The Art of Custom Test Jigs

A look at some custom bed of nails automated PCB test jigs from Redback Test Services at the Electronex 2022 trade show.

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#ElectronicsCreators #Electronex #Testing

[flymypg]

When I was on the development team for an ultra high speed digital video camera we had some extreme digital and analog testing requirements for our boards, both empty and partially/fully stuffed, and the time needed for firms to create a dozen custom board test fixtures was unacceptable. In concert with our local board house we launched a hair-on-fire project to build our own, using as much off-the-shelf equipment as possible. I got to write the test control and analysis code then script all the test equipment over a diverse collection of interfaces (GPIB, RS-232/485, parallel digital, etc.).

That was my first exposure to production line systems, and ever since I've tried to design poducts that production test techs would love. Not just DFT and DFM, but also looking at test system design and usability, and also ensuring the production test systems would return actionable data all the way back to product engineering, essentially ensuring QA/QC teams never get too far from the product engineering development teams.

I normally developed high-end low-volume niche products (mainly instrumentation), where "foreign production" meant Mexico (and fun day trips). It was a shock when I worked on my first product that needed Asian production to ensure adequate profitability in a competitive market. It was straightforward to design and build the production test equipment here in the US then send it to the remote factory. The real problem was the cost of COMMUNICATION DELAY. Dynamically interacting with folks on the other side of the planet was punishing for everyone involved.

The remote plant consistently failed to produce shipable product. In a panic, we flew some of their folks to our facility, then some of our folks few back with them to their facility. An expensive step in terms of both money and time that had to be amortized over the production run, significantly cutting into profits.

For our follow-on products we found a nifty solution: We worked with an Asian board house that had a local pilot production line that PRECISELY matched the volume production lines they had in Asia. Once we had local pilot production working as needed, they handled everything else. That house soon became our DFM/DFT partner, with their production engineers having a seat at our earliest product design reviews, independent voices who weren't afraid to give brutal feedback.

[hanvk]

That optical fiber LED tester is a brilliant idea.

[brainiac]

Thanks so much for the throwback to the beginning of my career, Dave!
For the uninitiated, and to stated the obvious, these are worth every penny in a production environment as the prevent damage and unwanted handling. ICT every boards coming out of the production lines (Pick and place/oven/other manual operations/visual and/or automated inspection). Test Pass, go to functional test; Test fail, don't plug it in, send it to repair cell/team (electronic production floors are usually divided into cells) and prevent damage to other components. Once repaired, board goes back to ICT or functional test.

[cinobro]

Would love to see some more content from the

[bartoszkazmierczak]

oh geee, it's been a while since I saw someone write anything in visual basic

[TilmanBaumann]

Love the plague mask.Would wear if I was forced to mingle at the trade show

[donepearce]

Very capable tester. My only quibble is with the hinged top. I prefer to see the top drop onto the board vertically.

[envisionelectronics]

I design boards for our in-house testers along with the standard products. Cool to see the end products here as I often never see where my designs end up (often secret facilities!)

[kevincozens]

That booth takes the prize for best freebie with the pogo pins.

[WacKEDmaN]

cool bits of gear!
..mates mask is perfect for the times..amazed i didnt see more wearing them!

[SoYFooD]

i wire/build thees things for a living, and let me tell u thees are the simple ones.
getting programmers and JTEG involved is where the real fun starts.
getting 5 different units of equipment to go to 7 coax headers and not getting interferences, signal drop or reflections is hard.
especially when the hardware u are working on is better than the hardware it is testing.
pneumatics are also fun.
for connecting and disconnecting during a test, or inserting big 400 pin connector.
punching buttons or touchscreens.
hardware to pouch USB port in to there over current protection.
and then having to install a WiFi and Bluetooth module and hope u get a signal threw. (u may have to put it on the outside to have any hope of getting a signal).
that is wat gets me up in the morning.

and if i am lucky i may get to make one that runs 600AMPS and needs water cooling.
that will be a new one for me.

ps ATX is better than ingun.

[cambridgemart]

Are there any non-custom bed-of-nails test jigs?

[njtrigg]

9:05 Oh.. pogo pin brush ! I want one for some strange reason.

[KeritechElectronics]

Makes me think of all these little test points on a backside of the Raspberry Pi.
A thing of beauty is a chicken dinner.
Send one of these beard brushes to Clive! :)

[wpherigo]

Huzzah for Australian tech industry. Hope Australia really builds as much technical independence as possible.

[SigiCZ]

Some test jigs, we design at work (automotive industry), have over 1500 pins (yep 1500 not a typo) with over 1600 tested components. Stuff like that goes expensive fast :) Ingun is good but we preferred ECT and now we use in house solution.

[SubTroppo]

I am sure that plague doctor mask would suit Dave as well. Maybe a special decoder would be required for the audio to bring Dave's voice back to proper Strine.

[McTroyd]

I'm sure the steampunk crow mask is a design requirement for any testing jig! 🤣 Love that genius fiber optic solution for checking LEDs. 👍️

[mike.burdis]

Can the LED tester detect color as well? Been doing this a while and never seen that idea. :)

[BlackSoap]

I had to repair the boards for a pool chlorination and pool heater. The manufacturer authorized technicians have zero way to diagnose individual components, their only option is to replace the whole board. $350 board scrapped for a $0.70 relay, or a $2.00 thermistor. If the board throws a code, the technician replaces the board, and the manufacturer doesn’t want it back. I saw one brand new board fail on install, because of a relay. Pretty bad when the manufacturer is replacing a part, under warranty, and the new part is bad.