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Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →The Iso-Tech 622 is the Iso-Tech ISR 622, a two-channel, 20 MHz analog oscilloscope with a monochrome CRT display. It is a legacy bench instrument for viewing repetitive waveforms—not a digital storage oscilloscope with sampling memory, USB capture or protocol decoding.
Most units now appear through used, surplus, repair or refurbishment channels. Buy one for analog learning, basic troubleshooting or restoration only when the display and major functions have been demonstrated; an untested “for parts” unit should be priced as a repair project, not as a working oscilloscope.
Quick verdict
- Best for: electronics education, audio and analog circuits, power-supply ripple, oscillator checks, repetitive low-speed logic and vintage test-equipment restoration.
- Not suited to: single-shot events, waveform logging, USB screenshots, automated measurements, serial-bus decoding, fast microcontroller work or high-speed switching analysis.
- Buying reality: condition, calibration, probes and safe shipping matter more than the model number. No current first-party product page or active manufacturer sales channel was identified.
What exactly is the Iso-Tech 622?
The full designation is Iso-Tech ISR 622, part of the ISR 6xx family. Search listings may use “Iso-Tech 622”, “ISR622” or “Iso-Tech oscilloscope 622”; use the complete ISR 622 marking when matching manuals or parts. The number “622” by itself is ambiguous on the wider web.
This is a conventional analog oscilloscope. A CRT draws the live trace, and front-panel controls set vertical gain, sweep and triggering. Catalog databases sometimes show fields such as “embedded operating system” or “0 digital channels”; those are generic metadata and do not indicate a digital storage architecture. The product overview identifies the instrument as a two-channel analog scope: All About Circuits ISR 622 overview.
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#1 Best Overall
- Quickly & efficiently determine the integrity of cables, windings on motors & transformers, and numerous electrical equipment & installations
- Automatic calculation of polarization index (PI) and dielectric absorption ratio (DAR)
- Fast-measurement design, faster & stable resistance reading, higher efficiency
- Voltage alarm function and complies with CAT IV 600V standard
Iso-Tech ISR 622 specifications
The table separates historical catalog data from figures reported by a reseller. Treat the original manual and markings on your particular unit as authoritative, especially for safety and input limits.
| Specification | Reported value | Qualification |
|---|---|---|
| Instrument type | Analog benchtop oscilloscope | CRT-based |
| Bandwidth | 20 MHz | Consistent across listings |
| Channels | 2 analog | No digital channels |
| Display | Monochrome CRT | Historical distributor description |
| Graticule | 8 × 10 divisions | Historical distributor description |
| Rise time | 17.5 ns | Historical distributor catalog |
| Vertical sensitivity | 1 mV/div to 5 V/div | Historical distributor catalog |
| Timebase | 0.1 µs/div to 0.5 s/div | Historical distributor catalog |
| Sweep magnification | ×10 | Historical distributor catalog |
| Triggering | TV-H and TV-V synchronization; trigger-level lock | Historical distributor catalog |
| Hold-off | Variable | Historical distributor catalog |
| Calibration output | Probe-calibration output | Historical distributor catalog |
| Maximum input | 400 V AC + DC peak | Historical figure; not a universal probe, CAT or mains-work recommendation |
| Approximate dimensions | 455 × 150 × 310 mm | Reseller-reported; verify against the manual |
| Approximate weight | 8.3 kg | Reseller-reported; verify before shipping |
| Input impedance/capacitance | 5 kΩ and 25 pF | Reseller-reported, not confirmed by an accessible factory datasheet |
| Operating temperature | 0–40 °C | Reseller-reported |
| Safety category | CAT II 300 V | Reported by reseller; do not equate it with the 400 V AC + DC peak figure |
The historical specifications come from the RS catalog PDF: RS historical catalog. Reseller-only physical and input details are listed by Rohm Chip.
What those features mean in practice
20 MHz bandwidth and 17.5 ns rise time
Bandwidth is the frequency at which the vertical response has fallen by the specified amount; it is not a promise that every 20 MHz waveform will be measured accurately. For amplitude and edge-shape work, choose signals substantially below the limit. The 17.5 ns rise-time figure is consistent with this bandwidth class, but it does not make the ISR 622 a modern digital-analysis instrument.
Rank #2
- Insulation Tester Type:Multifunction; Insulation Testing Voltage:50V, 100V, 250V, 500V, 1kV, 2
- 5kV; Insulation Testing Resistance:10Gohm to 200Gohm; Operating Temperature Min:-10°CThis listing is for Each
Two analog channels
CH1 and CH2 let you compare two live signals—for example, an input and output, clock and data, or ripple and load response. There is no waveform memory, sampled record or digital math engine.
