Review: AEMC OX 7104-C handheld oscilloscope, part 2/3
Read Part 1 of this review or return to series introduction.
AEMC uses a touch screen with a stylus to enable or disable channels and navigate menus. Many functions have more than one way to activate: you can use the channel buttons or tap on the screen’s channel boxes. A single tap on a colored box turns the channel on or off. A double tap lets you change the channel’s V/div and coupling settings. I like dual access to settings.
The Vertical menu also lets you select the control box and trace color. If you use an AEMC probe, a menu letting you program the probe buttons will appear. When I used a direct BNC cable to the function generator, that area was grayed out. The menu (and channel buttons) provide access to channel math. You get basic math plus trigonometric and log functions on up to four math channels.It’s easy to set a simple display of channel 1*2 (double the amplitude). A channel can function as either a physical or virtual (math) channel. The math channels stay as math even when you connect a probe. They turn back to physical channels when you clear the math function. You can, though, recall saved math functions for easy setup.
You also get dual access to the Trigger menu from the screen or from a button. Select “Trigger Parameters” for main (edge), pulse, delay, count, or TV trigger setups through tabs. Here, you can select source and setups. Menu structure was easy to follow and intuitive. I tested the trigger setup with a digital signal. Using the stylus, I set the trigger by double-tapping in the trigger portion of the screen. I used cursors to find the width of an 8-µs pulse and used the Trigger menu to set the oscilloscope to trigger on a pulse that’s 6 µs wide or wider.
The Horizontal menu lets you select repetitive signal, min/max acquisition, averaging, or FFT. Under FFT, you can select rectangular, Hamming, Hanning, or Blackman window and log or linear scale. The Display menu lets you turn the grid on or off, select vector or envelop display, zoom, select full screen, and select oscilloscope-XY mode. You can also switch in and out of full screen by double-tapping the display area.
The Measure menu is essentially the same as pressing the “Auto Meas,” “Ref. Meas,” or “Curs ON/Off” buttons. It gives you access to all three functions. Automatic Measurements lets you select up to two measurements such as Vpp and Vrms for continuous display. The Memory menu lets you save traces in the oscilloscope’s memory that open with the oscilloscope’s software.
The Utility menu contains a file manager where you can open, export, or erase configuration, data, and math files. You can also setup communications (RS-232 or Ethernet) for connection to a PC. Read more about PC communications in Part 3.
I found saving a math function confusing. You get a sources list and a destination list; you must enter a file name in the source list, then tap an arrow to move the file to its destination. It took a few tires to figure out that I had to tap an arrow button to send the equation to its destination. You can erase math equations, but you have to do that through the Utility/File Manager menu.
Part 3 covers the DMM, logger, and PC software features.
Rick B commented:
