Review on Balun One Nine v2 Barebones: Affordable 9:1 HF Antenna Balun and Unun for Shortwave with Input Protection, Ideal for RTL-SDR, Ham It Up & SDRPlay by William Groupp

"Random Wire" antenna, expects to be able to be configured as an autotransformer like V1. The device I bought could not be configured like this - the RF transformer on the board is different. (The HF transformer isn't center-tapped like the V1 transformer.) However, you can probably use this to match a balanced and unbalanced line, which my testing seems to confirm - it's just not "typical". unun setup autotransformer commonly used. When I brought this to the attention of Nooelec they took a little time to look at this and get back to me but they look at what impressed me and decided to refund my purchase (which was way higher and higher and not necessary, but still very valuable.