Little Tamarack Mountain (W7O/NE-137) makes a nice activation destination in north-central Oregon as it's located in the Umatilla NF near a Forest Service rental cabin/lookout with two other summits nearby, including Ng Knob-4820 (W7O/NE-147) and Happy Jack Ridge (W7O/NE-139).  I rented the cabin for two nights.  Activated Little Tamarack on the first day, then bagged the other two summits the next. 

Little Tamarack requires a short hike of about 1/2-mile with approx. 400’ gain.  There's an ATV road you can follow to start, but much of the hike is crosscountry with some light bushwacking. 

The summit is forested and brushy (see pics), but has a sizable AZ with trees that will support wires, etc. 

Info on the rental cabin is here:  https://www.fs.usda.gov/recarea/umatilla/recarea/?recid=56449

Note that the cabin and lookout are on a seperate Taramack Mtn and not the referenced summit.

Directions to the rental cabin and overall area are provided on the linked cabin site.

I had good Verizon cell/data service on the summit, and spotty at the cabin.