My own experience with "solderless breadboards", which of which I've had several for 30+ years, but which I very seldom use, is that they're OK for such things as voltage regulators and other circuits operating at frequencies up to the low audio range, (~5 KHz or so) but not really much beyond that. Moreover, I've found that circuits built on "solderless breadboards" may work one day and, despite the care taken not to disturb them, fail to work the next. Aside from connection integrity issues, I think the power distribution opportunities are so limited that these are really a waste of time for large devices or circuits with more than 4-5 components.

That MAX232 is a pretty noisy component, and can cause your Vcc-Gnd noise to be pretty large, which is why I recommended you put a low-value resistor in series with its Vcc, with a substantial decoupling cap on the MAX232 side of the resistor.

I haven't wired that circuit yet, as it's tax time for us here in the U.S. and I just got the last bit of information I need to start on the annual tax forms, ... <sigh> ... but I do hope to get to that this morning. It shouldn't take more than an hour or so.

RE