Whether you're outfitting a new bench or upgrading an existing one, choosing an oscilloscope often comes down to a simple fork in the road: do you want a modern all-in-one digital tool, or a high-bandwidth classic with the connectors you've worked with for years? For buyers shopping for an oscilloscope with signal and spectrum analysis in mind, the FNIRSI DPOS350P and the Tektronix TDS 380 represent those two paths, with only a modest gap in price between them.
Quick verdict: If you want a modern multi-function digital scope, choose the FNIRSI DPOS350P. If you want a classic benchtop scope, choose the Tektronix TDS 380.
| Product | Price | Bandwidth | Sampling | Display/Extras |
|---|---|---|---|---|
| FNIRSI DPOS350P 4-in-1 | $225 | 350 MHz | 1 GSa/s | 7-inch 1024x600 LCD, signal generator, spectrum analyzer |
| Tektronix TDS 380 | $195 | 400 MHz | 2 GS/s | CRT display, RS-232, GPIB, video out, math functions |
Where the FNIRSI DPOS350P wins: The DPOS350P brings more than one measurement tool to the bench, so it can take on tasks beyond just waveform viewing. The high-resolution mode and fast waveform capture rate help with detailed analysis, and it's new open-box hardware, whereas the Tektronix is described as used.
Where the Tektronix TDS 380 wins: The Tektronix TDS 380 is built for work where signal fidelity matters, and it includes useful measurement conveniences like autoset and a hardcopy feature for documenting your captures. The built-in carrying handle doubles as a tilt stand, and if you're comfortable using used gear from the United States, this is a powerful classic.
4IN1 Digital Oscilloscope DPOS350P 350MHz 2CH Signal Generator Spectrum Analyzer
The FNIRSI DPOS350P is the modern choice, priced at $225. It combines a 350MHz oscilloscope with a signal generator and spectrum analyzer, so you can generate a test signal and analyze the response on the same screen. The 7-inch 1024x600 display makes waveform details easy to see, and the 1GSa/s sampling rate handles fast edges. The 8-bit to 16-bit high-resolution mode and 50,000 wfm/s capture rate are strong tools for troubleshooting. One limitation to understand is the adjustable hardware bandwidth limit of 150M/20M, which you may need to set depending on the signal you're measuring. Also, it's open-box, so it's not factory-sealed even though it's described as new. For a bench that needs multiple functions in a small footprint, this is a very compelling package.
Tektronix TDS 380 400MHz 2GS/s 2 Channel Digital Real-Time Oscilloscope Tested
The Tektronix TDS 380 brings a 400MHz bandwidth and 2GS/s real-time sampling rate to the table for $195. That's a higher bandwidth than the FNIRSI, and the 2GS/s rate gives you more samples for fast transients. The CRT display is a classic, but the real strengths are the measurement tools: autoset, measure menu, math functions, and hardcopy. If you need to talk to older equipment, the RS-232, GPIB, Centronics, and video output connections are invaluable. The included carrying handle and tilt stand make it easy to position on a crowded bench. What holds it back is the used condition, the fixed 8-bit resolution, and the fact that a CRT is not as easy to read as a modern LCD. But for a Tektronix with this level of performance and connectivity, it's a solid used purchase.
Final choice by use case: Choose the FNIRSI DPOS350P when you want one box that can adapt to many kinds of signal work. Pick the Tektronix TDS 380 when your priority is bandwidth, sampling speed, and a classic benchtop feel with the connections to match.
