Part of our FT-891: The Complete Guide.
The FT-891 is my go-to for a full 100W field kit, and what I actually pack changes depending on whether the Jeep is part of the trip or I’m hiking in on foot.
When the Jeep is involved: the ATAS-120A
If I’m driving to a POTA site and operating from or near the Jeep, the ATAS-120A stays mounted and does the job, it’s already tuned to the vehicle’s ground plane and I don’t have to deploy anything separate. This is the fastest setup I run, park, key up, activate, since the antenna and radio are both already in place from the regular mobile install (see my YSK-891 separation kit install for how that’s wired up).
When I’m away from the Jeep: Spooltenna or the CaHR Hydra
For a SOTA hike or any activation where the vehicle isn’t part of the picture, the ATAS-120A’s mobile ground plane setup doesn’t apply, so I bring either the Spooltenna Ultra or the CaHR Hydra. With the Hydra, I usually run it as a horizontal dipole with the 17 foot whips, it packs down small, deploys fast, and performs well without needing a mast if the site doesn’t have good trees.
The rest of the kit
The MFJ-939 rides along whenever I’m not on the ATAS-120A, since neither the Spooltenna nor the Hydra dipole configuration gives me a guaranteed resonant match on every band. Power comes from the LiFePO4 box on foot activations, or straight off the Jeep’s electrical system when the vehicle’s part of the trip. Logging is paper as backup no matter what, plus a phone app or laptop depending on how much I’m carrying that day.
The full checklist
- FT-891 and control head, plus the YSK-891 cable if running separated.
- ATAS-120A if the Jeep is part of the trip, otherwise the Spooltenna Ultra or CaHR Hydra with 17 foot whips.
- MFJ-939 with the Yaesu adapter cable for any non-ATAS antenna.
- LiFePO4 box and properly fused power cable for foot activations.
- Paper log, pencil, and a callsign and grid square cheat sheet.
- Water, sunscreen, and layers appropriate for the actual site.
Why the split makes sense
The ATAS-120A is genuinely the fastest option, but it’s tied to the vehicle’s ground plane, it’s not something I’d carry on a hike. The Spooltenna and Hydra fill the gap for anywhere the Jeep isn’t part of the operation, and having both options means terrain and access decide the antenna, not the other way around.