Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

I Preamplifiers in radiation measurement systems

  1. Sep 15, 2017 #1
    In the radiation detection, it's of common use pulse-type systems, which have a preamplifier between the detector and the amplifier. I have read that the preamplifier primary function is reduction of attenuation of the signal that exits from the detector by matching the impedance of the detector with that of the amplifier. How does this matching helps to achieve this goal?
  2. jcsd
  3. Sep 20, 2017 #2
    Thanks for the thread! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post? The more details the better.
  4. Sep 21, 2017 #3
    I'm not an electronics expert but let me start and others may correct my response if I'm inaccurate.. Impedance matching allows maximum power transfer from one device to another. If the devices are not matched then particularly at high frequencies as contained in pulses the signal is reflected back to the sending device.

    I was always under the impression that a preamp's primary function was to produce a better signal to noise ratio by amplifying the detector signal before sending it out over a usually long coax.

    Also don't amplifiers typically have high input impedance and relatively low output impedance with the coax having its own impedance typically under 100 ohms ? My impression is that in pulse circuits the actual matching occurred at the end of the coax at the amplifier by using a Tee connector with a terminating resistor of the same impedance as the coax.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted

Similar Discussions: Preamplifiers in radiation measurement systems
  1. Ionizing Radiation (Replies: 4)

  2. Neutron radiation (Replies: 1)

  3. Cherenkov radiation (Replies: 1)

  4. Radiated Lead (Replies: 8)

  5. Induced radiation (Replies: 4)