After 18 months with a Hex Beam, I'm transitioning to a traditional aluminum Yagi design. While the Hex Beam performed excellently (took my 12M DXCC from 42 to 187 entities), the wire-to-spreader connections eventually failed in wind storms.

I'm now building a 6-element interlaced design covering 10M, 15M, and 20M with no traps. The 20M driven element is center-fed, while the 10M and 15M elements are sleeve-coupled to the 20M radiator - single feedline for all bands. Boom length is 14 feet with elements nested for optimal spacing.

Question for the group: Has anyone experimented with sleeve coupling optimization? I'm finding the coupling distance critical for maintaining proper impedance matching across all three bands. The commercial designs seem to have this dialed in perfectly.

Sleeve coupling is tricky business. The spacing affects not just impedance but also the current distribution on each band. Too tight coupling and you get unwanted interactions between bands. I'd suggest starting 0.05λ away at the highest frequency and adjusting from there.

My SteppIR has similar element interactions and I've found that VSWR bandwidth suffers when the coupling isn't optimized. You might need different coupling distances for each pair of elements to maintain good match across all bands.

The aluminum approach is definitely more robust. I've seen too many wire beams fail mechanically. Your interlaced design should give excellent F/B ratios if you can get the element phasing right. Consider using EZNEC Pro for the optimization - much better than free alternatives for this complex geometry.