Gamma Spectrometry Forum

Hello Madmax, from what i understood on pmt electronics and experiments.. these caps are reservoirs caps : they are a reservoir of current in case the cps is too high in order to have a better linearity when the cps rise up. These are not decoupling capacitors (in wich case they would be connected t...

Here is the spectrum of the Thorium and the influcence of wood or lead , and with or without the shaper on the 3M load resistance.
Chris.

Hello I'm carrying on making experiments on the different components of my pmt setup in order to understand how things work. So I tried to play with the load resistance value. PMTconnection résistance de charge.jpg The Pdf document about Theremino suggests 1M although many profesionnal doc advocate ...

Thanks very much Tom, thats very informative !! thanks a lot. In fact this afternoon I went to the music shop where they sell these kind of usb sound card or preamp mic interface.. and i got a "scarlett solo Focusrite" @ 192 kHz and playing with both now at home on my laptop with Theremino...

Hello,
Could you please tell me if I got it right : so in the end if I bought a 192 kHz sound card instead of the 48kHz I currently have , will it help to improve the resolution or just allow a higher cps rate ? or both? as the number of bits/pulse is always 16 ....?



CHris.

I've just done the Uraninite spectrum to check if it worked too....
chris.

Hello guys, here is my first spectrum that looks like a spectrum! My high voltage from amazon with an simple RC filter works fine (a few mV ripple but will be improved later). The new proper sound card (@48kHz so far but will be changed for a 192kHz soon) was the key of the technical problems.... Th...

I have a question about sound card sampling rate and results : It might seem obvious to some of you but i'm still asking the question as my budget isnt big : Indeed as suggested before the results are getting better when I set Theremino @ 384kHz sampling rate even if my card is rated at 48kHz. Will ...

you mean setting the 354kHz frequency in Theremino even if the card wont go more than 48kHz? like the software sort of extrapolate the sampling ? My first trials with the new card are indeed much much better ; there is still some noise from the usb port but it seems possible to filtrate it via a usb...

Hello iRad , thats exactly what i realised and whats happened : the nowadays 2022 usb sound cards (the cheap ones) are different from the model Theremino refered to and you're absolutely right about them :( I've received tonight my new good quality (supposedly) sound card but turned out its only a 4...