Finished Interpolators

The PCBs have finally arrived!

The 0.8mm board thickness was important for this design since I wanted them to fit between the connector pins.  For some manufacturers a non-standard board thickness can get very expensive, but the Chinese fabs seem to do them at no additional cost.  Here is a test fit of the board inside the connector housing.

The first step is of course to solder the components.  There aren't too many components and the board is double sided so I did it by hand.  The passives are mostly 0402.  They are small but not particularly difficult to solder.

And finally the board is soldered to its connector.  The middle row of pins is obscured by the header pins, but a fine tipped soldering iron can still get at them.

After finishing the connections I quickly tested each interpolator.

The most time consuming part of assembly was attaching the cable just because there are a lot of connections to be made in a very small area.  I used foil-shielded cable with the drain wire connected to the backshell.

Finally, here are the two finished interpolators next to an original Renishaw unit.

The new interpolators are much smaller and will simplify the wiring.  It's kind of funny to think about how much work went into a nondescript extension cable.