This project aims to fix a problem that arises pretty often when working on electronics projects. A signal you are dealing with is too small and you want to amplify it before looking at it on a scope or feeding it into an ADC. Most of the time the only option you have is to start rummaging around in the parts bin looking for an op-amp, resistors, bits of wire, and a breadboard. Then you put it all together and power it up only to find it doesn’t work so you spend ten minutes troubleshooting then finally find the loose wire that was causing the problem. Only then, finally, do you have your amplified signal.
Over on Hackaday.io, user Radu Constatin has made a configurable amplifier board that would be perfect for amplifying the majority of low amplitude signals a hobbyist is likely to come across. The specifications of the amplifier includes a user selectable gain of 1-9000, a 145MHz gain-bandwidth product, a 3.3-26V supply voltage range, and it can be configured as an inverting or non-inverting amplifier.
This really seems like a handy tool to have that isn’t already out there as far as I can tell. There are plenty of audio amplifiers with variable gain but normally the gain range and bandwidth is too small to be used as a Swiss army knife type amplifier. This board isn’t currently for sale on Tindie but Radu does mention he is thinking of selling it on his Hackaday.io page. If you want one, let him know and maybe he’ll get around to selling some. If you can’t wait, he also has the schematics included in the build logs so you could roll your own board. The one change to consider would be get rid of the BNC connectors and put in some screw terminals so whatever wires you are working with you can hook them up with no hassle. Cool project Radu!
