Prototype PCB board

I have too many ideas I want to play with, so it finally struck me that what I really want is a prototype PCB for the HP5065A.

I sat down tonight and hacked up a first draft:

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If I fab this, it will be my first PCB made in KICAD.

I used to use EAGLE, and I love it. EAGLE is amazingly good software - but it is Closed Source, and it is expensive.

KICAD is Open Source and nowhere near as convenient and well-rounded as EAGLE. But after CERN put their weight behind KICAD, it has made great strides in short time, so I’m jumping ship now.

Layout considerations

Having two edge-connectors allows you to use it also as extender board, by adding 15 wires and a connector, that makes it potentially useful also for people who do not want to modify their HP5065A.

If you’re stingy with the space, you might even be able to cram two different prototypes onto the same board, for easy A/B testing.

Or you can use the second connector to bring out test points.

The good thing about a prototype area like this one is that it’s quick and mindless work to hack one up.

The bad thing is that they’re nothing but trouble.

The fab will likely complain about drill-time and charge you extra.

The board breaks easily, being totally perforated.

But worst of all, at least for the present case, there is no way to get a good ground-plane.

A better layout would dedicate the bottom to a continous groundplane, brought up front with regular vias.

On the front there should be convenient IC-footprints for modern chips, at the very least SOIC, in addition to the uncommitted grid.

Finally, if large/heavy components are anticipated, a pattern with throuh-hole pads are a must.

That obviously requires a bit more thought and planning than the quick hack above, but I think the time will be well spent.

Price

PCB-pool quotes €200 for 10 PCBs this size.

If I want to offer other HP5065-nuts to ride my coat-tails at cost, a good envelope and the postage make their price around €25.

phk