[MRCA] 60 Meter portable operation questions

[MICHAEL ST ANGELO]

I've enjoyed the discussion on the 60 meter portable antenna. Let me summarize.


Al and others recommended an end-fed half-wave resonant antenna. Since Breck had to feed at the base of the mast this is the route he took.


Advantages are you don't require a long transmission line. The disadvantages are you need a counterpoise and you have to watch the losses in a matching circuit matching such a high impedance transformation about 5000 ohms to 50 ohms.


Mindful of the losses in a matching network Ray recommended a center-fed half-wave inverted V fed by transmission line. Since the impedance is low a matching network is not needed. I counterpoise in not necessary.


Someone else recommended an end-fed 5/8 wavelength antenna. The impedance is lower and is easier to match.


My telescoping pole is a fiberglass Jacktite pole which can go up to 30 feet but cannot support a heavy load. Al suggested a lower height is suitable for NVIS. The Jacktite pole is supported by a tripod.


I will first try a half-wave center-fed inverted V fed with RG-58 since that is the easiest to build. I will see how my pole supports the load.


I'll then try a half-wave end-fed V with a matching network. I will try Breck's matching network or a L or PI network to match the load and put down a couple of counterpoises.


I probably will not wait until spring but end up doing this during the coldest weekend of the year. It seems do antenna work in the winter.


Mike N2MS



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