teardown

Bootleg Battery Charger Teardown

| steelcityelectronics

Its amazing how cheap some stuff is on eBay these days.

For example, I picked up 3x lithium ion batteries and a charger to suit my Olympus TG-4 camera for $25 Aussie dollars, including free delivery.

I got this charger and 3x batteries (yes, I know, only 1 battery is shown) for about $25. This stuff is just too cheap and nasty.

I have an upcoming camping trip and I wanted to get some spare batteries for the camera.

I didn’t want to buy just 1 battery in case it was dead on arrival so I got 3. The battery charger was a bonus. Olympus don’t supply a proper battery charger when you buy a TG-4, you have to charge the battery in the camera with a USB charger and charge times are pretty slow. Olympus sells an AC powered charger but its about $70 and doesn’t include extra batteries. I was hoping that the new charger would be faster or reasonably good, but I didn’t have high hopes on the quality of the battery charger.

Two screws at the back of the charger were removed, but the plastic halves are ultrasonic welded together. Splitting the ultrasonic weld was very easy though. A bare minimum of plastic has been used and it isn’t very rugged.

It looks pretty crusty.

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4-20mA Panel Meter Teardown

| steelcityelectronics

I haven’t done a teardown in a while so I thought I’d share the insides of panel meter I recently found at a Sunday morning junk market for $5.

Below is a panel meter that has been used in some sort of industrial process. It was manufactured in 1980 by Kuwano. I’m not quite sure who the manufacturer was – the company’s logo is not easy to read but it might say, “Aumano”. What caught my attention with it was that it includes high and low needles as well as indicators and relay outputs for the high and low limits.

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Matrix MFG-8216A Function Generator Teardown and Repair

| steelcityelectronics

Hey folks, sorry for the long wait between drinks, a few things have been going on – holiday, work, demolishing a leaking bathroom.

Anyway, after years of telling myself to get a function generator and watching eBay for quite a few months, I finally took the plunge and bought one. A broken one. Yes, I bought a broken function generator from eBay.

faulty Matrix MFG-8216A function generator
The Matrix MFG-8216A function generator without sine wave output

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MJE3055 Power Transistor Teardown

| steelcityelectronics

Whats inside a power transistor? Well some semiconductor to be a transistor of course. How large would you expect the transistor’s die to be?

My guess is, that for a device that can conduct up to 10 A, the die would occupy the bulk of the transistor’s package. What’s your guess?

MJE3055 NPN transistor
An MJE3055 NPN transistor ready to be dismembered.

Lets find out with a teardown of sorts with the following MJE3055 NPN power transistor that comes in a TO-220 package.

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