[sdiy] Analysing 4-stage RC filters without the hot air

[Timothy Daugard]

On 3/21/2016 5:14 PM, Tom Wiltshire wrote:
> Yes, it was me. I was struggling with using impedances to analyse these things. It's ok for simple cases, but I couldn't get more complicated things to come out at all. This wasn't due to tedium - I was using the computer to do the sums. One thing I never got entirely clear from the discussion on the list was whether the impedance method actually *works* in more complex cases (in which case I had errors somewhere) or whether

The trick I found to doing this with my spread sheet was that you had to 
keep everything as a complex number and use imaginary math functions in 
the spread sheet. I started with 0 phase angle signal input to the array 
and then convert the output back to a real output graph.

Tim Daugard