CRT display and 8 × 10 graticule
The rectangular monochrome CRT and internal 8 × 10 graticule support direct voltage and time estimates. A healthy tube should produce a bright, focusable, centered trace without severe burn-in.
Trigger, hold-off and TV synchronization
Trigger-level lock and variable hold-off help stabilize repetitive waveforms, while TV-H and TV-V synchronization target older video timing. These controls are useful for learning analog triggering, but they do not provide protocol decoding or automated event capture.
Rank #3
- 【500V Insulation Testing Accuracy】Perfectly compatible with the Supco M500 electronic megohmmeter, this premium insulation tester offers a max 1000 megohms testing range at 500V AC. It accurately detects hidden insulation faults and aging issues on HVAC systems, motors, transformers and electrical panels, preventing electric leakage and short circuit risks.Please note test readings are for reference only and do not provide full compressor diagnostic data.
- 【Effortless Operation】Designed with a user-friendly resistance scale, this HVAC megohmmeter clearly displays insulation conditions in three intuitive grades: Good, Normal and Risk. No complicated data calculation or professional skills required.
- 【Ultra-Portable】Equipped with a premium soft carrying case, it effectively protects the device and accessories from dust, scratches and damage. The lightweight and compact design fits all standard HVAC service tool kits, enabling convenient portable testing for outdoor and on-site jobs.Package includes megohmmeter and soft carrying case only. C-size batteries and test leads are not included and sold separately.
- 【Durable material】Featured with heavy-duty double-sided ABS housing, this electronic megohmmeter boasts excellent impact, wear and friction resistance. It can withstand frequent collisions, drops and harsh working environments in industrial maintenance and HVAC engineering work. The sturdy build ensures long-term stable performance, effectively reducing equipment maintenance and replacement costs.
- 【Warm Tips】We provide a 2-year warranty for this product.
×10 sweep magnification and calibration output
×10 magnification expands part of a sweep for closer timing inspection. The probe-calibration output provides a known repetitive signal for checking probe compensation and basic channel response; it is not evidence that the entire oscilloscope is currently calibrated.
What can it measure realistically?
- Audio-frequency signals and analog amplifier stages
- Function-generator sine and square waves
- RC and RL transient demonstrations
- Power-supply ripple and regulator behavior
- Relay, motor-control and other low-speed switching waveforms
- Basic frequency, phase, duty-cycle and signal-presence checks
- Educational laboratory exercises involving repetitive signals
As frequency, edge speed or required accuracy approaches the 20 MHz limit, displayed amplitude and timing become less trustworthy. Use a suitable attenuating probe and verify compensation before making measurements.
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Manual and documentation
The documented manual is a combined instruction manual for Models 635, 622 and 658, rather than a booklet dedicated only to the ISR 622. All About Circuits lists a manual page at Iso-Tech ISR 622 manual, but that page includes a report that the download was not loading. A link therefore confirms that a manual is referenced—not that a readable PDF is currently accessible.
Rank #4
- Professional Resistance Tester: The insulation resistance tester Accepts all standard banana plug type connection test leads so you can use your existing meter leads with gator clips etc or use the included test leads which work find also great little meggerohmeter with up to 1000V testing and reads up to 5GOHMS of resistance, Has a 750AC volts setting so you can check to ensure your cables/equipment are de energized for insulation testing safely
- Easy Operation: The electrical tester has a high-definition LED large-screen display, the maximum display is 9999, automatic backlight, the backlight automatically turns on when measuring, and turns off when it stops, the megaohm meter reading can be clear even in dark environments
- Energy Saving And Power Saving: Megohmmeter tester Low battery warning display, the instrument will automatically shut down after 10 minutes without operation, long battery life, and there will be a red warning light when high-voltage output to ensure safety and efficiency
- Wide Use: The insulation tester is suitable for measuring the insulation resistance of electrical equipment and insulating materials such as transformers, motors, cables, switches, electrical appliances, and maintenance, testing and verification of various electrical equipment
- Quality tool for testing and inspecting electrical equipment: insulation tester 1000v It is a quality tool for maintaining, testing and inspecting electrical equipment
When evaluating a scan, check that it names ISR 622, matches your front-panel controls and covers the correct mains-voltage version. Archive copies and distributor databases may differ in scan quality or completeness.
How to test a used ISR 622 before paying
1. Inspect the CRT and case
- Power it on and confirm a visible trace appears without prolonged flicker or intermittent loss.
- Test intensity, focus, astigmatism (if fitted), horizontal/vertical position and beam centering.
- Look for severe burn-in, dim emission, uneven brightness or a trace that cannot be focused.
