It is best to use the DRA818V VHF voice transceiver module with a low pass filter.
Since I'm building a VHF/UHF transceiver using the 818V and 818U modules, the VHF low pass filter was missing from the build.
This design was based from the one here and only some small values changes made , I placed adjustable cap's on the center elements (the 56pF), so used 10-60pF trimmer cap and used 32pF on the ends (10+22pF parallel).
Schematic:
After build did some measurement on the spectrum analyzer:
Final iteration of the trimmers:
Attenuation at 200Mhz:
Filter shape from 100 to 300Mhz without normalization:
...now I need to finish the remaining of the transceiver..
Have a great day!
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