Out in Front

Color DSOs mimic analog-scope displays

LeCroy's 500-MHz-bandwidth LCS334 and 1-GHz-bandwidth LCS534 four-channel, color-display DSOs feature an "analog-persistence" mode that mimics analog-scope displays more faithfully than do other DSOs' displays. Most DSOs provide considerably less intensity information than do analog scopes, and, to compensate for this shortcoming, several color-display DSOs offer color grading. When you acquire multiple iterations of a waveform, the portions of the signal that occur in all or nearly all acquisitions appear in red; infrequent events appear in blue. The LCS334 and LCS534 provide not only color-graded displays, but also a wide Z-axis dynamic range, which enables the analog-persistence mode. In this mode, high-duty-cycle waveform elements appear with high intensity, whereas waveform elements that occur only sporadically show up faintly.

The scopes also feature acquisition memories as deep as 8M samples in single-channel mode, as much as 64 Mbytes of system RAM, and 1703125-mm displays. The CRT measures 10 in. diagonally, but only the central 9-in. area is visible. Of that, the display occupies only the central 8.3-in. region. These units also offer a mode in which the waveform display occupies the entire viewing area. When you shut off the menus, the waveform display enlarges, and, although you can still summon the menus, they float on top of part of the waveform.

The LCS334 and LCS534 use a 96-MHz PowerPC 603e mP, which performs waveform analysis and math without compromising control response. When the scopes are in single-channel mode, all waveform memory is available to the active channel. Similarly, the ADCs of unused channels can interleave with that of the active channel to achieve a maximum sampling rate of 2G samples/sec. Prices for a four-channel LCS334-series with waveform memory of 100k samples/channel and a real-time sampling rate of 500M samples/ sec/channel begin at $16,490. Prices for a similarly configured LCS534-series unit begin at $19,400.—by Dan Strassberg

LeCroy Corp, Chestnut Ridge, NY. (914) 578-6020, fax (914) 578-5985, http://www.lecroy.com.