...aaaand, the best I can muster is this: [image: Screenshot 2025-10-15 at 5.19.18 PM.png]
Very strange. I moved the feed point to get a lower impedance and trimmed the driven element quite a bit, but can't get it to come down at 444.3 MH. At this rate, I am going to stick with 2 meters! Dan KJ5IZK On Wed, Oct 15, 2025 at 4:20 PM Daniel Poirot <[email protected]> wrote: > 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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