anyone else interested in (simple) electronics? By Deleted (Read 1,686 times)

[Deleted]

besides lanterns and engines i'm also interested in simple electronic circuits. I picked up this charger from dollar tree the other day and was curious to see the layout inside such a small unit.

heres the name plate. I really don't think this is capable of outputting an amp as it says. youll see why in a moment.

here it is pulled apart. you can see how small the DC/DC converter chip is. I don't think it would be able to put out an amp while reducing the voltage from 12 to 5 for USB without burning up from dissipating the excess voltage as heat. this is about the most basic DC/DC converter ive seen. just a few filtering caps, a diode and an inductor. the numbers on the IC were too small to read. at least they bothered to put a fuse in line. 1.5 amps

I threw it back together and hooked my phone to it. it charged, but very slowly and the unit itself got quite hot. not expecting it to last long.

does anybody else like taking things apart to see how they work? ive always done this. just curious I guess.

[t84a]

Too cool. Amazing that people will plug a $700 iPhone into that piece of crap. Thanks for posting. Very neat.

[cyborg]

Electrons and I don't get along very well,,,

[t84a]

My current project is trying to make my own remote gauge for my underground propane tank. I figured out exactly what I need to do but now need to figure out how to do it.

[jct842]

Some how spec's can be fudged and no one cares. Now try that with food or drug ingrediants and feds step in.

I completed a 1440 hour electronics course in 64. Was taught volts times amps equals watts. Fast forward a few years with solid state audio. Right on the bottom or back tag of an amp said total power is 90 watts...front of amp says 100 watts each channel. Must be a watt amplifier! In later years they say peak power. You still can not get more out of a device than you put into it.

Your device for charging must be rated in "peak power"!!!

We computed the voltage across an 8 ohm speaker at its rated wattage and it came out well over 220 volts....so....we hooked it up to an electrical outlet at 110 volts ac and of course it instantly smoked. Turns out speaker wasn't what they claimed it was. This was before the manufacturers inserted the "peak power" into their claims.

[Deleted]

yeah. I have no way of testing it easily. I could take apart a USB cord and load it down to 1 amp and check the voltage and see. I don't think we really need to though seeing how small that IC is.

[jct842]

It is really not got that much going thru it. 1 amp times 5 volts is only 5 watts. If it is slow charging, the 5 volts may not be 5 volts but some what lower.

[Deleted]

Jan 19, 2015 20:17:01 GMT -6 jct842 said:

It is really not got that much going thru it. 1 amp times 5 volts is only 5 watts. If it is slow charging, the 5 volts may not be 5 volts but some what lower.

I've seen actual specs for chargers like this that will only be outputting 3.5v when at their rated load (1a). Pretty poor, i think.

If they're a cheap charger meant for 110v mains power sometimes at high loads they put out very dirty power. Some things just won't work with them because of the interference.

[richardv]

I've always wondered about those little thingies. My adapter for my phone, laptop and gps is at least 5 times that size and it gets warm. I've dismantle many things and then decided to take a home course in electronics with lab followed by computer repair in the '90s. NRI I think. And read a lot of magazines where you could buy kits that you assemble. I never got as far as etching my own pc boards. Then in '03 I had a break-in and they took all my equipment and I never got back to it.

[Bashan]

Yeah, I dismantle everything. I've learned a lot about electronics talking with Jack but I'm still no electrician. The last few scooters I bought the wife made me promise to not take them apart. Well I didn't, for a while, I didn't say how long I'd wait. I rewired my wife's Puma with some help and parts from TVnACman John. Now I'm repairing computers and the business is starting to take off. I like taking them apart and see what's in them but you just have to accept what they do and not try to figure out all the switching capabilities of the capacitors. I know Gman says he understands all the switching on a PCB but I don't, I just let the mobo do it's work and try to understand what can hook to that board and what can't. They are making computers now that have NO MOVING PARTS! How does a machine do billions of switching operations and have NO MOVING PARTS. Hell, even Robbie the robot on Forbidden Planet had mechanical switches! Oh, even the fans have no moving parts, imagine that.

[royldoc]

I love electronic devices. I am curious as to how they are designed and built. I and am constantly fulfilling that curiosity by taking things apart and trying to repair or salvage them for components. I was schooled in electronics back when you could actually see the components. They were mostly vacuum tubes, resisters,capacitors,ect. and you could tell what they were without the use of a powerful magnifying glass or microscope.

Roy

[Guitarman]

I learned electronics starting when I was around 7. By the time I was 8 I could repair a data bus by re-soldering the connections. My Dad was General Manager CI-MEG Division of NCR. When I got out of school I'd hang out in the lab at his office while waiting to go home with him when he got off work.
The Engineers would make me learn all kinds of stuff. They'd tell me rather than running around getting in trouble I was going to learn something.

The Army put me thru school for it also.

Had a computer business for 24 years and EVERYTHING changed. All the basics are still there, I over E times R and all that. LOL But motherboard design has bypassed what I'm familiar with. I suppose if I really had to... But why? It's become cheaper to replace than repair.

I love taking things apart and finding ways to improve on them but I just don't have the room anymore. It takes a workbench at the very least.

I've a project I'm working on right now because it's really small. So far anyway. LOL

[jct842]

The electronics seems to be changing so fast they may run out of places to go with it. Believe it or not I worked for a couple years in the engineering dept at oak manufacturing co. building tv tuners from scratch for engineering samples. The old clunky switch type tuners with tubes in them! 12 position gang switchs! UHF was a separate tuner.

[Guitarman]

I love those old tuners. If you had the right kind of steel, you could actually change channels by rattling a chain instead of using the remote. LOL

[jct842]

When you talk remote on those old black and white tv's you were talking rube goldberg. Zenith was the first, they used a mechanical transmitter, a chime affair with 4 rods slightly different, about 1/4" in dia and maybe 3 1/2" long that were struck with a clicker affair. Magnavox used 4 ultrasonic whistles activated by a bellows. It was the start of fat america!