Restoring Remote Control

[johnb]

There are very helpful instructions in the wiki but I thought I would post a different method that I came across and which doesn't involve aluminium foil or conductive paint and which, so far (touching wood) seems to be very successful indeed on one of my remotes which got to the stage of being practically unusable.

(The method was suggested elsewhere.)

Needed:
isopropyl alcohol (Maplins stock it)
cotton buds
a pencil eraser (I used a plastic eraser, though the eraser at the end of a pencil was originally suggested)

- Open up the remote, as per the wiki.

- Gently swab the contact side of the PCB with cotton buds/isopropyl alcohol), a bit at a time, to clean the contacts - drying each section with a dry cotton bud and making sure that the cotton buds you are using are clean. (I suppose one should give the usual warning about static electricity affecting the components.)

- Take the rubber sheet (with push buttons and rubber contacts) and clean each individual contact with cotton buds/isopropyl alcohol, drying as you go and making sure you are using clean cotton buds (so that you aren't just moving the crud around).

- Use a pencil eraser (I used a plastic eraser which has a milder effect) to lightly abrade each of the contacts on the rubber sheet.

- Do another quick clean of the rubber contacts with cotton buds/isopropyl alcohol

- Allow time for any moisture to evaporate, then re-assemble

It completely restored an almost useless remote I had. That was a week ago, but I have no idea how effective the method is in the long term.

 

[Trev]

Is the 'rubber' itself conductive, or does it have a conductive coating. Seems like the latter, otherwise the eraser would just succeed in rubbing a coating completely off.

 

[Ezra Pound]

I suspect that you had success with this method because the rubber contacts were covered with something non conductive, this method won't work if the conductive rubber is no longer conductive, which tends to be the problem, cleaning which is essentially what you are doing won't help

 

[Trev]

That's why I asked if the whole rubber bit was conductive or just a coating on the pads.

 

[Ezra Pound]

That's why I asked if the whole rubber bit was conductive or just a coating on the pads.

As far as Humax remotes go I can't say as it would mean destroying the pads in order to determine this and I don't have a spare remote, however, I haven't yet found any remote pads with 'solid' conductive rubber, the ones I have examined have all been non-conductive rubber with a very thin conductive layer painted / sprayed on

 

[everthewatcher]

Is the 'rubber' itself conductive, or does it have a conductive coating. Seems like the latter, otherwise the eraser would just succeed in rubbing a coating completely off.

The black rubber pad is bulk conductive - I've not come across a keypad that doesn't use conductive rubber pads for some time although the quality can vary. You do see conductive ink used on cheap toys and the like, and I've seen foil used on single buttons.

A non-conductive layer can form on the most used keys which can easily be shifted by very light mechanical abrasion plus a wipe with isopropanol. The filthy remote that came with the broken PSU PCB HDR recently mentioned elsewhere had this on several buttons.

 

[everthewatcher]

My stock method is dismantle completely, put all parts including keypad but not PCB in water and give them as good a clean as needed with soap/detergent and a toothbrush. Carefully dry, using a non-linting cloth on the keypad.

Wipe the contact side of the PCB with plain water and/or isopropanol. You can sometimes find a clear syrupy deposit on the keypad and PCB. No idea what forms it but it's completely water soluble.

Check the conductive rubber pads for any showing a slight polish and abrade very, very slightly. I find scraping with a finger nail and a wipe with isopropanol is usually enough to ensure they work properly.

Check everything is fully dry and carefully reassemble back of case and PCB, making sure the battery contacts go into their slots correctly. Insert batteries, drop on the keypad but leave the top off. Check all keys work then fully reassemble.