Instrument authenticity guarantee
Every unit physically inspected. Real serial number in every listing. No remarked, cloned, or counterfeit instruments.
Why authenticity matters in used test equipment
The used test equipment market — particularly Keysight, Agilent, and Rohde & Schwarz instruments — has a documented counterfeit and remarking problem. Counterfeits are instruments that appear genuine but contain cloned or downgraded internals. Remarked instruments are genuine units with their model number altered to appear as a higher-specification variant — a 26.5 GHz spectrum analyzer relabeled as a 50 GHz model, or a basic signal generator remarked as an option-equipped version it never was.
The risk is real. A counterfeit signal generator used in calibration produces measurements that appear valid but are wrong. An OTDR with a falsified dynamic range specification mischaracterizes fiber span performance. The instrument looks right, the listing looks right, and the problem only becomes apparent when a measurement fails to reproduce or a calibration audit fails.
Every instrument listed on aumictechlabs.com has been through a physical authenticity inspection before it goes up. Here is exactly what that involves.
Our authenticity verification process
Serial number format verification
Every OEM uses a defined serial number format — length, prefix structure, character set. We verify the serial number on the physical instrument matches the OEM format for that model and date range. A Keysight E4438C has a known serial format; a number that does not conform to it flags the unit for additional inspection.
Physical label and chassis inspection
We inspect the instrument label under magnification for signs of remarking: mismatched fonts, adhesive residue from a removed label, paint overspray on or around the model designation, and inconsistent spacing or print quality relative to authentic examples. Chassis inspection checks for screw pattern changes, fill material in unused option holes, and mismatched serial plate finish.
Firmware and hardware revision cross-check
Each instrument model has a defined firmware version history and a hardware revision sequence. We verify that the firmware version present matches what the hardware revision should support, and that option flags enabled in firmware correspond to physical option boards installed in the instrument. An instrument claiming an option it does not physically contain fails this check.
Performance verification against rated specification
We run OEM self-tests and functional tests and verify the instrument performs within its rated specification. A counterfeit or downgraded instrument typically underperforms its labeled spec — a "50 GHz" analyzer that loses signal above 26.5 GHz, or a signal generator with phase noise 10 dB worse than specified. Performance testing is the final gate.
Real serial number in every listing
Every listing on aumictechlabs.com shows the actual serial number of the specific unit for sale. Photos show the physical serial number plate — not a stock image. If the serial number you see in the listing does not match the serial on the instrument you receive, contact us immediately. That is a listing error and is covered unconditionally.
What to look for when buying used test equipment anywhere
Whether you buy from us or anywhere else, these are the signs of a potentially remarked or counterfeit instrument:
- Listing uses a stock photo, not a photo of the actual unit
- Serial number is not visible or readable in any listing photo
- Price is dramatically below market for that model and condition
- Seller cannot answer questions about the instrument's source or history
- Firmware version reported in the listing does not match what that hardware revision should carry
- Model designation appears freshly painted or has a different finish than the surrounding chassis
- Self-test passes but measured performance does not match specification at key test points
If you bought an instrument elsewhere and suspect it may be remarked or counterfeit, we can perform an authenticity evaluation as part of our standard bench evaluation. Contact us with the make, model, and serial number.
Our guarantee
If any instrument purchased from Aumictech is found to be counterfeit, remarked, or materially misrepresented in its listing — wrong model, wrong serial, wrong specification — we cover return shipping and issue a full refund including original shipping cost. No time limit on authenticity claims. We keep bench records for every instrument we sell and can provide documentation of what was inspected and verified before sale.
Frequently asked questions
Are counterfeit test instruments a real problem in the used equipment market?
Yes — particularly for Keysight (formerly Agilent) and Rohde & Schwarz instruments. Counterfeits typically use legitimate-looking chassis and labels with clone or downgraded internal components. Common examples include cloned signal generators with inferior phase noise, downgraded spectrum analyzers with reduced frequency ranges, and instruments with falsified calibration certificates. Most counterfeits originate from gray-market channels in Asia.
How does Aumictech verify an instrument is genuine?
We verify serial number format against OEM serial number conventions, inspect for label overstamping or physical signs of remarking, confirm firmware version matches the hardware revision, run OEM self-tests and verify results match expected performance, and inspect internal components when accessible. We photograph the actual serial number plate in every listing — not a stock photo.
What is a remarked instrument and how do you detect it?
A remarked instrument is a genuine instrument with its model number or serial number altered — typically to represent a higher-specification variant. Remarking involves replacing or painting over the original label. Signs include mismatched label fonts, label adhesive residue, inconsistent serial number formatting, and firmware that does not match the labeled model. We check for all of these during physical inspection.
What if an instrument I receive from Aumictech turns out to be not as described?
Contact us immediately at sales@aumictech.com. We cover return shipping for any instrument that does not match its listing description, including any authenticity discrepancy. Full refund is issued upon return. We maintain bench records for every instrument we sell and can provide documentation of what was verified before sale.
Do you source instruments from verified sellers?
We source from production line decommissions, university lab sales, telecom operators, and known private party sellers. We do not buy from unknown international brokers or resellers who cannot identify the instrument's history. Every instrument is physically inspected before listing regardless of source — sourcing history reduces risk but does not replace the bench inspection.