LM380 Audio Amplifier using Me Squares

My favourite construction method, with NO GLUE !

I am forever tinkering with circuits of one kind or another. Usually receivers. Etching a PCB for a one off project is too time consuming and hardly cost effective. On the other hand, strip-board is not the best medium for RF construction. I am also not a fan of “ugly construction”. So for many years I manually cut squares and oblongs onto my PCB’s using a craft knife and a steel straight edge. Then I discovered ‘Me Squares’ and ‘Me Pads’. My first few project using these pads took up more space than I had bargained for as the pads were spaced out to accommodate the components. Also it was a bit messy getting just that tiny amount of super glue on the pad. Then one day I accidentally knocked over a half full bottle of glue. It was difficult to put things down for a while !

Later, while building a classic post mixer amplifier, I drew the pad layout on squared paper. The individual pads were just a few mm apart. I quickly realized that if I stood some of the resistors upright I would not need to separate the pads at all. A little further planning and I had the whole circuit module on pads, in one piece. I recommend spending a little time on this, as the result is well worth the effort. Just follow the schematic layout from left to right. Try to get at least one grounded component on each side of your module.

This example uses the 8 pin audio amplifier the LM380-8. Here is the schematic.lm380_schematic

Here is the module built on pads and squares.

lm380_pads

Here is the same module mounted on the PCB. There are usually sufficient components going to ground that NO GLUE is needed to hold the module down to the copper substrate.

lm380_pcb

The grounded components are holding everything in place. I’m sure there will be the odd occasion when a pad will need to be glued down. For me this is a last resort, and I now use double sided adhesive tape if really needed.

Most of the projects posted here are constructed in this way. You should try it, it really works well, and it undeniably look good.

73 from ZL4SAE

 

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