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Extech MS420 20MHz 2-Channel Digital Oscilloscope

Identify, analyze and calculate the frequency of waveforms quickly and easily using an Extech MS420 20Mhz 2 Channel Digital Oscilloscope.

Next Day Delivery (subject to availability)

£658.00 excluding VAT £789.60 including VAT @ 20% Regular Price: £954.59
  • Colour Oscilloscope
  • TRMS
  • Rechargeable Batteries
  • 2 channel, 20MHz
  • 6K points per channel
  • FreeDelivery
  • 30DayMoneyBack
  • Description
  • Features & Specification
  • Resources
  • Delivery

Extech MS420 20MHz 2-Channel Digital Oscilloscope

Extech's MS420 20 MHz 2-Channel Digital Oscilloscope offers a range of capabilities for effective troubleshooting of electronics and electronically controlled electrical systems. With 20 MHz bandwidth and conveniences like auto-set which optimizes the position, range, time base, and triggering to assure a stable display of virtually any waveform, the MS420 can be used in field repairs or bench duty.

To identify subtle problems, Peak Detect features a fast 50 ns glitch capture. Core functions like XY Mode, FFT function, Trigger Hold off, Waveform Math, Averaging Mode and Persistence Mode all ensure you can confidently troubleshoot problems using a variety of approaches. To start up recurring testing routines, you can store and recall up to 4 waveform screens and setups to save time from job to job. This CAT II-rated oscilloscope extends its functionality with complete DMM functions that are displayed on the large 3. 8" (97mm) color LCD display.

The Extech MS420 20MHz Oscilloscope can complete waveform math using addition, subtraction, multiplication and division and there is also an average mode which can be set for smoothing waveforms, as well as a persistence mode which enables users to observe dynamic signals.  True RMS multimeter functions are present in the Digital Oscilloscope and include AC/DC voltage and current, diode, continuity, capacitance and resistance.

The MS420 Comes Supplied With:

  • Extech MS420 20MHz 2 Channel Digital Oscilloscope
  • 2 x 1X/10X Oscilloscope Probes
  • Test Leads
  • USB Software and Cable
  • Capacitor Measuring Module
  • Adjustment Screwdriver
  • AC Adapter/Charger
  • Hard Carrying Case

The MS420 Comes Supplied With:

Key Features:

  • Auto-set function optimizes the position, range, timebase, and triggering to assure a stable display of waveforms
  • Peak Detect function for 50ns glitch capture
  • XY Mode and FFT function to view component frequencies
  • Twenty Automatic Measurements including Frequency, Cycle, Average, Peak to Peak, RMS and more
  • Waveform Math: Add, Subtract, Multiply, and Divide
  • Average Mode for smoothing waveforms
  • Persistence Mode for observing dynamic signals
  • Store and recall up to 4 waveform screens and setups
  • USB interface and software for transferring waveforms and data

ISSWWW and Extech

Since 1971, Extech Instruments has focused on Test and Measurement tools built for the professionals, tradesperson and DIY’ers. Our single source strategy has made us the brand to turn to when it comes to tools that help prevent, identify and troubleshoot problems in a plethora of applications; whether it’s electrical, mechanical, maintenance, safety or environmental applications, our products are trusted by the professionals and are put to the test every day.

Display Size 3.8" (96mm) color LCD; 320 x 240 pixels
Bandwidth 20MHz
Real time sample rate 100MS/s
Risetime 17.5ns
Channels 2
Record Length 6K points per channel
Glitch Capture 50ns
Vertical Sensitivity 5mV to 5V/div
Vertical Resolution 8 bits
Timebase Range 5ns to 5s/div
Sample Mode Sample, Average, Peak Detect
Trigger Modes Free Run, Single Shot, Edge, Video
Trigger Source CH1, CH2
Trigger Coupling AC, DC
Input impedance 1MΩ/20pF
Max Input Voltage 400V (peak)
Cursor Measurement Voltage and time
True RMS MultiMeter Functions
AC/DC Voltage 400mV, 4V, 40V, 400V
AC/DC Current 40mA, 300mA, 20A
Resistance 400Ω, 4kΩ, 40kΩ, 400kΩ, 40MΩ
Capacitance 51.2nF to 100µF
Diode and Continuity Yes
PC Interface USB cable
Power Supply 6 hours Li-ion rechargeable battery; AC Adaptor/charger
Dimensions/Weight 7x4.4x1.6" (180x113x40mm) / 24.3oz (690g)

Standard FREE 3-5 Day Courier Delivery – UK Mainland only - Zones A & B
Included in the price for all orders over £40.00 (exc vat). Sent using express courier, delivered within 3-5 working days from the date of your order, subject to availability.

Standard 1-2 Day Express Courier Delivery – UK Mainland only - Zones A & B
£4.50 for all all orders under £40.00 (exc vat). Sent by express courier, delivered within 1-2 working days from the date of your order, subject to availability.

Express Courier 1-2 Day Delivery – UK Mainland only - Zones A & B
£4.50 select at the checkout. Sent using express courier.

Next Day Delivery – UK Mainland only - Zones A & B
£8.00 select at the checkout. Sent using express courier, orders must be placed before 3pm for next day delivery, subject to availability.

Saturday Pre 12am - UK Mainland only - Zones A & B
£15.00 select at the checkout. Sent using express courier, orders must be placed before 3pm for Saturday delivery.

Orders must be placed before 3pm for next day delivery and a telephone number supplied, subject to availability.
Please note that predicted delivery times are based on regular trading days Monday to Friday. Public holidays, bank holidays and weekends are outside the usual scope of our dispatch and therefore may incure additional days lead time to your order.

Orders requiring calibration. Whilst we take the greatest care to get all orders dispatched and delivered to you in the stated time frame, orders received late afternoon and requiring calibration may on occasion miss dispatch that day, according to the complexity of the calibration. Be assured they will ship on the next dispatch, this in most cases should not add more than 24 hours to you delivery.

Delivery Surcharges
Because of the high cost of carriage we need to apply a surcharge on all deliveries made in the following regions bringing the carriage charges to:

  • Zones A & B  - Mainland delivery rates apply. 
  • Zone C - Scottish Highlands. 
  • Zone D - Outer Hebrides, Orkney Isles, Shetland Isles, Isle of Man, Scilly Isles, and Channel Islands.
  • Zone E - Northern Ireland
  • Zone F - Republic of Ireland

New Postage Map Sept 2018> 

International delivery

International delivery charges are automatically added to your order at the checkout; you can also use the guide below for a guide on prices. For any questions regarding international deliveries please contact us at

If no shipping option is available to your selected country please call us on +44 (0) 1603 406 148 to purchase your items.