Today, Wednesday March 28th, Jaap PA7DA did start to build the Deltaloop antenna for 6 meters. As a interested radioamateur to operate on 6 meters it will be nice to work with a simple antenna for 6 meters. The first plans are to use the shortened G5RV antenna wich also can be used for 6 meters. But a Deltaloop will be better and is also simple and easy to transport during the journey from Holland to Israel in the normal package.
First by reading the Rothammel Antennebuch it was easy to find the good information and the information on the webpage of DL5DBM made it complete clear. The antenna is easy to build. But Jaap will take all the time. The construction must be strong and we don't like problems during operating in 4X.
During the construction and testing Jaap PA7DA will give information about this 6 Meter Deltaloop.
On the picture the parts of the Deltaloop, Like the RG59, the insulated 1,5 mm copper wire, isolators made of plexiglass and some another stuff for fixing the parts.
According the results of W6DL in 1967 the total length, in meters, off the wire must be 306,6/f. For 6 meters it is about 6,11 meters. The impedance will be 110 Ohm. By fxing a turned RG59, 75 Ohm coax of about 1 meter the total impedance will make it 50 Ohms and also easy to use by all the 50 Ohm cabels like Rg58 and 213.
Update March 31st 2012
Friday afternoon March 30th during my lunchbreak I did start to fix the Deltaloop just outside the laboratory of my QRL at the Delft University. The situation was to low and fixed between a metal fence and the concrete building. So not a good situation for a measurement on a antenna! Or because of the bad situation a good location?
With some nylon ropes I fixed the antenna and connected (BNC-connector) on the 50 Ohms RG58. Between the antenna and the RG58 the “Choke” made of about 1 meter 75 Ohms RG59.
At the another site I connected the cable on the MFJ-259B antenna analyser and surprized that the results are acceptable. SWR 1,5 and the impedance 43 Ohms.
I think as when the antenna will be fixed on free and higher area, the results will be better.
But the FT897D is also connected with the LDG-AT897Plus and will tune the antenna better as needed. Still I am satisfied about this results.
The polarisation of this antenna is depend on the feeding-point. In the picture here below the reader can see several description’s about this antenna. The idea came from a story in VERON’s Electron in April 2006 from Peter PA0PEV. Only his construction is different with the horizontal part down and fixed on a PVC-pipe because the feeding-point is halfway this horizontal part.
On internet I found a saved webpage from Peter Halpin SK PH1PH/PE1MHO with a better construction, hold and fixed with 3 ropes. The horizontal part is upstairs and the feeding-point in de top down point. The final description I found on the webpage of DL5DBM.
The choice to build a Deltaloop is only that during transportation from Holland to Israel is a weight problem. We have to transport also our daily needs, like our clothing and also the equipment. Indeed a good antenna is very important. But to work with a simple wire-antenna like a shortened G5RV is for 6 meters can be better. The Deltaloop can be fold and packed very easily.