- Check knobs, switches, feet, handles, vents, screws and the mains lead for damage.
2. Exercise both vertical channels
- Test CH1 and CH2 separately with the same known signal.
- Change coupling, volts/division, position and variable controls; each should respond smoothly.
- Compare displayed amplitude between channels and watch for noise, distortion or intermittent operation.
3. Check sweep and triggering
- Run the timebase through its range and verify that the trace remains usable.
- Engage ×10 sweep magnification and confirm the expected expansion.
- Apply repetitive sine and square waves, then adjust trigger level and source.
- Change frequency and amplitude to ensure the trace locks rather than free-runs or drops out.
4. Verify calibration output and accessories
- Check that the probe-calibration terminal produces a signal.
- Ask exactly which probes are included; one reseller listing indicates that probes may be absent even when a power cord and instructions are supplied.
- Confirm probe attenuation, compensation, voltage and CAT ratings separately. Never infer probe safety from the oscilloscope’s input specification.
5. Treat safety and shipping as part of the test
Inspect the plug, fuse arrangement, case and exposed connectors. Have an electrically competent technician inspect older equipment before opening or servicing it. The historical 400 V AC + DC peak figure is not permission to probe mains or high-energy circuits. At about 8.3 kg, the scope is vulnerable to shipping shock; local pickup or professional packaging reduces risk.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.“Tested,” “untested” and “for parts” are not equivalent
| Seller wording | What it establishes | What to request |
|---|---|---|
| Tested | Some functions were checked, but scope and depth vary | Which channels, sweep, trigger, CRT and calibration output were demonstrated? |
| Untested | No working condition has been established | Assume faults until you can inspect and power-test it |
| For parts or not working | Repair, missing accessories or hidden faults are likely | Buy only as a repair, parts or restoration project |
| Unable to fully test | Critical functions such as display, gain, sweep or trigger remain unknown | Require a return option or price it below a known working unit |
An observed eBay listing asked US $300 while describing the ISR 622 as “for parts or not working,” unable to be fully tested and sold without returns: example listing. That single asking price is not a working-market valuation.
Best Value
- Wide Testing Range for Any Job - Handle insulation resistance tests up to 2000MΩ with selectable voltages of 250V, 500V, or 1000V. Perfect for troubleshooting motors, transformers, and industrial wiring systems.
- Clear & Easy-to-Read Display - Large LCD screen with dual readout makes it simple to monitor insulation resistance and test voltages, even in dimly lit or busy environments.
- Hands-Free Operation When You Need It - Convenient lock power-on function allows continuous testing without holding the button, making repetitive insulation checks safer and less fatiguing.
- Built Tough for Professionals - Rugged design ensures durability for field technicians and maintenance crews, with reliability you can count on in demanding electrical and industrial applications.
- Complete Kit Ready to Work - Includes test leads, batteries, and carrying case, so you can get started immediately. Ideal for electricians, HVAC techs, and plant engineers who need accurate results fast.
Who should buy one?
Good fit
- Students learning volts/division, timebase and analog triggering
- Hobbyists working on audio, analog and low-speed circuits
- Collectors and restorers who enjoy CRT instruments
- Owners who can service or calibrate vintage test equipment
Poor fit
- Engineers needing screenshots, waveform files, automated measurements or USB/LAN control
- Debugging serial buses or fast microcontrollers
- Single-shot transient capture and long event recording
- Safety-critical or production measurements requiring current calibration certificates
Repair, refurbishment and alternatives
If you already own an ISR 622, a specialist quotation may be preferable to guessing at a marketplace purchase. Lektronix lists repair, refurbished replacement and service-exchange options, subject to availability and quotation; its page states that repair and refurbished options carry a 12-month whole-of-unit warranty for applicable services: Lektronix ISR 622 service page. Compare shipping and repair costs with a working modern scope before authorizing work.
Choose a modern entry-level digital oscilloscope when you need storage, screenshots, automatic measurements, connectivity or protocol tools. A newer used digital scope from a major test-equipment maker may offer better documentation and service support. If CRT operation is the goal, a better-documented used analog model can reduce the effort of finding manuals and parts. Specific replacement models and prices require a current market comparison.
Bottom line
The Iso-Tech ISR 622 remains a capable basic analog bench scope when its CRT, two channels, trigger system and sweep are healthy. Its 20 MHz bandwidth suits repetitive audio, analog, power and low-speed logic work, but it cannot replace a digital storage scope for capture, decoding or computer-assisted analysis. Buy only with clear functional evidence, appropriate probes, safe packaging and a price that reflects calibration risk; treat an untested, no-return unit as a restoration project.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
