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I am planning to buy a photomultiplier tube for my lab experiment but I am not sure how to use it exactly. For eg. I was looking at the hamamatsu HC-120-05. http://mi-lasers.com/wp-content/uploads/HAMAMATSU-HC120_series.pdf

  1. It is written in the datasheet that the operating voltage is -1100V. Is that the supply voltage?

  2. How do you see the output from a coaxial cable.using oscilloscope?

  3. Do I have to use another amplification circuit to see very low light output?

Another one i checked was senstech P30A-03 http://www.sens-tech.com/assets/media/files/Data%20Sheets/P30A_iss2.pdf This one says power input is +/-5V and HV control sensitivity is -1000V. WHat's that?

Anyone who has ever use any photomultiplier please help. Its very expensive, I don't want to buy it without understanding how to use it.

Thanks so much.

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  • \$\begingroup\$ have you read that datasheet? \$\endgroup\$
    – PlasmaHH
    Commented Oct 30, 2017 at 22:27
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    \$\begingroup\$ The datasheet suggests to me that they have already designed the HV power supply for you. From the datasheet, "The high voltage needed to power the photomultiplier is generated with a 10 stage Cockcroft-Walton Voltage multiplier with one stage per dynode." This means (to me) that the "supply voltage" of at most \$\pm 18\:\textrm{V}\$ is the issue for you to worry about. Supply it with the recommended \$\pm 15\:\textrm{V}\$ seen in the figure on the last page of the datasheet. If you are not able to read this datasheet well, get some advice from Hamamatsu! They want you to succeed. \$\endgroup\$
    – jonk
    Commented Oct 30, 2017 at 22:54
  • \$\begingroup\$ You should be aware that you can easily damage PMTs. You may accidentally create very high interdynode currents when an operating PMT is exposed to too much light. The electron bombardment of dynodes release ions and if enough of that occurs then breakdown will also occur. The PMT will just glow. The PMT is then left with an ion-damaged photocathode and filled with gas. A good design can help protect against this and I hope the unit you are considering is safe in this way, or that you will treat it with kid gloves. \$\endgroup\$
    – jonk
    Commented Oct 30, 2017 at 22:58
  • \$\begingroup\$ Finally, I hate to say it but you sound as though you are without any clues. Who told you that you needed a PMT and why did they say so (what do you recall of it?) What exactly is your lab experiment, in detail? Do you know the range of irradiances you are concerned about; the watts per steradian and your optical arrangement and how all that reduces down to the needed sensitivity of your equipment; the wavelengths you are dealing with; etc.? You need to write a lot more, I think. \$\endgroup\$
    – jonk
    Commented Oct 30, 2017 at 23:03
  • \$\begingroup\$ Thanks for all the information @jonk . I am required to measure very low intensity light from chemilluminescence(chemical reaction that gives out light). Pmt is needed to know the light luminosity or wattage that the reaction actually produces so that I can choose appropriate photodiode according to it. \$\endgroup\$
    – Kashish
    Commented Oct 31, 2017 at 15:04

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from what I had gathered from the datasheet that you sent I will answer your questions. in the order that they appear.

  1. the supply voltage is something that is generated withing the tube itself the only thing that you need to is adjust the control voltage.

The text said to the following.

"Monitor the voltage between the white (Control Wire) and the black (0V) the photo-multiplier operating voltage is 10000x that of the control." (Be very careful)

  1. Find someway to bridge the signal wire to a probe and make sure that you have a proper grounding as well.

  2. No the signal should be powerful enough or your equipment should have an external amplifier.

One thing to keep in mind is to wait a bit when you have everything set up to let the tube warm up, warm up time is all so stated in the documentation.

Good Luck.

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