Review: AEMC OX 7104-C handheld oscilloscope, part 1/3

AEMC model OX 7104C, 100 MHz, price $5995.

(click here for the introduction to this series of reviews of four handheld oscilloscopes)

AEMC’s model OX7104-C Is the only four-channel handheld oscilloscope I tried and is the only one on the market. It’s 12-bit resolution and 100-MHz bandwidth put it high on the performance list. It’s also the only one with a touch screen interface and drop-down menus for setup and operation. These features come at a price: $5995. AEMC offers a two-channel model for $3995.

Although the instrument has menus, its designers put considerable thought into its buttons, which are nicely organized and color coded (see photo). Buttons are organized into vertical, horizontal, trigger, utility, measure, and function. Utility buttons are auto scale, hard copy, full screen mode, snapshot, screen contrast, and screen brightness. The vertical section has buttons to set the vertical and horizontal scales. I consider that an essential feature. The horizontal button section has a “Zoom” button. It lets you use the touch screen to select an area to zoom.

The oscilloscope’s touch screen is large and easy to see indoors. I tried it outside on a sunny day, too. The screen is visible outdoors if the screen isn’t in direct sunlight. The case has an adjustable hand strap on the left side.

AEMC uses a proprietary battery pack that resides under a cover that you can open with a coin. The AC adapter is large, but the power supply resides in the middle of the power cord. That’s good because the AC mains plug covers only one space on a power strip. The AC adapter uses a 4-position plug into the scope. You can only plug it in one way, but if you rotate plug plug, you might mistakenly try to force it into its socket.

A molded cover protects the AC adapter plug, RS-232/Ethernet connector, and calibration points. I found the cover difficult to place over the connectors. I also found that the cover frequently opens. (see photo).

The OX 7104-C uses a proprietary probe system. The probes connect to the top of the scope through attached adapters. Separate adapters provide direct connection to probes or BNC jacks for connecting cables. Another adapter provides banana jacks for DMM probes. You can mix and match channels among oscilloscope probes, DMM leads, or accessories such as current probes.

The probes come with a handy light that you turn on an off by pushing a button on the probe handle (see photo). Two other buttons are user programmable and provide you with any of the automatic measurements. When you connect a probe or adapter, the oscilloscope tells you which type of you’ve connected.

The probes come with a bag that includes several colored rings for identification. You can attach a colored ring to match the four channel colors (red, green, blue and magenta) on the oscilloscope’s screen. Or, you can change the colors of the four channel boxes on the screen. I found the red and green colors on the screen difficult to differentiate. If you have the same color blindness, try changing the colors so the red and green aren’t next to each other.

Continue to Part 2.