Friday, 29 March 2013

Origin of the EFHWA antenna ?

A while back I was trying to determine the origin of the end fed antenna. Today we use often refer to it as the EFHWA - End Fed Half Wave antenna.

It appears as if this "End feed Dipole" was discovered by Josef Fuchs - OE1JF way back in 1927

The info below I copied from:

There is also some mention of the Zepp antenna published in QST 1928 apparently. It would be great to see the article. Can any one assist?

The Fuchs antenna
die Fuchsantenne wurde im Jahre 1927 vom österreichischen Funkamateur Josef Fuchs, OE1JF, propagiert und auch patentiert. Es handelt sich um eine Langdrahtantenne, l=41,7m, die ursprünglich induktiv über einen Schwingkreis (den Fuchskreis) an den PA-Kreis des Senders angekoppelt war (Spannungskopplung).

Fuchs antenna as patented in 1928
Bei heutigen Transceivern mit 50-Ohm-Ausgang TRX wird der Fuchskreis am Ende der Antenne angebracht und über ein Koaxialkabel gespeist. Aufgrund der Bauart der Fuchsantenne treten im Fuchskreis auch bei kleineren Leistungen hohe Ströme auf, die Folge davon ist im Regelfall (sagt man, diese Begründung ist aber nicht einleuchtend!) ein Auftreten von Störungen TVI. Durch die Spannungskopplung arbeitet die Fuchsantenne scheinbar gegengewichtsfrei. Der 41,7m lange Langdraht kann auf allen geradzahligen Harmonischen von 80m qrv werden, es ist eine Multibandantenne; allerdings muß der Fuchskreis dazu umgeschaltet werden. 

Frank Lamprecht, DL7AQT

Friday, 15 March 2013

Ticking boxes….

Yesterday I noticed that the foF2 was looking very promising and I had a pretty good feeling that this would result in exceptional 6m propagation not only in the normal TEP window, but possibly even into Asia, Far East and the Middle East before that.

Well I was wrong. Nothing spectacular happened. In fact the conditions were pretty poor. However I was very aware of the fact that Diya Z81D in the Southern Sudan was now also active on 6m. Sudan lies only slightly north of the equator and TEP would not be possible, the solar numbers don’t look all that good so a F2 opening was unlikely.

Diya appeared on the ON4KST cluster and I immediately asked him to turn his beam south. He did, but we heard nothing so he turned north again and he worked a few Europeans. I remained on the frequency and low and behold about an hour later I heard his signal briefly, just above the white noise.

The rest is history…. Z81D Southern Sudan’s DXCC box can now be ticked as worked.

The 6m band hold many surprises, no wonder it is often referred to as the Magic Band.

54 down, 46 to go....

foF2 14 March 2013 07:00 Z

Friday, 8 March 2013

Conundrum – When to call, when not to call

The DX stations will often use directional calls, to manage the pile-up. They will normally call “Europe only”, “North America only” or “Asia only”

This is all fine and well if you are located in EU, NA or AS, but if you are located in Africa (AF), Middle East (ME) or Oceana (OC) you have a problem.

The expeditions very seldom (if ever) call all the continents in turn. They switch between the big three NA, EU and AS all the time.

So where does it leave the rest of the amateurs that are not located in the big three?

Do we ignore the directional call and call regardless? If we do we stand the risk of being totally ignored or even worse being black listed.


It would be better if the DX expeditions used something along the lines of “Europe and North America standby” meaning all others call now. In CW that would be “EU NA QRX”

That would be a far better solution?