[Amps] full range C vs. padders

[Steve Flood]

My 160m/80m/40m/20m amp design calls for a 250pF Ctune and 1500pF Cload.

I notice some designs use capacitors with the full capacitance range variables, while others use lower-value variables and fixed caps switched into parallel for 80m and/or 160m operation.

Rather than using the full range air variables I built (very large), I also have commercial 25-95pF and 100-800pF air variables I could use for Ctune and Cload respectively (with appropriate voltage/plate spacing).

Space, layout, and component availability is certainly easier with the second option, but what are the disadvantages or pitfalls of doing so?


Steve, KK7UV