RigExpert AA-2000 ZOOM QST Review

Mark J. Wilson, K1RO, [e-mail]

Product Review

RigExpert AA-2000
ZOOM 0.1 – 2000 MHz
Antenna and Cable Analyzer

Reviewed by Phil Salas, AD5X

[e-mail]

The AA-2000 ZOOM is RigExpert’s latest and most
capable antenna analyzer. Like all of the RigExpert
antenna analyzers, the AA-2000 ZOOM is a single-port
vector network analyzer (VNA). It provides signed,
complex impedance measurements of RF loads from
100 kHz to 2 GHz with a frequency resolution of 1 kHz.

Overview

The AA-2000 ZOOM is a bit larger than other ZOOM
models. The measurement port is a Type-N female con­nector, but a UHF-to-N adapter is included for the more
common PL-259 interface used by hams in the HF and
VHF ranges. Also included are the user manual, a USB
cable for computer interfacing, three 2,700 mAh NiMH
AA-size batteries, an external NiMH AA-size battery
charger, a carrying case, and a carrying strap.

You can substitute 1.2 – 3.7 V lithium or alkaline AA
batteries for the NiMH batteries. Depleted NiMH bat­teries take about 6 hours to charge with the included
charger, and a battery indicator on the main menu
shows the battery status. When a computer is con­nected, power is provided though the USB connection
and the battery display is replaced by a USB icon.

Internal memory provides for the storage and recall of
measured parameters in a variety of formats. All infor­mation is displayed on a 2 × 1.5 inch, 800 × 480 pixel
Blanview color TFT-LCD screen, which provides high­contrast, crisp images even in bright sunlight. When the
analyzer is connected to your computer, additional data
recording and analysis capabilities, as well as firmware
updates, are available. Table 1 summarizes the
AA-2000 ZOOM specifications.

Initial Setup

Before using the AA-2000 ZOOM for the first time, visit
the RigExpert website and download and install the
AntScope2 software (Windows, macOS, or Linux

Bottom Line

The AA-2000 ZOOM
is a  exible, accurate
and easy to use
antenna analyzer
for those who need
analyzer capabilities
up to 2 GHz.

versions are available) and the Flash Tool for Windows
or macOS. Connect the AA-2000 ZOOM USB cable to
your computer, which automatically powers on the
AA-2000 ZOOM. Now open the downloaded Flash Tool
file and the Flash Tool will determine if there is newer
firmware available, and — if so — will update the firm­ware automatically. AntScope2 permits importing and
viewing data from the AA-2000 ZOOM’s memory and
provides real-time control of the analyzer.

An Antscope app is available for Android and iOS
devices. The AA-2000 ZOOM has a built-in Bluetooth
feature for communicating with mobile devices.

Table 1
AA-2000 ZOOM Manufacturer’s Specifications

Frequency range: 0.1 to 2,000 MHz with 1 kHz resolution for
25, 50, 75, 100, 150, 200, 300, 450, and 600  systems.

SWR measurement range: 1 to 100 in numerical modes,
1 to 10 in chart modes.

Memories: 250
RF output: Square wave, 0.1 to 2,000 MHz, at –10 dBm into 50 .
Operating temperature: 32 – 104 °F.
Dimensions: 9 × 3.9 × 2 inches. Weight: 15.6 oz. with battery.

Reprinted with permission; copyright ARRL.

www.arrl.org QST February 2022 39

Measurement Capabilities

The AA-2000 ZOOM menus and keypad markings
are self-explanatory, so you will rarely need to refer
to the manual. The user interface is very similar to
other RigExpert ZOOM series analyzers, so if you’ve
used one of these before, the AA-2000 ZOOM will
be very familiar. You can select a single-frequency
display, a swept-frequency display, a Smith chart dis­play, or a time domain reflectometer (TDR) display.

The single-frequency modes let you select displays of
SWR, impedance (Z, R, and X), or the equivalent
series and parallel representation of an impedance.
The MultiSWR display shows the measured SWR on
five different frequencies, making it ideal to look at res­onances on a multiband antenna.

