I want to sweep my 2 meter antenna from the end of a 15 to 18 foot coax. This is because I need to get the antenna out in the clear away from nearby objects to get a good indication of the actual VSWR. The antenna has an SMA connector. I have two pieces of coax I can use. One is 15' of LMR-100 with SMA connectors on both ends. The other is an 18' piece of RG-8X with PL-259 connectors at both ends. In either case I can move the plane of calibration to the end of the coax where the antenna connects.
So I have two questions for those who have a lot of VNA experience in this group:
1) Since LMR-100 is lossy at 2m frequencies, will I lose much precision in the sweep by calibrating at the end of the coax?
2) Am I better off using RG-8X knowing that I will need to adapt the PL-259 to SMA at both ends? I understand that PL-259 connectors are not so good at VHF and adding adapters will only make them worse.
Which is the better alternative?
Albert KK7XO
