TL;DR What does a 70cm VNA trace look like?
Howdy y'all, The car is in the shop, so I had some time on my hands... I took a 16 cm section of 450 Ohm ladder line, shorted one end, soldered on a 32.5 cm length of wire and BOOM. I have another J Pole. I tacked on a short length of RG-8x, 1.6 cm from the end, and put a female BNC on the end. Closer still! I calibrated my NanoVNA for 420-450 MHz and made a trace of SWR and Resistance. I am looking to hit the 444.3 repeater. [image: Screenshot 2025-10-15 at 4.16.08 PM.png] This here is some messed up stuff. Do I have to tune to catch 50 Ohms as it goes by? The SWR minimum is to the left of 444.3, so my J Pole is long. I am about to nibble away. Should I expect a 25 MHz cycle like this? The middle of the cycle will be crazy SWR and terrible resistance, right? Comments welcome! 73 Dan KJ5IZK
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