Hi Hashy!
Don’t be too harsh on yourself.
If I got it right, what happened is that you pressed the tube against the middle clip and that punctured the tube?
The middle connector is there for those that want to use the shorter SI3BG tube, very insensitive, but better to offer it as an alternative.
The SBM20 which is supplied with the KIT, only needs the to far-end clips for support.
Now, if the tube is broken, it lost its internal gases and special pressure parameters, making it impossible to register any counts, exactly like you described. If touching the contacts results in counts, this shows your soldering skills are OK, and replacing the tube will get it working.
Sorry for this, I’ll make sure to add the SI3BG details to the next manual revision. Also, make sure the seller sends you a tested/working SBM20 tube, and not anything else (like STS-5, etc, some sellers are not serious about what they are doing).
And please post some pics, might be useful for others reading this. At least as a warning.
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