In general, trying it out for a while is far from testing. Testing is what one does with a new circuit once he is absolutely certain it functions as desired and when he wishes to ensure that it functions properly under a range of conditions as specified in the origingal design specification. This means over a range of temperature, voltage, and randomized system noise. It means when it is exposed to a range of prespecified specific events, not intended to be "normal" operation but which it must tolerate. It means long-term (e.g. 1000-hour burn-in)operation under extreme conditions.

If you don't have a fully equipped laboratory capable of producing and controlling all these conditions, you can't "test" a device.

Cut-and-try is a fine method for whittling a flute. It's not so effective for designing and building electronics.

RE