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Performance: The actual performance from the small package will surprise you. It really tunes a lot
of antennas to a lot of places! Here are some of the actual test results.
A 40-meter dipole (at 30 feet) would tune just about anywhere from 3.1 to 30 MHz! We had some
problems at 19 and 28 MHz finding a 1.5 match. The Z11 usually found a 2.0, and then we had to
use the manual switches to get below 1.5.
Next, an Antron-99 (at 40 feet) would again tune just about anywhere from 30 to 5 MHz. The auto
mode worked great the whole time. We just dialed down the band and the Z11 would kick in
whenever the SWR went over 3.0.
Then we tried out the unit on a 3-element tri-band (20,15,10) at 70 feet. It would tune any of the
ham bands (including WARC) except 160 and 80. We had some problems finding a match around
27.200 MHz, but got around it by moving to 27.000, letting the Z11 find a match, then moving back
to 27.200.
The 80-meter inverted Vee was next. It tuned everything from 3.1 to 30 MHz. We were hoping that
it would tune all of 160 meters, but it only found good matches from 1.900 to 1.800 MHz.
We've tried many other antennas with similar good results. There may be a place or two that your
antenna (dipole, inverted-Vee, vertical, beam, etc.) won't tune. Also, the farther away from
resonance you try to tune, the harder time the tuner will have. The Z11 will tune a 10 meter vertical
to 80 meters, but your performance will not be that great (you can't get something for nothing).
For balanced lines and random wires, you may get better performance by using a 4 to 1 or 6 to 1
balun between the antenna and tuner.
We used the Autek RF-1 analyzer to give us more information about how well the Z11 was working.
We found that it would consistently tune impedances from about 6 ohms to about 850 ohms. This
corresponds to an SWR of about 10:1.
The SWR bandwidth (usable bandwidth of 1.5 SWR without retuning) averaged about 200 kHz. On
the lower frequencies it was smaller (about 75 kHz on 80 meters) and on the higher frequencies it
was larger (about 400 kHz on 10), no surprises here.
Tech Support: Telephone technical support at 410-586-2177 is available most days from 8 am to
9pm Eastern Standard Time. Replies by FAX (410-586-8475) are welcome; e-mail
(ldg@ldgelectronics.com) is also answered on a daily basis.
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