Miracle Whip Antenna Review

The Yaesu FT817 is one of the smallest MF/HF/VHF/UHF multimode general-coverage ham radios. This pocket radio was released in 2001 with the upgraded FT817ND was launched in 2004.

yaesu 817.jpg

It brought the ability to operate portable from any location with its self-contained battery pack (a weakness as they were 1000maH AAs which meant a 15 minute lifespan) and a shoulder strap. The provided rubber antenna covered 6m to 70cm but not HF. As many owners can tell you it’s a superb radio and because of this it’s still in the Yaesu catalog. I understand over a million radios were sold.

What changed everything for the QRP portable operator was when I came across the “Miracle Whip” antenna around the spring of 2001.

mw4

Robert Victor VE2ERY (now an SK) designed the antenna as a companion to his FT-817. This design was also published in the QST July 2001 issue. He also published 2 more articles of interest. Robert professionally hand crafted these antennas from Montreal, Quebec

JUL 2001 – QST (PG. 32)       The Miracle Whip: A Multiband QRP Antenna

JUL 1998 – QST (PG. 56)       The Clothesline Antenna

OCT 1998 – QST (PG. 66)      Welcome to Rentsville, DX

The antenna is a marvelous feat of engineering with a compact box with the tuner and PL-259 connector housed in a compact box with its 1.2 meter telescopic antenna. All contacts are gold plated and it’s rated at 5w.

It is a switched RF autotransformer with 45 taps acting as the primary winding that steps up the impedance to 50 ohms (very short antennas have a low impedance down to as low as 2 ohms). Apparently a counterpoise is not recommended but I find it works better with a 10 foot length of wire clipped to the ground lug on the 817.

For HF, one tunes the radio for strongest receive signal and then can adjust the swr usually a click up or down and using the built in SWR meter on the 817 makes getting on the air easy.

SWR figures are typically under 2:1 and 80m of course is a problem. The antenna is just too short. Its operation is typical of a short base loaded mobile antenna.

I made lots of contacts on 20m and 17m with this miracle antenna. The antenna can also be used on VHF and UHF with a position that adds very little inductance and you adjust SWR by telescoping the antenna length.

For general SWL listening out on the back deck the antenna is a charm as it’s quick and easy to tune for best signal and listen away. I have experimented by adding a clipped on wire to it and it does seem to improve its operation.

Tap 3 tunes 80m, Tap 17 tunes 40m, Tap 24 tunes 30m, Tap 29 tunes 20m, Tap 33 tunes 17m, 15m is Tap 38.

For the portable SWL operator obviously the major broadcast bands are in between the taps.

In 2002 , Yahoo “HF-Pack” Group the Miracel Whip  was compared with a variety of other antennas in controlled conditions on an antenna test range. Its gain without a wire counterpoise was measured as 10dB below a reference vertical on 20m (16.5′) . Other antennas that were more than twice as long like PAC-12 (9.5′)  faired much better being a few dB down. This isn’t too bad for an antenna that is about 4 feet long and when the band is open you will make contacts.

This antenna is no longer being made in Canada but versions of it are now under the Wonder Wand antenna in the UK.

Here is some data points for analysis or for experimental purposes.

mw data

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3 comments

  1. Mike Hohmann · March 8

    I’ll be looking into this. Thanks! de Mike, KEØGZT

    Like

  2. ve3ips · March 9

    Mike, the original can be found used and the alternates can be found in the UK. Try the yahoo group too

    Liked by 1 person

  3. Dale Parfitt · March 11

    I am having difficulty understanding the capacitance graph. Is this the capacitive reactance of the whip by itself?
    Tnx,
    Dale W4OP

    Yes. Someone took the time to measure this

    Like

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