We’ve made it to the 4th video and in this video so moving on from our last video investigating variable frequency filters using analogue switches, we now go into more advanced variable filters using multipliers. As per usual we go through the theory and then show some results from some real circuits, as well as leaving you with some other options for making filters variable.
We also cover some common errors that are made when making filters variable and look at techniques to make the ranges covered larger, expanding to several decades of range.
For some examples covering the initial design of fixed frequency filters, see some of the earlier videos and in the next few videos, we’ll get the PCB assembled and take some measurements on a system which covers multiple decades, working towards a useful bit of lab equipment.
