Review by Julian G4ILO...
I have had a Wonder Wand Combo for a few days, trying it indoors using an FT-817 barefoot. It is quite difficult to get contacts and reports due to the "CQ DX" phenomenon which means that the stations with big signals making quick contacts aren't interested in working a weak G.
You can spend a long time waiting for someone happy to chat to finish a QSO, then either he goes back to someone else or goes QRT!
So far I have made two contacts on HF using SSB: a Spanish station working pileup style on 15m who gave me 59 (!) and a Swede on 17m who gave me 43 (and a new IOTA!)
Working QRP SSB is hard at the best of times and so I don't think these results are too bad. I tried some rough A/B comparisons on 20m with my loop antenna which is roughly comparable to a dipole and the difference on the WW was less than switching out the preamp on my K2, so I suppose 6 to 8db down on the dipole.
Having pre-set switch positions for each band makes for very convenient band changing. The WW seems optimised for use without a counterpoise. I found that the counterpoise makes little difference to the received signal strength, but it does provide an easy way to tune out any residual SWR. There is no need to play with the length of the whip antenna, as long as the WW is attached directly to the back of the radio.
When I tried to get some more precise accurate SWR measurements by attaching the antenna to an SWR meter connected to the 817 by a small patch lead, I got high SWRs that were at complete variance to those observed on the 817. I supported the WW so I could attach it directly to the back of my K2, which has a built in digital SWR readout, and confirmed that low SWRs are achievable using just the WW and counterpoise controls, without shortening the whip, but only with the antenna connected directly to the back of the radio.
The use of even a short 50cm patch lead somehow upsets the tuning.
Considerable reduction of the whip length, or even using the 15m band position for 17m, is necessary to get a good match.
I also get the impression that grounding the radio can affect the WW tuning. Because the FT-817 has a ferrite on the power supply cable it doesn't provide a good RF ground through the power supply. I had to disconnect the K2 from everything and run it from its internal battery to get the best results.
One thing that is not mentioned in the instructions (if they can be called that) is that the WW works very well as a 3/4 wave on 2m. No need to shorten it to 19 inches. The match is perfect, the counterpoise makes no difference, and I received the strongest signals I've ever heard from here on 2m (due to very low activity on VHF/UHF I don't have any permanent antenna on those bands to make a comparison with.)
I was unable to find the setting to give a good match on 70cm. This is no big disadvantage from here, as I have never, ever heard anything on 70cm at all, but it would be nice to know the magic setting for use elsewhere where there may be 70cm repeaters I could use.
It would be very interesting to see how the dipole version performs. However, I think it might work better for apartment dwellers who are able to give it the benefit of some height. I chose the vertical version because I wanted something that might work fairly well on the beach, where there is nothing convenient to support a random wire, though the weather here now is unlikely to encourage testing that until next year!
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