Dipole calculator

In the next few days, I have to make a dipole for the 8m band on which I have special permission to TX for 12 months. At my QTH, the most suitable antenna is a simple wire dipole. You may be interested in this calculator.

See https://www.wireantennas.co.uk/dipole-calculator . 

External 10m dipole

A week early, the coax for the feed to my 10m dipole has arrived. 

Assuming my son can help next week, I have all I need to get this up externally. It should be several dBs better than the indoor loop I am using presently.

External 10m antenna

Small steps....

• The first stage was to drill a hole for the coax into the shack.  This needed a long masonry drill bit, which I had. It turned out to be far less difficult than I was expecting. DONE.
• The next stage, which will need help from my son, will be erecting the wire dipole. Both supports will need ladder work, which I can no longer do. If I attempt it I am likely to be giddy. This involves cutting the dipole wire to the correct length and running the coax into the shack.
• The final part will be attaching the BNC plug and testing the antenna.

But, I do not have coax! I thought I had a reel, but will have to buy some. I guess I need about 5-6m, so 30m from Amazon should be fine.

10m dipole

One of the simplest antennas is the dipole made of wire. 

On 10m this is quite small being only about 5m long. Although I have been very impressed with my tiny indoor loops, an outside dipole should be several dBs better in the best directions.

Whereas, in the past, erecting this would have been a trivial task, my ladder days are largely over, so I depend on others now for erection. Hopefully my son can help in the coming weeks. 

It would be good to have this up before the Es season starts, late next month. By the autumn I think we can expect the USA to come through regularly on 10m, even on 10m AM just above 29MHz.

I have an idea on where to hang it. This should be good for North America and Europe.

10m antennas

As you will have noticed by now, 10m is one of my favourite bands.  Although quiet at many times in the solar cycle it always comes to life with Es from late April until September. Alert 10m operators will sniff out Es at other times too, but there may be long periods of noise, as on 6m. WSPR is an ideal mode when the band may otherwise seem quiet.  It is good for local nattering at any time and F2 N-S DX  is often there even at solar minima.  Antennas for the band are small and easy to make such as the design on my website for a 10m halo. See https://sites.google.com/site/g3xbmqrp3/ .

A video of K7AGE making a dipole for 10m is available at YouTube.  See https://youtu.be/84F4UgSWmQo.   In this video, Randy is making a dipole for the USA technician's band, so to cover the main SSB band (28.4 to 28.6MHz) you will need to make the wire slightly shorter.  In my experience if you cut the wires for the centre of the band it will still have a pretty low SWR at the band edges. Even a very simple ATU will bring the SWR down to 1:1, although  unless your rig has a problem with a mismatch of around 1.8:1, I would not bother, as the difference in radiated power is negligible (fraction of an S-point).

Because of the short wavelength, 10m antennas don't have to be that high to be effective. When the band is in good shape, worldwide DX can be had with simple wire antennas and low power. It is a rewarding band.  What is more, 10m multi-mode transceivers can be bought at low cost.  In summary, 10m is unique: low cost transceivers, simple antennas and good DX potential.