I've been enjoying reading all these stories.  There was a tool that I always hated using, probably not because it was the worst tool but because of the circumstances in which we had to use it.  Back in the good old days we used to build fairly complex ATE (automated test equipment) using massive wirewrapped backplanes.  There were the inevitable shorts or opens which were usually extremely difficult to find in the rats nest of wirewrapped connectors.  Our tool of choice was something called a borescope which was an illuminated optical tube about 18 inches long with an eyepiece on the end that allowed you to get a view down at the pins.  Because of the nature of the troubleshooting you had to be physically in the backplane and sometimes under it and much of the time the unit was powered up.  I remember a time when a dipped tantalum capacitor burst into flames while I was under the backplane and I ended up with a nasty bump on my head because of my reflex reaction.  I can still remember the vivid image of the orange flame bursting through the side of the capacitor!  Suffice to say that I hated using that tool.

Nowadays, I use a similar tool - a USB inspection camera in much friendlier circumstances and it has the advantage of not having your face up next to the tool in case of surprises .

Here's a pic of my inspection cam.

Aaahhhhh, wirewrapped terminals! You just gave me flashbacks!

I had the dubious pleasure of using various bits of GPATE (general purpose ATE) back in my (thankfully infrequent) 'bay days' in the RAF . . . . . .

Some of our kit took 4-5 hours to test the kit and 8 hours to get the damned thing working in the first place. The old 19" rack system for the old Tornado GR1/4 Flight Control boxes (Pitch & Lateral Computer) never got switched off once it was running properly . . . . .

And then you had to reconfigure it for another box . . . . . .  

Back in another lifetime I also worked on ATE for avionics.  That was back in the 70's when we were doing the first cruise missiles.  I was amazed that we actually got all that stuff to work .  Even more amazing that we put a man on the moon.

Of course, even nowadays things only "sort of" work most of the time .

Wow, small world!  In the mid 70's I started in electronics doing a lot of ATE work across multiple systems, for military and avionics electronics.  I then moved into a more specialized corner of the ATE market, designing electronics/software for in-circuit testers for testing PCBs.  I saw a lot of junk out there, as well as some pretty cool stuff.  So many times it was necessary to widen the test limits so much (due to the drift/lack of accuracy) that even bad boards would pass.

ralphjy they have no respect for wire-wrap BTW I do all of my prototyping that way.

genebren We had various issues with one of the modules in the PTR1721 radio, it would pass all checks at repair/test and then fail when fitted to the next highest assembly (the radio chassis). The tolerances of the 3rd line test kit were looser than the actual radio could handle!!

genebren We had various issues with one of the modules in the PTR1721 radio, it would pass all checks at repair/test and then fail when fitted to the next highest assembly (the radio chassis). The tolerances of the 3rd line test kit were looser than the actual radio could handle!!