Nuts and Volts

switches in place of fuses, as they reset themselves and do not require replacing if the current rating has been calculated properly.

Creating Opens

Just as important as a good connection is a proper open trace. I have seen some opens created by a space barely wider than an Xacto blade thickness. These may work at first, but as the Vero ages it shrinks. So, what was an open is now a bothersome intermittent headache.

When creating an open, I recommend removing one hole width of copper. Smaller widths will work but are not as visual or consistent when compared to removing a “whole” hole width.

The use of a two- or three-pin header gives the option of selecting which function you want by using a .100 shorting clip. I typically use four two-pin headers on my Vero development boards; here, one selects between Port B0 and INT (Interrupt). Other uses could include selecting whether an input is pulled up or down.

MOunting VerO

Pictorial example.

beefing up the copper traces with solder. Of course, you must take care not to short out adjacent traces. I’ve seen almost invisible solder strands short traces out. It is a good practice to run a small slot screwdriver between the traces, followed by a hard brushing of the finished solder side with a stiff horse hair brush. Of course, give it a visual check for shorts, cold solder joints, missed solder connections, and areas that should be beefed up with solder but were missed. It is also a good practice to “ohm out” power for shorts. Do all of this before powering up for the first time.

When calculating a fuse size for your project, consider all high current devices and current surges. Incandescent bulbs will produce a current surge until the filaments heat up and offer resistance. The use of a slow blow fuse here may be required. For most of my Vero projects, I use poly

52 June 2013

Mounting Vero board in project enclosures can be accomplished by custom cutting it to a size that will fit the circuit board receiver slots inside the case. This makes it easy to remove for servicing. Be sure to use the proper size case to avoid a crowded Vero board circuit (refer again to Figure 2). Other methods include using standoffs and drilling holes to accommodate them.

If you’re not using the five solid traces on the edge, this is a good place to drill the holes. Some designs are too small and one must drill the hole traces for mounting. Remove enough copper so nothing shorts to the standoffs, and don’t drill too close to any edge. You would think this is a clear concept, but I have seen many Vero problems from not addressing these issues properly.