Geiger tube symbol


The v4 device library has a d_radiation component with squiggly lines.


I’ve been tinkering a bit with the schematic symbol for this.
Does this look acceptable?
I put it next to a transistor for size comparison.

The squiggly lines were easy.
Now I’m fighting to put this thing in it’s own lib.

My intention is to drop it here and donate it to PD.
Installing / working with git & making accounts is a bit too much for me at the moment I’m afraid.

Edit 2:
I think this is it:
geiger-muller.dcm (146 Bytes)
geiger-muller.lib (876 Bytes)

Edit 3:
Oops, the “.dcm” file hase some unwanted text in it.
I’m not sure what those “D”, “K”, “F” markers mean. Time to do some reading I guess.

EESchema-DOCLIB Version 2.0

$CMP Geiger-Muller
D P-JFET transistor, drain/source/gate
K transistor PJFET P-JFET
F ~

#End Doc Library


The Geiger symbol I made was moved to the sensor lib: #1502

Why in it’s own lib? I understood from the discussion it should be in the sensors lib.

I can do the git work for you, if you want.


The only reason to put it in it’s own lib is so I can post it here, and it can be processed further.

I think the files I posted are all that’s needed.
I modified the symbol from a jfet (almost everything redraw).

Some stuff in .dcm file remains, and I was reading up on file formats just now on what to replace it with.

While we’e at it. the symbol with the extra dot for the outside connected to the negative electrode seems also logical to add to the lib.

I don’t know what to do with the greek letters. Maybe add a text field, or all separate symbols? That would be around 2 x 10 = 20.

I love standardisation as in the KLC, but I’m not too familiar with the contents of that file. If I had more experience with this I might want to make some changes, but as a start it looks quite good, ans pins are on 100mils grid.


So, your files are ready to be submitted to the official libraries @paulvdh?

I think there’s no need to add them to the symbol. What you use the final product for is net a concern of the schematics.

I think that’s how we should proceed:

  • add this new symbol to sensor lib, naming it Geiger-Muller
  • rename the symbol I made to Geiger-Muller alternative, or something like that.

What do you all think? I’m familiar with the git commands and have some free time to do it, if you need.


As always I’m having some dificulty focussing. I intend to clean my symbol up a bit (Add descriptions) and also add the other version with the dot on the housing.

I also want to check with the KLC and update my symbol.
Reading the KLC is on my todo list anyway.
If I can keep focus I will post an updated new version within a week.
If I have have not managed to do such a (simple) thing in a week, then it probably won’t happen, but you at least still have the symbol I posted earlier.


Kicad 5.1.0 is almost ready, when that happens they will get the symbols in the github and tag as 5.1.0 also. It would be great if we update the Geiger symbol before that :slight_smile:

I’m also trying to understand KLC, i’m new to it. If I understood correctly, we will have 3 symbols? The version that is already there and your 2 new ones? How should they be named?


This is about as close as I can get it.

Geiger_Muller.dcm (426 Bytes)
Geiger_Muller.lib (1.7 KB)


  • Increased cicle size to same as for transistors.
  • Added 2nd component with the dot.


Symbol Libary Editor / Symbol / Properties

  • Description: Geiger-Muller tube
  • Pin names “C1” and “C2” (IEC document uses: One “collector” connected to enclosure).
  • Keywords: nuclear ionising radiation sensor geiger counter tube
  • Documentation:–Müller_tube

Some doubts about:

  • Options, show pin numbers by default?
  • Aliases, anything to add here?
  • Footprint Filter is empty, anything to add here?

I’ve named my 2 symbols “Geiger-Muller” and Geiger-Muller_generic".
The KLC does not permit spaces in names, and “Geiger-Muller_alternative” seems like a proper name to me for the other symbol


Aliases do not make any sense at all for generic symbols. They are only useful for when your symbol should represent exactly one part.


I want to make symbols like you when I grow up! They look very nice!

For the footprint, we should leave it blank. There are so many different Geiger tubes and some of them have a casing with the wires soldered directly to the terminals.

About the pin names, what about cathode and anode? I always confuse both of them, I prefer plus and minus :smiley:


I was not sure if Anode / Cathode were the right terms here, but Wikipedia uses them in the description of a G-M tube:

The chamber contains two electrodes, between which there is a potential difference of several hundred volts. The walls of the tube are either metal or have their inside surface coated with a conducting material or a spiral wire to form the cathode, while the anode is a wire mounted axially in the centre of the chamber.


About remembering Anode / Cathode. In my langurage Kathode is often written with a K.
If you put the A and K together like in the picture, it resembles a diode.

I’ve looked at a buch of diodes, and the firt I looked at (pspice:DIODE) the pins were named backward??? Afraid to loose my sanity so I checked 5 or 6 other diodes and those all have pin name “A” for the side with the triangle, and K for the side with the stripe.
K and A folows normal convention and those seem to be better names.
You can easily change them in the library editor by hovering over a pin and pressing "e"dit.


To be honest i thought the library name would already be enough of a hint that these symbols are specialized for simulation. Now you tell me not even a warning in the description is enough?


At that moment I was only looking for pin names on Diodes.
I had not read the description:

“Pin order incompatible with official kicad footprints”
I had not even noticed it was a diode from the Spice library untill I looked up the library name to add it to the post. Tnx for the confimation the Spice symbol is “weird”, so I can relax a bit and don’t have to loose more of my sanity.

The more relevant part of my previous post is that Anode and Cathode names do also apply to G-M tubes according to Wikipedia.


Not having a hard vacuum inside is not a good reason, what about gas filled thyratrons?


We should discuss this in a bar. Sounds like a really awesome topic with a beer.

What do you mean? Are you talking about the lib name?

@paulvdh, your symbols are ready to go to the official repo?


I am saying that there are devices, always considered to be valves or tubes, that contain some gas by design
Geiger tubes are similar.


That was why I initially considered the Geiger tube a valve. But the discussion here convinced me to move it to sensor.


This is one of the reasons why we normally do not discuss such things over here at the forum.
That is what github issues are there for. (An issue at github will be mainly handled by the library team. Whereas here you did only get very limited input from us as most of us are not here. And i have a policy of not discussing library maintainance stuff over here. Main reason is that it does not reach the full lib team and it will be forgotten.)


I’m not sure wheter E1 & E2 for the pins are OK, or K&A would be better, but I’m finished with the Geiger symbol. Maybe the Kicad Library team knows.

I also agree with Rene’s last post. This is quite inefficient.
In a lot of ways It would be better if I had launchpad & github accounts and learned how to work with Git. These are on some of my ToDo lists, but I’m having some difficulty in selecting priorities. Often I can focus just long enough on a single subject to get a post finished.


You are totally right, Rene. When I started this thread my intention was not to discuss making new symbols, but it become that. I created an issue in GitHub to discuss it.

@paulvdh if you have an account in GitHub, I can help you in the process of opening pull requests to add your symbols there so you get the proper credits there. Otherwise I can mention you in the commit message.