EEVblog

Repairing a customers Brymen BM786 multimeter, and investigating the cause of the InEr error message on the input jack alert feature.

Plus a giveaway to a local youngster.

00:00 – A returned BM786 Multimeter with InEr error message

03:23 – Split jacks and input alert circuit

05:19 – In-Circuit probing TIP and Low Ohms mode.

07:19 – A clue?

08:05 – A need a new desoldering gun. Removing the input jacks

10:30 – Bodge testing of the input detection threshold

12:38 – Not one but TWO failed Megger Insulation meters!

13:50 – Megger testing the connectors at 500V

15:19 – Testing a 2nd failed InEr error meter

17:00 – Cleaning the input jacks

19:11 – Heating up the input jacks

20:18 – Getting desperate, removing the input jacks

21:49 – Getting really desparate, removing the input resistors

22:38 – Reassembling the original repaired unit

24:26 – Repaired BM786 GIVEAWAY

Keysight OLED meter repair: https://www.youtube.com/watch?v=CKdeqqo2diI

Forum: https://www.eevblog.com/forum/blog/eevblog-1663-bm786-multimeter-repair-iner-error-investigation/