I figured at some point I'd need to build a low pass filter, so this seemed like a good time. Looking around, the CWAZ lpf design seemed popular, and I found this pdf from GQRP on how to build one.
I realized I was running low on called-for T37-6 toroids, as I used some in the DC receiver. But then I remembered I cut one out to replace the VFO with the AD9850. And it was already wound just like I needed! How often does that happen? The other two were fast to wind, and I picked out the capacitors from my junk box.
I hooked it up to the amplifier and looked at the output
So, it looks a lot better. Need to do some more experiments, but maybe ok?
P.S. I finally found out that "CWAZ" here stands for "chebyshev with added zero"
I hooked it up to the amplifier and looked at the output
Without filter |
With filter |
P.S. I finally found out that "CWAZ" here stands for "chebyshev with added zero"
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