Antenna 9:1 impedance transformer for the RTL-SDR to connect long wire 100k - 50Mhz (BALUN)
Copy of Balun 9:1
Construction of a 9-1 unun - YouTube
Amazon.com: Balun One Nine v2 - Small Low-Cost 9:1 (1:9) Balun with Input Protection & Enclosure for HF & Shortwave. Great for Software Defined Radio (RTL-SDR & SDRPlay), Ham It Up, and
1:1, 9:1, 49:1 Matching Units - What's the difference? - YouTube
9:1 UNUN | eBay
9:1 Magnetic Longwire Balun / Unun – M0UKD – Amateur Radio Blog