[Boatanchors] Switched capacitor filter - was Autek QF1 Filter pots

[Dale Parfitt]

 On the topic of peaking and notching. I have one of the Alpha Delta Variable Response Consoles (VRC).
https://www.universal-radio.com/catalog/speakers/2450.html#:~:text=The%20Alpha%20Delta%20Variable%20Response,integral%20part%20of%20the%20system.
It uses a ported speaker and active circuits. Fabulous AM/SSB speaker. But I  primarily  bought it for 1296MHZ EME. Its peaking filter is beyond what I  find in current rigs- including my K3.
I have had 3 over the years. Their only  issue  is the pushbuttons. Because most likely  would not be using the peaking and notching switches that often, they tend to oxidize. They are  an odd switch and I have never been able to find a duplicate. But DeOxit and lots of exercise fixes the issue. On one I bought the  speaker had an open voice coil. Parts Express had an identical replacement- how often does that happen on a 40 or so year old piece? My understanding is that the  audio profiling circuits are indeed switched capacitor.

Dale W4OP