EEVblog 1663 – BM786 Multimeter REPAIR + InEr Error Investigation

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/

Podcast: Download