Thursday, 29 January 2009

Multi-band loft-mounted dipoles for 40, 20, 17, 15, and 10m


Amateurs are always after the Holy Grail - an antenna that will work on all bands, is inconspicuous, effective, but above all inexpensive. Unfortunately, you seldom find something that fits all these factors.

This antenna has nothing new about its design, but it does bring together quite a few useful ideas and characteristics.

These are:

• Fully no-tune antenna system for five popular HF bands

• Suitable for SWLS, QRP, M3 licensees and PSK31 operating plus occasional useup to 100W, but watch out for RFI at high powers. DO NOT USE A LINEAR!

• Uses non-inductive (zig-zag) loading for 40m

• Feed point balun reduces RF pick-up and interference making it quiet.

2 comments:

  1. Another interesting idea. My approach to HF operation in an attic that looks about the same size as yours is to use the G3OJV 80plus2 design from Waters and Stanton. It is a full-size dipole on 20m, linear loaded on 40m, and end loaded on 80m. I plan to add extra elements for 15m and 10m later, when propagation makes those bands actually useful. The bandwidth is pretty narrow on 80m and performance is quite a bit worse than a full size dipole, but if you know of a better solution suitable for an attic that size please let me know!

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    Replies
    1. Using a Carolina Window 40-10m in the loft works great, especially on 40m.

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