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1 November 2013

A Soldermask for free

Filed under: specific — Tags: , , , , , — .. @ 03:08

Here I show your how to integrate some new steps in your photographic PCB-production process.

After the usual step of exposure with a positive of your track patterns & development & etching you just add another exposure with a negative of your solder mask pattern. As a result you get the rest of the etch resist as solder mask to stay on your PCB as protection & solder repellent. The idea comes from a Bungard datasheet.


7 July 2012

SMD Probes DIY

Filed under: specific — Tags: , , — .. @ 21:21

More on the  little “secrets” of SMD – some measurement probes for debugging in awkward places:


As you can see in the first picture these probes are made from thick 1mm hypodermic needles – i got them in the pharmacy around the corner. They were cheap, 10 for a Euro (much less on Bay) – dont hesitate, it´s just a normal product to buy.
In the beginning I used them un-isolated but then found some tubing I removed from PC power supplies. Heating the needle a little bit & some oil as lubricant helped a lot.

But the easiest way to isolate the needles is to use heat shrink tube, that also gives the thinnest probes..

Close-up of a tip:

SMD Probe Tip

A DIY oscilloscope probe & another earlier mini probe isolated with an AWG  18 cable tube:


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