I constructed and used a NorCal Sierra QRP rig for Field Day 1998. This rig was designed and tested by members of the NorCal QRP Club. A construction article for the Sierra has been included in recent ARRL Handbooks, and a kit for the rig is offered by Wilderness Radio. (The Wilderness Radio version of the kit contains a few improvements over the radio described in the ARRL Handbook.)
The Sierra is a 3W transceiver that will operate on any of the HF bands with the appropriate band modules. These modules are small daughter boards that contain a crystal and some tuned circuits for various stages of the rig. Bandswitching is performed by the removal of the current band module and insertion of another band module. This operation takes seconds. The rig was designed for low battery consumption applications like backpacking. The receive current draw is about 30 ma. and the transmit current draw is about 450 ma. For specifications on the Sierra, see the Wilderness Radio Sierra page.
I was very impressed with the Wilderness Radio version of the radio. It came with a detailed construction manual, a well done main printed-circuit board, a professionally produced chassis, and three band modules for 40M, 15M, and 12M. (Note that you can order the kit with just the band modules you need.) To my surprise, the kit even included magnet wire for winding the torrids. (There are 8 torrids per band module and about 5 (if I recall correctly) on the main board.)
The manual for the Sierra is reminiscent of the old HeathKit manuals; however, the Wilderness Radio manual doesn't hold your hand as much as HeathKit manuals did. This is not a first kit: The circuit contains 9 ICs and several transistors and requires the winding of a number of torrids. Experienced builders will love this kit, but those new to kit building and electronics may have trouble. The manual gives three alignment procedures: one using a DMM RF probe, one using a general coverage receiver and a ham band transmitter, and one using real test equipment. Another nice feature of the manual is that it gives details on some typical customizations.
All of the jacks, switches, variable capacitors, and potentiometer are mounted on the PC board, so there is no off-board wiring for these. The chassis contains an easy-to-remove top that makes band module switching an easy operation.
I worked on the kit about a week and a half, working one or two hours a night on weekdays and a little more on weekends. I finished the rig the day of Field Day 1998, did a quick alignment, and put it on the air while the solder was still a little warm. It worked first time! The features of the rig make it a nice rig to operate. It includes RIT and fast QSK.
The chassis has plenty of room for options. Wilderness Radio sells a combination LCD frequency counter, keyer, S-Meter, and wattmeter. They have an optional front panel for the display and switches of the KC2 that replaces the Sierra front panel.
I hurriedly wrote this review. There are lots of details you can get from the ARRL Handbook or Wilderness Radio home page that I didn't address. But, to summarize my thoughts, this is an awesome kit, both the design and Wilderness Radio implementation.
For pictures and prose about my use of the Sierra during field day, see my Field Day '98 page.