Via Southgate: WinRFCalc

https://hollandshielding.com/Windows-RF-calculator

offers a free of charge RF toolbox with many interesting RF calculators and analysers can be downloaded, offering the following capabilities

Antenna numbers
Transmission loss
Unit converters
Attenuators
EMC and Shielding
RF Mixer analyser
DSP
General RF calculators
Butterworth filters
Impedance matching
Interdigital filter calculator

73, Onno PA3AKP

Read more – Southgate Amateur Radio News RSS Feed http://www.southgatearc.org/news/2022/august/free-windows-rf-calculator.htm
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