On 12/18/21 8:19 AM, JF1XCV wrote:
Hi All!
I am now evaluating a 1:6 UNUN with NanoVNA that I bought quite recently. The UNUN is made of two stacked FT240-61 and 1.6mm copper wire with 100pF capacitor in the primary. To measure SWR, a 1800 ohm carbon resistor is soldered in the secondary side. To my surprise, SWR is 1.0 from 1.9MHz to 430MHz. I suspect I misunderstood how to measure SWR with NanoVNA. I am attaching the screen of NanoVNA Saver. Any comments are welcome. Thank you.
You have a transformer with 36:1 impedance ratio, and an 1800 ohm load.? You should see 50 ohms on the other side. That is pretty close to what you see.? What were you expecting?
