Portable HF Rig and Antenna

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. It is manufactured by Wilderness Radio in California.
The Sierra comes as a kit with one main circuit board and 213 parts. All controls and connectors are soldered directly onto the main PCB.
Besides the standard knobs on the front, I have added an ABX-control (variable filter bandwidth) and a drive control.
I am using the DL-QRP-PA amplifier to obtain 4-5 W output. The power amplifier is mounted on the rear panel.
One band module is required per band. I have built band modules for 40, 30, 20, 17 and 15 meters.

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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