Remote whose buttons need to be held down

[haza]

I've got a remote controller which only works if you hold down the button for about 10 seconds. After the initial button works, subsequent buttons will work almost immediately if you use them straight away. But if you let the remote rest for a minute or so, you have to hold down a button again to make it "wake up".

I took it apart and had a look at the circuit which seems pretty simple. There is a single IC, a handle full of surface mounted resistors, and a single strange looking capacitor (it is yellow and perfectly rectangular, with the text "455 14" printed on it).

Anyone know what the problem might be? I've replaced the batteries for new ones which didn't change anything.

 

[davenn]

single strange looking capacitor (it is yellow and perfectly rectangular, with the text "455 14" printed on it).

Hi there
welcome to EP

that's a ceramic resonator 455 kHz, not a capacitor

using a cotton bud dipped in meths or isopropyl alcohol, clean both the pcb contacts where the buttons touch, as well as the black pads on the buttons
other than that, probably not too much else you can do
ohhh, there was one time when the resonator was damaged, after the remote had been dropped onto a hard wooden or concrete floor


Dave

 

[Kiwi]

Also use the cotton bud to clean the battery connections.
Check tension between the batteries and connectors.
Are you using 1.2v rechargeable batteries instead of 1.5v dry cells?
Are you using good quality batteries?
I assume you have tried new batteries.
Try gently pressing components on the circuit board at the same time as operating a button.

 

[mr fixit]

Also use the cotton bud to clean the battery connections.
Check tension between the batteries and connectors.
Are you using 1.2v rechargeable batteries instead of 1.5v dry cells?
Are you using good quality batteries?
I assume you have tried new batteries.
Try gently pressing components on the circuit board at the same time as operating a button.

I've got a remote controller which only works if you hold down the button for about 10 seconds. After the initial button works, subsequent buttons will work almost immediately if you use them straight away. But if you let the remote rest for a minute or so, you have to hold down a button again to make it "wake up".

I took it apart and had a look at the circuit which seems pretty simple. There is a single IC, a handle full of surface mounted resistors, and a single strange looking capacitor (it is yellow and perfectly rectangular, with the text "455 14" printed on it).

Anyone know what the problem might be? I've replaced the batteries for new ones which didn't change anything.

Like has been said, clean the buttons and contacts, but be aware, the stuff they make the button contacts out of, isn't very resilient. You will probably clean it all off.
Now, testing - very easy if you have a digital camera or mobile phone with a camera.

Simply point the remote at the camera and press a button. Looking at the camera view finder you will see the infra-red led glow if it is working.
This will give you an idea if the remote wakes up straight away or sleeps for a while.

 

[haza]

I've cleaned the circuit board with alcohol but not the rubber contacts, I'll try that but I'm not too hopeful.
The batteries are normal 1.5V ones, brand new, and they power other devices just fine.

Is it worth replacing the ceramic resonator? It's the only component that looks like it can be replaced easily, apart from the infrared LED (could that be the problem?). It also has another red LED that tells you if it is working or not.

 

[haza]

New discovery! Once the remote is warmed up and working, there is a LED that blinks rapidly while the button is held down (this is how I know it is working). If i push down on the resonator, the LED blinks much slower. Sign of a bad a resonator?

 

[davenn]

possibly or a dry solder joint

 

[haza]

I've order some new resonators from ebay. Local store didn't have any. They were dead cheap so not much to lose. We'll see how I go.

 

[haza]

I apologize for reviving a dead a thread, but I thought I'd post an update for anyone who comes searching for answer.

I replaced the resonator on the remote which completely fixed the problem. It was a cheap and easy fix.

 

[davenn]

I replaced the resonator on the remote which completely fixed the problem. It was a cheap and easy fix.

have seen that one on occasions ... mainly if the remote has suffered a few drops onto a hard floor ( no carpet)

well done
thanks for reporting back