QnD workaround because no PCBites at hand

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Continuing the discussion from Milled test point pins?:

Sometimes you get caught without PCBites though… Lego, tape and 2 random springy probes to the rescue…

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(used that to tickle out some data out of a JL chip, educated guess and some measurements made that clear even though that one was filed off)

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Pogo pins are great, it’s just a matter of how to hold them in place :slight_smile:

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true. PCBites are just a fancy way for that job. but when you don’t have them at hand but a big stash of lego pieces there are enough other ways for holding them. Was lazy since i didnt want to play inverted tetris to reach a few boxes of more lego technic stuff, otherwise that solution could have been more complicated, took me a few tries with this ghetto-rigged one to get the connection reliable

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i bought a few of these and then just made my own - https://www.aliexpress.us/item/3256802662340720.html

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Components IC Chip Module Cpu Circuit Board PCB Electronic Production Welding Fixed Test Probe Pressure Needle Burning

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Shared this hack in Iceman’s Proxmark3 forum, so thought I’d also share it here.

While you can purchase pogo pins pre-made into "cable-like" assemblies, pogo pins are ***notorious*** for breaking, and sometimes you can't wait for another shipment. For 2.54mm / 0.1" spacing, it's convenient and easy to have parts pre-made and ready to create an adapter / replace broken bits. Here's one hack I've used:
Materials

  • 2.54mm / 0.1" Dupont Wire Jumper Pin Header Connector Housing Kit … or similar
  • Crimping tool for above, such as iCrimp IWS-2820M
  • POGO pins … search for “P75-E2 pogo spring test probe” (1.3mm head, 1.02mm tube; I most often use conical head)
Create a Bunch of These Parts

  • From the header kit, detach a dozen (or more) of the female-side tin connectors.
  • Hold a pogo pin where the wire would normally be placed, pushing it all the way up.
  • Crimp the two locations, first with 1.6mm and finishing with 1.3mm
  • Optionally, add a touch of flux and solder in place
On-Demand Connectors

  • Grab the size of plastic female dupont-style header that you need from the kit.
  • Populate necessary holes with the pre-made pogo pin inserts.
  • Use dupont style cables to connect to test equipment.
Pin Replacement

When a pogo pin inevitably breaks…

  • gently lift the plastic tab holding the pin in place, and slide out the broken pogo pin assembly.
  • Press the plastic tab back in (deeper than needed) to reset it. If it breaks, make a new connector.
  • Fill the empty spot you just created with a pre-made pogo pin insert.
  • Continue without delays or frustration.
Other Notes

Having the pre-made pogo pin inserts also allows you to create non-standard (0.1") patterns, such as when the test points / unpopulated through holes skip a spot or two.

Total cost is under $40 using Amazon, likely much cheaper direct from China if you can wait. For example, Amazon US lists $6.50 for 100 pogo pins, ~$20 for the crimping tool, and ~$10 for a decent size kit (e.g., 620 piece kit having 20 of 1 x {3, 4, 5, 6}; 40 of 1 x {1, 2}; 10 of 2 x {2,3,4,5,6} ).

If you make 20 or so at a time, it really doesn’t take much time, either.

Pictures

First picture shows the pogo pin assembly (from bottom up):

  • Separate parts
  • Crimped
  • Soldered

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Second picture shows those three newly-minted pogo pins in a 1x3 header … Just add standard dupont-style male connectors.

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(You can also see I’ve used other sizes in the background, including a 2x3 with an intentionally ommitted pin.)

Enjoy!

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