Best way to probe fine pitched pins - Page 1
Forum section: electronics / beginners

author: apelly
author_rank: Unknown
timestamp: November 17, 2013, 03:37:20 pm
content: I'm considering sewing needles...Any better ideas?

author: Unknown
author_rank: Unknown
timestamp: November 17, 2013, 04:15:52 pm
content: What do you consider fine pitch? I consider 50 mil pitch coarse and easily probeable with standard probes / clips. Anything less requires special tools.This pagegives a decent overview of clips designed for various SMT packages. The EZ-hook / Tek probes are fine down to 50 mil, below that you want what that page describes as 'high-end probes'. For browsing I like a sharp spring-loaded tips that allow you to exert less force without having the probe slip, for example the Pomona 6341 / Fluke TL-910 leads, Pomona 72923 probes (pretty sure these are not made by Pomona, they require 2mm leads) or Hirschmann Prüf 2610 probes (though the long distance between handle and probe tip is annoying).

author: rolycat
author_rank: Super Contributor
timestamp: November 17, 2013, 04:37:07 pm
content: If you are on a budget but want something finer than standard probes, needle probes like these may fit the bill:http://cpc.farnell.com/1/1/100996-test-probes-needle-red-black-72-9320-tenma.htmlOnly a couple of NZ$.

author: Unknown
author_rank: Unknown
timestamp: November 17, 2013, 05:07:43 pm
content: Are these any finer than the standard 0.080" (2 mm) probes typically shipped with DMMs? The drawing appears to indicate they're not.

author: apelly
author_rank: Unknown
timestamp: November 17, 2013, 05:12:57 pm
content: Quote from: alm on November 17, 2013, 04:15:52 pmI want to have a poke around a qfn-32 on a netbook motherboard. If that's not the problem then there's abunchof stuff around .3mm pitch.The issue isn't so much the money for new probes (although the big guys really piss me off with their prices in NZ) it's more about the convenience of being able to get somethingtodayThanks for the pointers guys.

author: rolycat
author_rank: Super Contributor
timestamp: November 17, 2013, 05:19:44 pm
content: Quote from: alm on November 17, 2013, 05:07:43 pmHmm.. Probably not. They looked similar to my Fluke TP88 probes, which are 1mm in diameter and have very sharp points, but I don't own the Tenma probes.

author: ovnr
author_rank: Frequent Contributor
timestamp: November 17, 2013, 05:29:26 pm
content: I've got a pair ofPomona 6341probes, which are excellent for this kind of thing. Highly recommended, if a bit pricey ($40).

author: RRobot
author_rank: Regular Contributor
timestamp: November 17, 2013, 05:32:12 pm
content: You can buy an assortment of SOIC/PLCC and other test clips as well. Kinda expensive, but handy for some standard packages.For instance:http://www.pomonaelectronics.com/?i=prodmain&getDetails=&parent=ICCLIPorhttp://www.tequipment.net/PomonaTestClipsIC_QFP.asp

author: rolycat
author_rank: Super Contributor
timestamp: November 17, 2013, 05:44:54 pm
content: If you need a solution right now I've just tried clamping a sewing needle to a probe tip with some heat shrink tubing and it seems to work surprisingly well. I imagine the useful working life is rather limited, though.For very fine work, a set of test clips recommended by another forum user is here:http://www.rapidonline.com/Cables-Connectors/Smd-Test-Probe-Set-17-2576/?sid=e948704c-4952-4d2e-a567-d83276a7a1f4This is a set of eight smd probes which clip onto pins down to 0.2mm pitch.

author: Unknown
author_rank: Unknown
timestamp: November 17, 2013, 06:00:34 pm
content: In a pinch I've also clamped a sewing needle / pin in a crocodile clip.I believe PJP is the original manufacturer for the Pomona 70000-series SMD probes/clips.Theseare the same as the Pomona 72923 probes I mentioned.

author: apelly
author_rank: Unknown
timestamp: November 17, 2013, 07:02:08 pm
content: Quote from: rolycat on November 17, 2013, 05:44:54 pmJust gave this a go. Awesome idea! It is indeedsurprisinglygood!Quote from: alm on November 17, 2013, 06:00:34 pmNowyou tell me!But seriously, you can never beat the proper tool for the job. I'll order something decent this week. That first set ofPomona 6341'slooked good, also the set fromRapidonline Smd Test Probe Setthat rolycat suggested (URL corrected)

author: pickle9000
author_rank: Super Contributor
timestamp: November 17, 2013, 10:03:44 pm
content: Pogo pins work well.

author: JuKu
author_rank: Frequent Contributor
timestamp: November 18, 2013, 06:47:36 am
content: I have a sharp probe, can't remember where I bought it, but...I have an Einstein action figure (seriously!) with a rubber band attached to his hand holding the probe. He leans over and holds the probe for me, freeing both my hands to operate the scope or the computer (USB logic analyzer, giving commands to trigger what ever I try to measure etc).

author: pickle9000
author_rank: Super Contributor
timestamp: November 18, 2013, 06:50:16 am
content: That deserves a picture, while probing.

author: amyk
author_rank: Super Contributor
timestamp: November 18, 2013, 07:55:39 am
content: Quote from: JuKu on November 18, 2013, 06:47:36 amGenius!I've used needles embedded in modeling clay before, but now that I think about it, action figures' moveable appendages may actually work quite well...

author: apelly
author_rank: Unknown
timestamp: November 18, 2013, 09:00:05 am
content: Pfft.Eienstein?I haveSpiderman!

author: GreyWoolfe
author_rank: Unknown
timestamp: November 18, 2013, 12:11:54 pm
content: I have a set of leads that i made that has very small brad nails soldered into the alligator clips to assure continuity.Tom, NW0LF

author: flatmax
author_rank: Newbie
timestamp: November 28, 2017, 09:59:49 am
content: Hi there,This is 0.1" but is similar to what you need ... very handy for prototyping !https://www.kickstarter.com/projects/1250664710/pcb-quick-connect-clip-40-pin-raspberry-pi-compati/?ref=eevblogMatt

author: Brumby
author_rank: Unknown
timestamp: November 28, 2017, 11:30:46 am
content: Quote from: flatmax on November 28, 2017, 09:59:49 amOnly 4 years too late ....Kinda missed the "today" requirement ... and the target geometry.

author: jmelson
author_rank: Super Contributor
timestamp: November 28, 2017, 08:09:49 pm
content: Quote from: apelly on November 17, 2013, 03:37:20 pmI have made converters with a .080" pin jack soldered to sewing needles. The problem is most sewing needles are EXTREMELY hard to solder to. I put the needle against the contact of the tip jack and wrap with wire, then glob solder over it all. It usually holds together, looks awful, and sometimes the needle works loose. But, it is great to be able to poke it onto a single lead of an 0.4mm pitch chip.Jon