Choosing a bench oscilloscope usually comes down to a trade-off: raw bandwidth or channel flexibility. These two real-time digital scopes sit on opposite sides of that choice. The Tektronix TDS 380 is a used high-bandwidth unit built around a CRT display, while the Siglent SDS804X HD is a new mixed-signal platform with an optional digital input path. Both have a place on the bench, but they are built for different kinds of work.
Quick verdict
If your signals fit a moderate bandwidth but you need more than one or two inputs, the Siglent SDS804X HD is the more complete package. If high-frequency work is your priority and a smaller input count is enough, the Tektronix TDS 380 gives you more bandwidth.
At a glance
| | Tektronix TDS 380 | Siglent SDS804X HD |
| Listed price | USD 195.00 | USD 461.00 |
| Price indicator | | |
| Condition | Used | New |
| Analog channels | 2 | 4 |
| Bandwidth | 400 MHz | 70 MHz |
Where each product wins
- Tektronix TDS 380: Wins on raw bandwidth and sampling speed. The front panel's Autoset, measure menu, hardcopy output, and math functions make everyday measurements simpler, while rear-panel RS-232, GPIB, Centronics parallel, and video output suit lab setups that need external logging or display. The carrying handle doubles as a tilt stand.
- Siglent SDS804X HD: Wins on input flexibility and modern measurement depth. Optional 16 digital channels turn the scope into a mixed-signal tool, and 50 Mpts memory plus 80,000 wfm/s waveform capture keep long acquisitions smooth. The HD front end is built around an excellent noise floor.
Product notes
Tektronix TDS 380
If high-frequency signals dominate your bench, the Tektronix TDS 380 brings 400 MHz bandwidth and 2 GS/s sampling to every measurement. That bandwidth is its strongest reason to choose it; two analog inputs handle many single- and dual-signal tasks, and the rear panel includes RS-232, GPIB, Centronics parallel, and video output for connecting to external gear. The integrated carrying handle that doubles as a tilt stand makes it easy to move between benches. The limitation is the input count: with only two channels, you cannot watch more than two related signals at once, and the 8-bit resolution is fixed. Since this unit is sold used, the condition of the specific instrument matters more than it would for a new scope. If your work fits a two-input workflow, this is a direct way to get high bandwidth.
Siglent SDS804X HD
The Siglent SDS804X HD earns its place when your measurements involve more than one or two points in a circuit. Its four analog channels let you watch several signals side by side, and the optional 16 digital inputs turn it into a mixed-signal scope for logic and analog work together. The 50 Mpts memory and 80,000 wfm/s waveform capture rate keep long acquisitions smooth, while the HD front end delivers an excellent noise floor. Watch the bandwidth before you buy: 70 MHz is not aimed at very fast edges or high-frequency harmonics. Also, the 16 digital channels require separate accessories sold apart from the scope. If your signals fit within its bandwidth and you value multiple input channels over raw bandwidth, this new instrument gives you a flexible platform that can grow as your measurements do.
Final choice by use case
Choose the Tektronix TDS 380 where maximum bandwidth matters most and the lower listed price fits your workflow. Choose the Siglent SDS804X HD for mixed analog and digital work within its bandwidth range, especially if you plan to add the optional logic probe later. In short, the Tektronix rewards a focus on signal speed; the Siglent rewards a focus on signal count and future capability.