The swept-frequency modes display SWR, return loss,
or impedance (R/X), and all the graphical displays can
be expanded with the ZOOM feature for enhanced
reading accuracy. The ZOOM capability permits you to
scan a wide frequency range, after which you can use
the left/right arrow keys to center the frequency of
interest, and then use the up/down arrow keys to zoom
in or out in order to see more or less detail from the
scan.

With its constant, stable output, the AA-2000 ZOOM is
suitable for receiver sensitivity testing when used with a
good step attenuator, keeping in mind that the output
waveform is a square wave with multiple harmonics.
The AA-2000 ZOOM can zero-out a transmission line
for making accurate remote antenna feed point imped­ance measurements if open/source/load calibration
standards are available.

Table 2 displays the measured open-circuit impedance
of the AA-2000 ZOOM. This gives an indication of the
impedance magnitude you can accurately measure as
a function of frequency. I found these measurements
interesting, as all other antenna analyzers I’ve reviewed
measure a high open-circuit impedance (several thou­sand ohms) at low frequencies, but the measured
impedance drops off to low values (hundreds of ohms)
at the high end of the instrument’s range. The AA-2000
ZOOM measures virtually the same high open-circuit
impedance across its entire range.

Next I compared return loss (RL) measurements of
various loads using the AA-2000 ZOOM and my Array
Solutions VNAuhf vector network analyzer. I have found
the VNAuhf to be similar in accuracy to an HP/Agilent
8722D VNA over the frequency range covered by the
VNAuhf. However, I cannot measure frequencies above
1200 MHz with the VNAuhf.

For these measurements, I used return loss instead of
SWR because return loss is the preferred measure­ment method on the higher frequencies. You can easily
convert return loss to SWR using online calculators.

First I measured return loss using a precision 50 
load (see Table 3) and then I measured several open
and shorted microwave attenuators of 6 dB (12 dB
return loss) and 3 dB (6 dB return loss). Return loss
measurements were also made using a 2 dB attenu­ator (4 dB return loss), although the attenuator is only
specified to 500 MHz. These measurements are shown
in Table 4. As you can see in the tables, the measure­ment discrepancies between the AA-2000 ZOOM and

Other useful features available in the AA-2000 ZOOM
include the ability to measure cable length, cable loss,
velocity factor, and characteristic impedance. The TDR
function is useful for finding discontinuities in your
antenna system. One use for this is to determine the
physical length of coax to any of your antennas, just by
leaving the antenna end of the coaxial feed line discon­nected.

Using the AA-2000 ZOOM

I used the
some basic measurements. I first checked the 10 MHz
output frequency against the 10 MHz WWV signal, and
I could not discern any difference in frequency between
the two. Next, I checked the output level over the full
frequency range using my Mini-Circuits PWR-6GHS+
power sensor. It measured –9 dBm ±0.5 dB from 1.8
– 450 MHz, dropping to –11.1 dBm at 1 GHz and
–14.6 dBm at 2 GHz.

40 February 2022 QST www.arrl.org

ALL PARAMS

(All Parameters) mode for

Table 2
AA-2000 ZOOM Measured Open Circuit Impedance

Frequency Output (Z) Frequency Output (Z)
(MHz) () (MHz) ()

1.8 2,400 222 2,300
14 2,400 450 2,000
28 2,400 915 1,800
50 2,300 1,250 1,600
146 2,300 2,000 1,900

Table 3
Return Loss Measurements with

a Precision 50  Load

Measurements with the AA-2000 ZOOM compared to
Array Solutions VNAuhf

Freq. Return Loss (dB) Freq. Return Loss (dB)
(MHz) AA-2000 VNAuhf (MHz) AA-2000 VNAuhf

146 52 58 915 31 42
222 45 51 1,200 29 36
440 38 48 2,000 28 n/a

Reprinted with permission; copyright ARRL.