Scope Probe for 0.40mm Pin Spacing

Take a look at what

For me the solution (so far) always came from my wife's stuff: A sewing needle. I even had my own from before we married but I wore those out. Not so much from sewing but from scraping and probing around electronics.

I solder thin wires (connected to a header) to such pins.

I use 'Takaya' probe pins... micro point, super sharp and will go through conformal coating

A small hypodermic syringe works well too, the needles are very sharp and the syringe body makes a handy insulated 'handle'. 0.5ml types used for insulin are good. Difficult to solder, but the hollow needle will readily crimp onto a thin wire.

Actually, these are good for all sorts of things, including using them as miniature crowbars to lift component legs for debugging or complete part removal. I have dozens from a deceased relative.

Cheers

I often use syringes in my work, mostly for oiling difficult to reach shafts, pressure tests, et cetera. Like when the input attenuator shaft on a scope seized up. Once when I wanted to buy syringes at a drug store the pharmacist looked at my arms (I wore a T-shirt). "No, not for that kind of stuff" :-)

I imagine sliding something like two pieces of thin plastic between pins on either side of the pin to be probed could work

or maybe a piece of flex pcb slid in between pins, on side connect to pin the side other isolated

-Lasse

Sunhayato in Japan makes some test clips for that kind of parts. The FP-7S clips are for parts of 0.3-0.5mm lead pitch (0.3mm nominal, allows some additional distance to each other). For details see

Sure, they are not scope probes, but they have connection leads with pin-header type sockets at the end, so one could rig a connection to an existing scope probe without many difficulties.

The prices however are in the "run and hide" range. A set of 2 clips (FP-7S-02) goes for the equivalent of 60$, a set of 10 with 2 holders and a loupe (FP-7S-10) will set you back about 300$.

They also have a 3GHz version of the 0.3mm pitch clips, complete with a 3mm length lead and connection to attach a scope probe (FP-HSP10S1). From the picture, the connection lead on these looks really fragile, even by a very careful Japanese engineer's definition of "fragile", and their idea of "affordable" is around 70$ for one Signal+GND clip pair. The 1GHz version (FP-HSP15S1) looks more rugged in comparison, at least in so far as "rugged" applies to something with spring contacts in the 2-digit microns, that is. There's also a 5GHz version, with no leads at all, but I'm not sure, what one would need to even make proper connections to it. Coax hardlines with

Well, maybe Joerg's sewing needle idea is still the best one after all, and if no sewing needles happen to be nearby, there's still the option of taking one strand out of a bicycle brake cable, crimping it into a thin copper tube except for 2-3mm at the end and sharpening the business end of it to any needed diameter. 100 micron or so should be possible.

Regards Dimitrij

I use two insulin syringes per day, and have a couple sharps containers full of them to be disposed of. I found a use for the plastic caps over the plunger. They fit on F connectors, to protect the threads.