I build audio projects and small logic control circuits using point-to-point on perfboard (see pic of a recent build).
As you can see this allows me to select wire gauge in accordance to the currents at various parts. When the board is finished, tested and washed I spray paint a clear enamel on the underside. I have built circuits running up to 450V like this without problems, but these are all low frequency projects.
Now I want to build a switcher-style power supply running at 50kHz. For the moment I am only in the exploratory stages as this is terra incognita for me. Is this building method any good for medium frequency work? I seem to recall having seen HF projects built in dead-bug fashion without issues, that can't be any worse no?
The only potential issue I see could be parasitic capacitance between the copper pads. If it is a problem, I could dissolve the unneeded pads using etchant - I have done this for boards that are connected to mains in order to reduce the potential for arcing. This is done before soldering parts - I design my boards with autoCAD so I know in advance which pads need to be kept.
The second point is about the use of a ground plane; this seems mandatory for switching circuits. I can implement it with a piece of plain PCB stock under the perfboard with drilled pass-through holes for the few pins that need to connect to it but there would be a space of almost 1/8" between the two boards, can this be a problem? If so I can place the plain PCB stock on a spot that isn't under parts so it is in direct contact but it will be of smaller area of course.
Alternatively, could a large-gauge piece of wire be used instead of a ground plane? If a low-impedance path is all that is needed that could fit the bill. A 18AWG wire has as much copper as a sizeable PCB plane no? There might be problems due to skin effect in the wire though...
I could etch a bona fide PCB but I'd rather not - I hate drilling dozens of holes using those crazy-thin drill bits, and I'm not convinced at all about consistancy of home-etched PCBs tracks physical/electrical properties. This is the reason I build point-to-point on perfboard.
Sorry for the long post and thanks in advance for any help! -Joe