9:1 UN-UN Long Wire Transformer for HF Antennas

9:1 UN-UN Long Wire Transformer for HF Antennas: A detailed guide to the 9:1 UN-UN long wire transformer, explaining its design, connections, grounding, and HF antenna performance.

Most "random wire" antennas aren't actually random—they’re high-impedance headaches. If you’ve ever struggled to get your internal tuner to "bite" on 40m or 80m, you need a 9:1 Unun.

VU3DXR just dropped a deep-dive guide on this essential transformer. It’s not just a wiring diagram; it’s a masterclass in:

• The "Why": How to turn $450\Omega$ into a radio-friendly $50\Omega$.

• The Build: Winding a T-200-2 core for 400W of power handling.

• The Reality Check: A look at actual efficiency losses (and where this antenna shines).

If you do POTA, SOTA, or just love a "stealth" backyard wire, this is a must-read.

🔗 Build yours here: https://vu3dxr.in/91-un-un-long-wire-transformer-for-hf-antennas/

#HamRadio #DIYAntenna #9to1Unun #HomebrewRadio #POTA #SOTA #RadioGeek