I use RM8 ferrite cores as signal transformers in the range 10kHz to100kHz. It's a half duplex system so is switching between transmit and receive.
There's quite a lot of variability in the audible noise from these, some you can barely hear, others there's a pronounced clicking as transmit starts.
These have been hand wound by me and others for prototypes. Would a 'proper' transformer manufacturer pot or encapsulate these by default?
The cores are ungapped and very sensitive to assembly - measure the inductance, take it apart and re-assemble and you get a different inductance. Is there some recommended way of putting these together, for example cleaning the faces with something, or using some sort of glue?
I don't want a toroid, thanks.