10/80 meters dipole Portable
 

When you think of building an antenna, usually it is done because after also trying to assemble and use.
If you are using, then, the / P, you should also try to think of different situations that logistics may from time to time.
When I started, just to try and go out on handset to activate the castles Italian, I used a dipole (always DIY!) supported by a rod 6 mt long and, as a base of support, a military base recovered in a garage sale years ago that houses a diameter of 50 mm.
The problem was, of course, the lack of convenience and speed of installation with the consequence of not being able use this antenna if not in suitable areas.
Now, after various adventures, I had come to build a vertical viewable on this site, you can install in less than 10 minutes and secured to the car's luggage rack (Fiat Panda 900) 10/40 (80) mt.
This allowed me to go into the intricacies citizens without problems of any nature, for what concerns installation, but with major problems as regards their use.
In practice, a vertical line to connect Italy in the 40 meters, is not the best.
Then we must return to the dipole or, at least, to an antenna installation without major problems of invasion field.
Physically, I'll tell you, the antenna is a classic quarter-wave, because the problems of physical length there are, but the unusual thing is that I just used an attack similar to the luggage rack which I combined with a vertical telescopic mast (the one that used all through Saturday, to remove the cobwebs, when you help the wife in the house to clean!) so as to reach the total height of 7 meters from the ground.
And when you raise the pole, the dipole is at the center of the car!

The traps: this is the part that I have experienced using an donatomi from a friend. I wanted to know how and to what extent the results obtained by the program correspond to reality.

I state that traps, whether in coaxial cable with ceramic condenser coil, all work the same way: they just block the unwanted frequency.

In this case, my trap is a coil with 47 pF capacitor polyester. The coil is composed of 18 turns (but you add a loop more) at diam. 60 mm. Once calibrated the 40 meters, add the trap and give resonance to the 40 meters at a time by removing 4 cm from the wire coil.

Remember that the trap should resonate exactly at the frequency that you sounded the part of the 40 mt.

Now all that remains is to add the case of wire for 80 meters. A accordatina fast, and you will then have achieved the antenna in question. From tests carried out in TX, I say right away that you have to be greatly favored the development, to be heard on 80 meters, but however confirmed that the antenna works perfectly and the car does not create any obstacle to the performance thereof. I've got to be spoken as a portable antenna, but nothing prohibits their use as antenna QRA. Now I move on to the laptop always follow both antennas, both vertical and horizontal, so that they can exploit the best conditions every time you get logistics in place to do business. I know that I have not discovered anything new and that the dipole is treated in all the sauces imaginable, but you have never seen one like this installed?

Good job to those who start work to implement the antenna in question and, of course, good DX! 73 de IK4DCS

ANTENNA