My Fixed HF Station

My Fixed HF Antennas

So far, I moved eight (8!) times in my life, although I hope to have settled down now for a while... at my birthplace! «East, west, home's best?»
On almost every location I tried to make the most out of my brief stay, available space, height, antenna restrictions and operating habits. I learned a lot about HF antennas along the way, such as:

• Excellent results (DX!) are possible as long as you choose and optimise your antenna design in function of your given location and surrounding buildings.
• However, for my later relocations I sought to rent lofts that give you «natural» height without the need of a tower, whilst very often being located close to city centres. After all, I have to admit that HAM radio is a hobby that requires a substantial amount of estate and therefore a wad of money.
• Horizontal antennas at a height of about ½λ produce more gain than vertical antennas, due to constructive ground reflections.
• It is a better to have a few good and uncomplicated homemade antennas, that are optimised for your favourite bands and that require little maintenance, than a mediocre commercial antenna with a nest of lossy traps that fails with the first autumn storm.
• Indoor antennas are a valid and safe option as long as your roof is made of ceramic tiles and not shingles which shield off radiation. The high permittivity of the ceramic material in the immediate vicinity of the antenna significantly reduces its resonant length and also slightly its input impedance. Lightning conductors, electric wiring and water pipes may or may not compromise the working of an indoor antenna. All depends of the frequency, the relative conductor length to earth and their interconnections. Only resonant conductors will influence the radiation pattern and on rare occasions the input impedance of an indoor antenna. When modelling the antenna one may include the alien conductors in order to understand their effect. Alternatively, you may just go ahead and try it. Don't let this put you off of having a great indoor antenna!

All antennas are homemade, except for the Rhode & Schwarz and the OptiBeam. Furthermore, all antennas were operated using a sheath-current choke and/or balun, but without making use of an antenna tuner.

used	antenna (Click for more info)	height above ground	power	QTH	call	remarks
1994-1995	W inverted-V dipole with 4 coaxial traps	8m	100W	Oostende	ON4BAA	too low, traps difficult to tune
1994-now	indoor 20m-band dipole	8m	3W	Oostende	ON4(B)AA	100W melted soft-PVC case feet
1995-1996	Rhode & Schwarz dipole with 2 resistive traps	12m	100W	University of Hull	G/ON4BAA	good European coverage
2001-2003	off-center-fed dipole (Windom)	13.5m	1kW	Zaventem apartment	ON4BAA	too low, poor 80m VSWR bandwidth
2001-2003	OptiBeam OB6-3M 3-band Moxon/Yagi beam	13.5m	1kW	Zaventem apartment	ON4BAA	excellent antenna
2003-2005	indoor loaded 40 & 80m-band dipole	17m	1kW on 40m 100W on 80m	Luzern loft	HB9DWU	on 80m: narrow bandwidth and sparking when P > 100W
2005	20m-band dipole	14m	1kW	Luzern	HB9DWU
soon	center-loaded off-center-fed dipole	16.75m	1kW	Hasselt city-centre lot	ON4AA

Yaesu G-800SDX: Antenna Rotor

Yaesu

Idiom Press RotorCard SDX

Click here to learn more about it.

ACOM-1000: 1kW HF Linear Amplifier

Click here to learn more about it.

I bought it here

Yaesu FT-990

160-10m (1.8-30MHz) 100W HF transceiver with built-in power supply, antenna tuner and RF FSP (RF Frequency-Shifted Speech Processor). Optoinal narrow-band filters are installed: 250Hz for CW & digital modes and 2kHz for SSB. Needless to say, Yaesu is my favorite transceiver brand!

I bought this transceiver new in 1994. It was the little brother of the FT-1000 which was considered top-of-the-line at that time. The FT-990 certainly was quite complex for being my first HF transceiver. I learned some very useful lessons with it like setting shift, notch, attenuation, clarifier, speech processor, split, RTTY-tones, etc.. For example: More often than I like, I need to convince fellow contesters about the beneficial effect of adding a little attenuation in front of an overloaded first-stage mixer during a contest night on a overcrowded 40m-band.

I am closely monitoring the most recent developments in the design of amateur HF transceivers. The Elecraft K3 is very tentalising and still affordable. Measured at 102dB, the K3 offers industry's best 2 kHz 3rd-Order Dynamic Range, as well as roofing-filters, RTTY-interfacing and everything else you would expect of a modern transceiver. There is also an option for a second receiver that can monitor a frequency different from the calling frequency during contests. A minor nuisance is the lack of a built-in power supply. So far, I have not succumbed to the temptation of renewing my HF transceiver. I prefer to keep my bucks for the more rewarding but difficult investment in aluminium and stainless steel —i.e. towers and antennas.

Heil Pro Set 4 with Foot Pedal

A very comfortable but somewhat warm headset from Heil Sound that effectively shields your hearing from surrounding noise.

Equipped with the legendary HC-4 microphone cartridge element the microphone achieves excellent DX-ing characteristics thanks to a 500-3800Hz frequency response with a 10dB rise at 2 KHz for better speech intelligibility.