I’ve been building DIY stuff for my customers here in Japan and among them, of course, Ambika (renamed Pherkad).
Anyway, just wanted to let you know that I have slightly upgraded the SMR4 and 4P filters.
It is now possible to switch between 4-pole, 2-pole and 1 or 3-pole.
In the filter menu, only LP was active with those filters.
Now, BP and HP allow to switch between 2 more slopes.
BP= 1 or 3-pole (I have added a jumper on the PCB to select one of them)
Here is what the SMR-4P (P for pole…) looks like:
I have no pictures of the 4P mk2 because I’m still waiting for the 1st batch of PCBs to arrive.
The upgraded filters can be installed in any standard Ambika/Tubika/Pherkad with no modification.
I can sell PCBs or prebuilt boards if interested.
For those who want to make their own PCBs, the Eagle files will be available for download soon.