It makes a nice change to repair something like a childs’ toy. I know that if the repair works out, it’ll usually make someone very happy. However, having just said that, the repair I’m about to discuss, didn’t bring joy for all…
First off, I’ll get a moan out-of-the-way. Too many kids toys take too many batteries – it’s been like that since I was a kid. This does two things; makes the toy expensive to own and damaging for the environment when the batteries expire. Now, I know there are some very cool kids toys that rely on sophisticated electronics to make them work, but manufacturers: Please try to think harder about the toy’s overall impact on the environment and it’s in-life running costs.
OK, rant over.
On with the repair. This kids-chew-musical-keys is supposed to mimic an adults’ set of car keys. It doubles up as a teething chewy thing as well as an imitation car alarm blipper remote fob thing, that plays a tune. Delightful.
This set of keys had stopped playing a tune, when any button was pressed. To some, that might have been a good thing.
The battery compartment contained two LR44 coin batteries. These are found in many items and are readily available, if you know where to look, but are not commonly stocked in supermarkets, where I suspect most people buy batteries.
Taking the batteries out revealed some light corrosion on one cell, but no dramas. The other one was corrosion free. However, a quick test with the multimeter revealed that both batteries were kaput.
I usually keep a pack of LR44s (as one does) in case of toy key emergencies like this and luckily on this occasion, I had two shiny new ones to fit. But, upon installing them, replacing the cover and pressing one of the buttons for the first time there was still no sound. How odd. What I thought would be a quick battery change had escalated in to a full toolkit situation.
Whipping the back of the key fob apart revealed a simple integrated circuit with the battery terminals, all in good condition. The small piezo speaker was held behind the main circuit board and on closer inspection, I saw that one of the soldered connections had broken away from the speaker.
Solder repair jobs like this are difficult as excess heat can quickly transfer from the joint being operated on, to the whole component, causing damage if too much heat is conducted. I had to be careful.
After some careful soldering, the broken wire was reconnected, circuit board re-installed, casing screwed back together and batteries re-fitted. A quick tap of one of the buttons then revealed musical joy. After a couple of presses I then began to regret the repair…
Cost of replacement: Not sure, £5 ish? Cost of repair: A bit of soldering.