Why Sampling Is the Only Realistic Way to Inspect
A line producing remote controls moves thousands of units a week. Checking every single one for every defect is not a quality system, it is a cost that eats the margin. So factories inspect by sampling, and the number that governs the whole thing is AQL — the Acceptable Quality Limit.
AQL 5% does not mean “5% of units may be defective and that is fine.” It means something far stricter: if the number of defects found in the sample does not exceed the acceptance number, the lot is accepted. In practice, for a two-sample plan at AQL 5% on a lot of 5,000 pieces, you pull 50 units and you are allowed zero critical defects.
The Three Defect Classes That Decide the Lot
| Class | Examples on a remote | Disposition |
|---|---|---|
| Critical | Non-functional on arrival: will not transmit, transmits the wrong code, button not detected, antenna disconnected | Reject the lot |
| Major | Functional but degraded: intermittent button, marginal range, visible housing defect, wrong label on a unit | Reject or rework |
| Minor | Cosmetic only: scratch, silkscreen misalignment, minor flash on an area not visible in the housing | Accept within AQL |
What a Critical Defect Means for a Remote
A critical defect on an RF remote is not a cosmetic scratch. It is a unit that transmits a code the receiver will never accept, a unit where the button reads as pressed when it is not, or a unit whose antenna is not connected. The customer experiences all three identically: the remote does not work, and they cannot tell whether it is the remote or the receiver.
That is why the critical class on a remote line is dominated by functional defects rather than appearance defects, and why the end-of-line functional test is the single most important station on the line.
The Station Sequence That Matters
- PCBA in-circuit test. Every board is tested against a golden sample in a fixture. This catches wrong components, cold solder joints and open circuits before they are ever potted.
- Button actuation check. Every dome switch is verified mechanically. A switch that reads intermittently is a field return that no amount of end-of-line testing will predict.
- RF functional test. The assembled unit is placed in a shielded box and the actual radiated signal is captured and compared against the code table for the specific market.
- Visual inspection. Housing flash, scratches, silkscreen alignment, battery door fit.
An inspection that only checks whether the unit powers on will pass every remote that transmits the wrong code — and that is the defect that reaches the customer.
How to Ask a Supplier for Evidence
- Ask for the AQL level, the lot size and the sample size in writing. A supplier who cannot state these is running visual inspection and calling it QC.
- Ask what the critical-defect definition is. If it only covers cosmetic defects, the functional test is not part of the inspection plan.
- Ask for a photo of the RF test box. If there is no shielded capture fixture, there is no signal verification.
- Ask how a failed lot is handled. Re-inspection, rework, or concession? The answer tells you whether their QC has teeth.
Request a Quotation — AQL Inspection
Send the model number, the band and the annual quantity. We reply with the exact part number, EXW price, MOQ and lead time. MOQ 100 pcs per SKU.
Send Inquiry on WhatsAppEmail: Joanna@rfmando.com · MOQ 100 pcs per SKU · 1 free sample per SKU ($30 DHL, buyer pays) · Lead time 7-15 days · T/T 30/70 · EXW Xiamen
Terms
MOQ 100 pcs per SKU. One free sample per SKU ($30 DHL, buyer pays). Lead time 7-15 days. Payment T/T 30/70. Prices EXW Xiamen. 100% functional test on every unit; a third-party QC report at AQL 5% is available on request. CE-RED, RoHS and FCC Part 15 documentation; RCM available.