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Electronics => Repair => Topic started by: hpibmx on July 29, 2020, 02:53:43 pm

Title: Need help fixing my remote control
Post by: hpibmx on July 29, 2020, 02:53:43 pm
Hi,
I have this Logitech sound system in my house and recently 1 button which is lower volume stooped working.
I just tried to open it up and thought of cleaning the contact area but found out it’s button!
Any ideas how I can fix this?
Thank you for reading this.
Title: Re: Need help fixing my remote control
Post by: Renate on July 29, 2020, 07:09:49 pm
Is the mechanical snap action of the little metal cap snapping?
You might try to unsolder it and clean underneath with a cotton swab and a bit of alcohol.
To test the IR you can use a smart phone camera, the infrared will blast through.
Or, if you are careful not to short things, just connect a headphone across where the big LED is with alligator clips.
A click should sound like some crackling.
Title: Re: Need help fixing my remote control
Post by: Twoflower on July 29, 2020, 07:18:03 pm
Careful about the mobile cameras and IR. Some have very good IR filters build in. The main camera from my old Apple 4S for example is more or less completely IR-Blind (the secondary cam works). The same applies for the iPads. So you should try the cam first with a working IR remote to see if the cam is IR sensitive.
Title: Re: Need help fixing my remote control
Post by: magic on July 29, 2020, 08:26:05 pm
IR is certainly fine if other buttons work.

It's either the button or possibly corroded PCB trace. I would check the PCB first with a continuity tester and then worry about the button. Not sure what kind of thing it is and how to take it apart.
Title: Re: Need help fixing my remote control
Post by: tooki on July 29, 2020, 10:08:22 pm
Those are simple tactile snap domes under sticky tape. They’re not soldered. Just lift the tape to expose it. But before doing that, I’d test its continuity — the tape keeps contaminants out, so it’s unlikely gunk got in from outside.
Title: Re: Need help fixing my remote control
Post by: hpibmx on July 30, 2020, 12:52:00 am
Thank you all for your detailed reply I’ll test it with my iPhone 7 cam
And test for continuity
Then maybe lift up the sticky tape see if will do something 👍🏻
Title: Re: Need help fixing my remote control
Post by: CatalinaWOW on July 30, 2020, 01:41:26 am
The problem is most likely to be in the snap dome switch.  There are several possibilities.

1.  Your photo seems to show the dome shifted.  It is not placed over the pcb pads in the same way that the other domes are.  This has probably been this way since manufacture, and was marginally working - now has gone to marginally none working.  You may find that the dome gives continuity for some direction/placement of the pressure point.  Solution is to lift tape (lift as little as you can get away with) and move the dome.  While you are doing this clean the pad and bottom of the dome.

2.  The tape does work to seal out dirt, but it is not a gas tight seal and the adhesive itself can migrate causing problems.  Lifting the tape and cleaning can resolve problems in these switches.


3.  Silicon pad which is the actual button face you see on the controller may have a pedestal on the back designed to press on the dome.  This may have deformed/shifted due to the dome placement mentioned in 1.  The fix for 1 may also deal with this, or you might have to overcompensate, shifting the dome in the opposite direction to place it under the non deformed or shifted part of the pad.

4.  This is really unlikely but the dome itselve may have failed causing it to bend in ways that don't cause contact.  Replacement domes are available from many sources and some may be suitable replacements.  Or you can raid the local second hand store for remotes to cannibalize.
Title: Re: Need help fixing my remote control
Post by: hpibmx on July 30, 2020, 06:55:20 am
Thank you for briefing me step by step 🙏🏻