My HF Rig and Antenna

HF station overview.

Overview
Click on the picture to get an overview of my HF station and antenna.

Kenwood TS-850 transceiver.

HF transceiver
My HF rig is the Kenwood TS-850S multimode transceiver. Receiving range is 100 kHz - 30 MHz. Transmit ranges are the ham bands from 1.8 MHz to 30 MHz. The transceiver is powered by a Kenwood PS-52.

This transceiver offers a multitude of features like all-band all-mode operation, digital read-out, dual VFOs, RIT/XIT, split mode, full break-in on CW, notch filter, AGC off/fast/mid/slow, noise blanker, tone control, DSP filter, speech processor, monitoring of transmit signal on SSB/FSK, VOX, and all-mode squelch. Computer aided tuning is also available. Certainly, you can do without these features, but they are worthwhile additions and will increase your operating pleasure.

The TS-850S has an accurate output meter. The RF level can easily be reduced to 5W QRP.

Balun and automatic antenna tuner.

ATU
An automatic antenna tuner (SG-239 from SGC) is housed inside a weather-proof box and placed close to the feed-point of the loop antenna. Power (12 V DC) for the ATU is provided via the coax cable. I use a bias-tee at the radio and at the ATU.

A broadband balun (BL2 from Elecraft) is placed between the tuner and the antenna. It is housed inside the plastic box. The balanced side of the balun is connected to the loop antenna. The balun has two impedance options (1:1 or 1:4). I've selected the 1:4 option.

When the operating frequency is changed (or when the antenna characteristics change), the antenna tuner requires RF from the transceiver in order to realign for lowest SWR. A few seconds of carrier at 5 W is usually enough for this task.

Loop skywire antenna.

Antenna
My loop skywire antenna is 43 meters long and erected horizontally. The loop is supported in 4 corners and the feed-line is connected in one corner. The antenna resonates in the 40 meter band but is usable on the higher bands as well. The ATU secures impedance matching with the transceiver at all times.

The loop itself is made of 1 mm enameled copper wire. The 4 insulators are made of makrolon (high tech polycarbonate) and they are connected to the support points using black 1.5 mm Dyneema rope. Insulators and rope were purchased at www.dx-wire.com

Latest revision: July 27th, 2010 by Lars Petersen, OZ1BXM.

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