I'm building a new Hornyak detector for fast neutrons as we noticed some asymmetry in the fusor output (again) and wanted to chase it down a bit with a fairly localized detector - ignoring slow neutrons which are everywhere when a fusor is running. Hornyaks work by letting fast (only) neutrons knock a proton out of some plastic, then letting it energize some phosphor that's more sensitive to charged particles than it is to other things like gamma rays. That would in this case be ZnS:Ag.
It's not a lot of light per neutron, and we want to see them individually, so about the easiest way is to use a Hornyak button on a photomultiplier tube. This means all manner of construction issues to get it light-tight, build the dynode divider chain (this post), shield it from external noises (it's not usually a huge signal) and leakage, and so on.
Turns out that what is philosophically trivial isn't all that actually easy unless you know a few tricks, I thought I'd put a few here.
The writer of one of my Perl books said (sorry, I forget which one but a shout-out to y'all in the community) - that he dies a little inside every time he sees someone mindlessly doing the same 4-5 key stroke over and over again to say, reformat some text. Gee, you're on a computer, it runs programs, the entire point is to automate things like that! There's an analogy in shop work, called a jig (don't gag Jerry, not everyone here is as good as you are at this kind of thing).
I want this detector working more or less yesterday, and I didn't have the just right resistor values in stock (and resistors are so cheap I'd have to figure out a few other things I want to make anything like a minimum order at my chosen vendor). But I had a big bag of ones just half the size I wanted. Soooo...I need a bunch of these, hooked in series in pairs. Yes, I can do this by hand, I'm fairly dextrous for a left handed guy, but...I'm in a shop, it's full of tools that can make tools, darnit - same as being on a computer that has say, perl on it. Soooo...we build a jig for this, since it saves more time than it takes to make, and saves lots of fiddly frustration. Like so:
I just needed a slot and a couple small flat weights. Not shown is the other side, where I tried different slot depths - it's easy on a table saw, and by cutting a few, I knew I wouldn't have to walk back across the shop. So you cut your resistor leads, put them in the slot, and set the weights on them like so, and solder:
And almost before you know it, you're done:
Bonus - as I mentioned in the linked thread, I also made a jig to make the lead cap for the end of the tube, and that the other end hand nice markings on it from my sloppy saw work. I also added that next bit of copper tape and wired all that to the cathode, so that there'd be zero volts across the maybe-leaky glass/cathode interface (this has bitten me in the past) :