The SI-3G and the SI-1G are nice small tubes to carry in an every day pocket geiger counter, just to carry it every where. They are pretty insensitive so, if you hear a slight increase in the click rate, you can be sure the object (or the place), it´s above normally radioactive.
thats a very low current but It´s posible, try the circuit in techlib, with a little tunning I think they can reach that value. And use as many mosfets as you can (instead of bipolar transistors) , and CMOS gates, their power consumition during a steady state it´s "almost" cero. a CD4093 I think it could be used as an oscillator and level detector.
@fuuturist Try working with the electrolytic cap. I use that circuits without regulation. I found out, that the voltage doubler it´s not generally necessary, 1 diode and 1 cap it´s enough to get 400v using an isolation transformer from a modem.
Another low power solution it´s to use a variable duty cycle oscillator and a large inductor. Then tune de values of frequency and duty to get the minimum working voltage for the tubes.
fuuturist what is the v of si-3BG? thanks
88enri88 3 days ago
The SI-3G and the SI-1G are nice small tubes to carry in an every day pocket geiger counter, just to carry it every where. They are pretty insensitive so, if you hear a slight increase in the click rate, you can be sure the object (or the place), it´s above normally radioactive.
Im bulding one probably with a SI-1G these days.
tesla242 11 months ago
@tesla242 I'm trying to make a small GM counter that draws only 0.3-0.5mA, and when count rate increases alarm will start screaming!
fuuturist 11 months ago
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tesla242 11 months ago
thats a very low current but It´s posible, try the circuit in techlib, with a little tunning I think they can reach that value. And use as many mosfets as you can (instead of bipolar transistors) , and CMOS gates, their power consumition during a steady state it´s "almost" cero. a CD4093 I think it could be used as an oscillator and level detector.
tesla242 11 months ago
@tesla242 Yes, I will use Carl Wenzel's shematics. This is also his oscillator, but power consumption is too high - about 1.5mA
fuuturist 11 months ago
@fuuturist Try working with the electrolytic cap. I use that circuits without regulation. I found out, that the voltage doubler it´s not generally necessary, 1 diode and 1 cap it´s enough to get 400v using an isolation transformer from a modem.
Another low power solution it´s to use a variable duty cycle oscillator and a large inductor. Then tune de values of frequency and duty to get the minimum working voltage for the tubes.
tesla242 11 months ago
Comment removed
tesla242 11 months ago
Comment removed
tesla242 11 months ago
@fuuturist I just found this: eetimes.com/design/power-management-design/4009593/Bias-supply-powers-low-power-Geiger-Mueller-tube
The desing claims a quiescent current of 80uA, quite impressive. Too complicated for my, but could be usefull to you if you want to cut down on power.
Sorry with the repeated messages, I have troubles pasting the link
tesla242 11 months ago
@tesla242 wow -_- I'm amazed! I will try this! Thanks!
fuuturist 11 months ago