Button contacts dirty or ? - Page 1
Forum section: electronics / beginners

author: fixit7
author_rank: Regular Contributor
timestamp: July 04, 2019, 12:39:11 am
content: I am having to press down multiple times on some of the buttons to get that function to activate, especially the memory button.There is a thin film of plastic over those "silver things" that activate the various functions.Any ideas as to why it is happening?Thanks,AndyI am curious as to how the lcd display is used as there are no wires

author: ataradov
author_rank: Super Contributor
timestamp: July 04, 2019, 01:20:08 am
content: Sticky tape is just there to hold them for assembly. If you remove it, the silver dome will fall out and you will be able to clear the dust from underneath.LCD is connected using a zebra strip -https://en.wikipedia.org/wiki/Elastomeric_connector.

author: fixit7
author_rank: Regular Contributor
timestamp: July 04, 2019, 01:59:48 am
content: Quote from: ataradov on July 04, 2019, 01:20:08 amAs far as I can see, that plastic is needed to keep those contacts in position.I am reluctant to take it off for cleaning and then having a non-functional timer.

author: ataradov
author_rank: Super Contributor
timestamp: July 04, 2019, 02:02:15 am
content: There are multiple variants. some have alignment pins, others do not. If there are no holes in the PCB, then yes, yours do not.It is really not that scary and hard to disassemble. There is nothing precision about them.But if you do not want to clean them, then why post a question in a first place?

author: Gyro
author_rank: Super Contributor
timestamp: July 04, 2019, 09:11:50 am
content: I've had good success injecting contact cleaner into the contacts from the rear of the PCB. The problem tends to be contact oxidation, either the PCB centre contact or the stainless steel dome itself, probably both.The button centre contact always goes through a PCB via behind the centre of the dome, this is always an open (non-tented) via to allow air in and out as the dome is pressed. Just put a drop of your favourite contact cleaner/conditioner, Electrolube EML in my case, but probably Deoxit something in the US. Exercise the dome and you will see an air bubble appear when you press it and the cleaner drawn in when you release. Do this a couple of times and then wipe off any excess.I've done this on several dome contact remotes with long term success, in fact they tend to improve with time.

author: cvanc
author_rank: Frequent Contributor
timestamp: July 04, 2019, 12:07:48 pm
content: Remove the tape and the metal buttonsClean the PC board contact area under the buttonsClean the buttons (remove all old tape)Re-install the buttons using fresh tape (the tape is there just to hold the buttons in position)HTH.

author: fixit7
author_rank: Regular Contributor
timestamp: July 08, 2019, 03:31:41 am
content: Quote from: cvanc on July 04, 2019, 12:07:48 pmI did as you suggested.Formerly, the memory button needed to be pressed hard to work.Now, after using the contact cleaner, it no longer works.Working with those small metal buttons isnotnon-trivial.I had to use a very fine pointed tweezer to manipulate them and put them back into the correct positions as they used 3 sharp pointsto make contact with the board.I just cut the tape from around the memory button and used contact cleaner on it as that was the only troublesome button.I learned a lot.

author: ataradov
author_rank: Super Contributor
timestamp: July 08, 2019, 03:58:45 am
content: Well, obviously there are ways to screw up anything. But on a grand scheme of thing those buttons are not that hard to work with.Contact cleaner won't do much here. Just use regular alcohol on both the button and the PCB.Also there is a chance that the problem is not with the contacts, but wit some track on the board.

author: fixit7
author_rank: Regular Contributor
timestamp: July 08, 2019, 06:46:03 am
content: Quote from: ataradov on July 08, 2019, 03:58:45 amI believe you are living in la la land.With no evidence, you make statements that only criticize.

author: mikerj
author_rank: Super Contributor
timestamp: July 08, 2019, 09:05:33 am
content: Quote from: fixit7 on July 08, 2019, 06:46:03 amJudging someone's level of incompetence from their opening post is often difficult, cleaning this style of switch would be considered absolutely trivial by the vast majority of people on this forum, you don't even need to pick up a soldering iron. If you are having problems using sticky tape then perhaps electronics isn't for you?

author: fixit7
author_rank: Regular Contributor
timestamp: July 08, 2019, 11:19:04 am
content: Quote from: mikerj on July 08, 2019, 09:05:33 amI enjoy electronics and you will not dissuade me from continuing in my pursuit.:-)

author: fixit7
author_rank: Regular Contributor
timestamp: July 08, 2019, 01:14:13 pm
content: Quote from: mikerj on July 08, 2019, 09:05:33 ambraggart nounbrag·​gart | \ ˈbra-gərt\Definition of braggart: a loud arrogant boaster thinks he's a loudmouth braggart

author: tooki
author_rank: Super Contributor
timestamp: July 10, 2019, 11:25:02 pm
content: No, he’s not. Your posts consistently indicate that you are working on things well beyond your level of understanding. When we try to correct you, it’s not out of pride, but concern.