The Tektronix TDS420A is a legacy 4-channel, 200 MHz digital storage oscilloscope designed to capture transient events with a maximum 100 MS/s sample rate and a 10 ns peak detect mode. It delivers high-precision signal analysis with ±1.5% DC gain accuracy, 25 built-in automatic measurements, and supports up to 120 K points of record length per channel (with Option XL). The instrument features dedicated video triggers, a roll mode for real-time waveform monitoring, and a built-in floppy disk drive for convenient data storage.
Specifications
General
| Parameter | Value |
|---|---|
| Interfaces | GPIB (IEEE 488.2) standard; RS-232 and Centronics (by option) |
| Display | 7-inch Monochrome CRT |
Physical
| Parameter | Value |
|---|---|
| Power Supply | 90 to 250 VAC, 45 to 440 Hz, 240 W maximum |
Vertical System
| Parameter | Value |
|---|---|
| Number of Channels | 4 |
| Analog Bandwidth | 200 MHz |
| Calculated Rise Time | 1.75 ns |
| Vertical Resolution | 8 bits (up to 12 bits in Hi-Res mode) |
| Input Coupling | AC, DC, GND |
| Input Impedance | 1 MΩ ±1% // 15 pF ±2 pF, or 50 Ω ±1% |
| Input Sensitivity Range | 1 mV/div to 10 V/div (1 MΩ); 1 mV/div to 1 V/div (50 Ω) |
| DC Gain Accuracy | ±1.5% |
| Maximum Input Voltage | 400 V (DC + peak AC) at 1 MΩ; 5 Vrms at 50 Ω |
| Offset Range | ±1 V (1 to 99.5 mV/div); ±10 V (100 to 995 mV/div); ±100 V (1 to 10 V/div) |
| Position Range | ±5 Divisions |
| Channel-to-Channel Isolation | >100:1 at 100 MHz |
Horizontal System
| Parameter | Value |
|---|---|
| Maximum Sample Rate | 100 MS/s |
| Maximum Record Length | 30,000 points/channel (120,000 points/channel with Option XL) |
| Timebase Range | 1 ns/div to 20 s/div |
Trigger System
| Parameter | Value |
|---|---|
| Trigger Modes | Auto, Normal, Single |
| Pre-Trigger Position Range | 0 to 100% of record length |
Acquisition System
| Parameter | Value |
|---|---|
| Peak Detect Minimum Width | 10 ns |
| Hardware Bandwidth Limits | 20 MHz, 100 MHz |
Measurements and Math
| Parameter | Value |
|---|---|
| Automatic Waveform Measurements | 25 built-in measurements |
| FFT | Supported (with Option XL) |
Interfaces and Connectivity
| Parameter | Value |
|---|---|
| Storage Media | 3.5-inch Floppy Disk |
| Probe Interface | TekProbe BNC |
Power
| Parameter | Value |
|---|---|
| Maximum Power Consumption | 240 W |
| Line Frequency Range | 45 Hz to 440 Hz |
| Line Voltage Range | 90 to 250 VAC RMS |
Display
| Parameter | Value |
|---|---|
| Display Type | 7-inch Monochrome CRT |
Environmental
| Parameter | Value |
|---|---|
| Operating Altitude | Up to 4,570 m (15,000 ft) |
| Non-Operating Altitude | Up to 15,240 m (50,000 ft) |
Triggering
| Parameter | Value |
|---|---|
| Trigger Coupling | DC, AC, HF Reject, LF Reject, Noise Reject |
Technology
Digital
Applications
Electronic testing, transient analysis, video signal monitoring, and general circuit debugging