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Cable terminations various
I agree with John G4SWX and would add that the quality of many currently available cables and terminations has declined .
I have found many examples of inter-series adaptors with poor assembly design , where the "crimped" halves are barely retained as purchased and fall apart in real time uses .
When then examined the retaining "crimp" areas are minimal - attempts at salvage involving a heat process are doomed as the quality of the dielectric material is also "value Engineered" and will ooze readily .
Amateur termination of Heliax type cables , using original quality N types , is perfectly feasible to at least 10GHZ , provided that first principles are paid attention to . i.e. impedance bumps are controlled by design of the inner coupling and the back nut is soldered to the outer cable jacket - right up to the mating face .A strong suck out loss will occur at specific frequencies due to resonant length if not - been there found out the hard way .....
I will not even start on issues with Waveguides used in Microwave EME.