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1 printed with a similar-looking code.

Nothing is printed exactly B2

This part is printed with a character that is easy to misread as what you typed. The odd one out is marked on each.

  • EIA-96:82printed 820603Precision resistor (EIA-96 code), 2 pins

    Printed 82 on the part. Easy to misread as B2. Check that character with a loupe before you order anything.

    What it is
    Precision resistor (EIA-96 code)
    Maker
    Not recorded
    Package
    0603
    Pins
    2
    Details
    EIA-96 precision chip resistor, significand 69.8; the printed mark adds a multiplier letter (82A = 698 Ohm, 82B = 6.98 kOhm)
    Source
    Added by hand from a published table

    Is it dead?

    Ohms range, across it, power off.

    Working, it reads

    Its marked value, within tolerance. On the board it reads the same or lower, because everything around it sits in parallel.

    Dead, it reads

    • Open: burnt, cracked, or eaten through by sulphur. The commonest failure.
    • Well above its marked value: drifted high.
    • On the board, clearly higher than its marked value: it has failed, since the board can only pull a reading down.
    On the board:
    A reading lower than marked on the board proves nothing; lift one end. A reading higher than marked is a fault even on the board.
    Compare:
    The same position on another channel usually carries the same value, and so does the matching part on another board.
    Watch for:
    A burnt resistor usually means the part it feeds pulled too much. Find that before fitting a new one, or it burns too. The marking, not the reading, says what to fit.

    A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.

    Datasheetfor EIA-96:82, opens in a new tab

One code, several parts

Marking codes are not unique. In the standard code book, 6H on a SOT-23 is an NPN transistor, a varicap, an N-channel JFET, two digital transistors, a 3.6 V voltage detector: six parts from five makers. So a search shows the parts we hold under that code and under codes easily misread as it, with only the columns that tell them apart.

6Hon a SOT-23, in the code book
  • NPN transistor
  • Varicap
  • N-channel JFET
  • Digital transistor ×2
  • 3.6 V voltage detector

When more than one is left

Tap Help me choose. Up to 4 quick answers: whether the part has failed, then what separates the parts left. Those get ranked with the reasoning and a test that settles it. That uses one identification; 3 a month are free.

When you cannot read it

Tap the camera in the field. We read the characters, keep the ones we are unsure of, and search every reading. A photo too soft to read is turned back on your phone first; if it is the only one you can get, you can still send it.