MsPacMan

=A0 springy wires jam into via

=3D =A0 =A0 =A0/------\

=A0 =A0 \

=A0 =A0 =A0 =A0/

=3D =A0 =A0 =A0 -------

I used to sit and make little test points myself that were tiny pieces of Teflon sheathed SPC wire which I stripped a bit, then quick tinned to stiffen the stripped segment a bit, then form that into a tiny loop, then re-tin that with it against the non-looped part of the bared wire making a closed, round, non-emissive loop. Then strip the other end carefully so that you get some wire below the loop, but no so long as to be overtly emissive, and tin what is below that, and cut it for PCB insertion. One can choose a gauge that makes for an interference fit on the via so that inserted test points remain during reflow or wave operations..

I would personally hand solder them. Scope probes and meter probes hook right on to the little loops just fine at that point.

I use redundant 32 mil vias for test po>

On a sunny day (Fri, 16 Jul 2010 10:29:43 -0700) it happened John Larkin wrote in :

I have used normal sewing needles, those come in a pack with differnt sizes for a few cents. the tip is conical shaped and will stick a bit. On the other side you can slide it into an isolated wire, or clip the scope on it.

I vaguely remember, from my GenRad days, "pogo" pin ?? ...Jim Thompson

Like this?

A bit large and you'd have to solder your wire to the lug. Not sure how long the springiness will last after xx insertions and removals. Maybe they've got smaller ones.

=A0 springy wires jam into via

=3D =A0 =A0 =A0/------\

=A0 =A0 \

=A0 =A0 =A0 =A0/

=3D =A0 =A0 =A0 -------

get some of the pressfit dil sockets like on page 142 in this:

push the pins out of the plastic form to get single ones

-Lasse

That looks pretty good; I'll try some. Soldering a wire on there is fine. We bought something like 50 scope ground leads for the lab, so I could sacrifice a few. Thanks.

John

I believe Newark carries them.

Digikey has it, too. Search for "keystone test points" and you'll get a nice selection for diameter, color etc. Looks like it is popular, because some types are available in container quantities :-)

By public documentation (see above), you just lost patent rights...

Thanks, I didn't know they carried these. Unfortunately such test points are comparatively large, for 0.040" holes and similar.

Come on Joerg. They're only three for ten bucks. You can afford them!

BTW, we use something similar for less than $.10 each. ...and those are usually deleted when production settles down.

Oops! Just noticed that was the extended price. They're "only" a third of a buck, so they're still in your range (too early). .

I didn't say I can't afford them :-)

They are just a bit large for modern SMT layouts. Technologically a bit long in the tooth.

;-)

We use them on power supplies and a couple of communications lines (RS-422). They're useful for scope grounds.

There once were connectors that would accept a scope tip. Has anyone seen those recently? They were *expensive* but for test jigs they would be useful.

those

Not recently. I often use needles, the ones that come with higher end shirts. You know, where Murphy says that you'll always forget one when trying it on and ... OUCH. Many can be soldered to (not all) and then occasionally I use a rubber band to tug a bit on the cable or the needle so it won't fly out.

The needles are free, as long as you pay the $49 plus tax for the shirt :-)

You mean a Tupperware container? ;-)

Best regards, Spehro Pefhany

I have some coils of silver coated copper. 1 mm diameter are nice for soldering stable test points and 0.4 mm is useful, if you don't have much space (or for dead bug style prototyping). Of course, not as easy and good as a ready made test points with a loop and plastic ring for easier mounting.

you are right, it is easy for me to be wrong when estimating volumens without calculating :-)