and a resistor connected to the probes of a multimeter.
                                The theory is that the meter becomes sensitive enough to read very low resistances and the lowest resistance to ground on a circuit is likely to be a short circuit in that area.

                                Link
                                The Amazing $1 Short Finder Upgraded! Convert ... - YouTube
                                https://www.youtube.com/watch?v=0eixDdCpiO4

                                My multimeter isn't normally sensitive to very small resistance, but when I put a 1 mega ohm resistor...
                                09-25-2023, 09:11 AM
                              • M1NEBLANK SHOW
                                MSI B250 Gaming M3 Short circuit in CPU power supply circuit
                                by M1NEBLANK SHOW
                                Hello. MSI B250 Gaming M3 board, short-circuit on the power supply. Found a problematic mosfet VQ1
                                (N-PK616BA_PDFN8-HF) soldered it out - short circuit is gone. I replaced VQ1 + VQ5 (N-PK632BA_PDFN8-HF). VQ1 was replaced with PK618. After starting attempt VQ1 is lit again. What can be the problem? In the driver?

                                Schematic and Boardview here
                                ...
                                04-04-2025, 03:57 PM
                              • прямо
                                Viper22A 5VSB circuit
                                by прямо
                                So I have a cheap non working ATX PSU that I was learning to repair a decade ago. At the time, it blew the main fuse, bridger rectifier, NTC, and primary 9A 900V MOSFET. Replaced all except the MOSFET. 5VSB came back online. Then I poked around in it so much, measuring components one by one to a point I accidentally made the 5VSB circuit primary side went bang. Blown the AP8022 (Viper22A) PWM chip, along with a low resistance resistor and the PC817 opto isolator. I replaced them all.

                                In the process of poking around, I also lost a zener diode that stabilize the voltage coming from...
                                01-13-2024, 07:05 PM
                              • Loading...
                              • No more items.
                              Working...