Portable HF Rig and Antenna

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The Sierra CW Transceiver
HF transceiver
My portable HF transceiver is a Sierra CW QRP transceiver. The Sierra is described in the ARRL Handbook 1996 and later issues. Back then, it was manufactured by Wilderness Radio in California. The Sierra is no longer in production.
The Sierra came as a kit with one main circuit board and 213 parts. All controls and connectors were soldered directly onto the main PCB.
Besides the standard knobs on the front, I added an ABX-control (variable filter bandwidth) and a drive control. 
I used the DL-QRP-PA amplifier to obtain 4-5 W output. The power amplifier was mounted on the rear panel. 
One band module is required per band. I've built 5 band modules for 40, 30, 20, 17 and 15 meters. 
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Balanced antenna tuner
Antenna tuner
A balanced antenna tuner is needed for antennas like multiband wire doublet. The homemade unit has three functions:
  • Balanced antenna tuner
  • Dummy load
  • SWR and power measurement (Stockton Power Meter)
A switch on the front selects the appropriate function. The tuner is kept in-line all the time. The antenna tuner is described in detail on my Balanced Antenna Tuner page. 
Center-fed Zepp antenna
Antenna
My portable antenna is a balanced center-fed wire antenna inspired by the chapter A Universal HF antenna system in the book "Simple, low-cost wire Antennas for radio amateurs" by William I. Orr and Stuart D. Cowan (ISBN 0823087077). 
This antenna is sometimes call a center-fed Zepp, sometimes a Doublet. 
L is tip-to-tip measurement of the flat-top. S is the length of the balanced open-wire transmission line. For ease of tuning, L+S should equal one of the four dimension combinations 34.6 m (110') or 40.5 m (133') or 54.0 m (177') or 64.8 m (212').

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