Wimo HF mini dipole for 20m

During my autumn holidays, I didn’t have time to play with the IC-7000 but did some experimenting with my two portable dipoles that I once bought but never used. The first one I tested, was a Wimo HF mini dipole. A pair of 1/4 wave radiators cost about €50 up to €70 and the R1 straight dipole center puts you back another €15. I ordered the 20m versie and paid around €65 for a single band dipole. Not very expensive, especially when you look at Buddipole prcies, but also not a bargain. Here’s link to the “Wimo portable HF antennes”, search on this page for “HF mini dipoles”:


The dipole elements are made of 12mm aluminium tubing, the normal type you buy at your local hardware store. At 1m, there’s a black nylon tube where the end rod (10mm aluminium tubing) is inserted and it’s length can be adjusted. The elements are “base loaded” meaning there’s a big coil (around 5 uH) near the feading point. The coil is wound on a carton (…) insulator with 3/8″ thread and the 12mm tubing. To be honest; it doesn’t look very professional, more like a good homebrew project.

One of the elements has a yellow marker, the (brief) manual explains this yellow marker needs to be screwed in the hot (+) end of the dipole insulator. While base loaded dipoles tend to have a low impedance, I reckon both coils are not the same, but e.g. on has 4 uH and one has 6 uH in order to find a higher impedance (closer to 50 Ohms).

Does it work? I can be short here: No, it doesn’t! Even though there is resonance and a slight dip in SWR, the impedance is way to low on my 5m portable aluminium pole. MMANA calculates almost 4 dB loss compared to a full dipole and about 12 Ohms impedance. With the knowledge that I have right now (I bought these some years ago), even if you’re limited in space, I would not consider buying this system. It might work better on a roof and it’s not a dummy on a stick but there’s just so many better alternatives probably for less many that I would not recommend this sytem.


Geef een reactie

Vul je gegevens in of klik op een icoon om in te loggen.

WordPress.com logo

Je reageert onder je WordPress.com account. Log uit /  Bijwerken )

Google+ photo

Je reageert onder je Google+ account. Log uit /  Bijwerken )


Je reageert onder je Twitter account. Log uit /  Bijwerken )

Facebook foto

Je reageert onder je Facebook account. Log uit /  Bijwerken )

Verbinden met %s