Instructables
This is a four port USB 1.1 hub built on a tweety bird theme.
 
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Step 1: Getting the components together

First, the USB hub controller. Texas Instruments make, among others, one four port USB 1.1 hub in a 32 pin Quad package. They call it the TUSB2046. That is the black square at bottom right, in the picture.

It needs a regulated power supply of 3.3 volts, supplied by a three terminal low dropout regulator. Microchip make one, called the MCP1700T-3302E/TT though the actual chip is a tiny thing. Look carefully, you might just be able to identify it.

The other components were salvaged from various sources. The 6 MHz Crystal came from a Television set, where it was clocking the remote control microcontroller. The capacitors and resistors were unsoldered from various boards from junked equipment.

Step 2: The circuit board

The circuit board was partly etched, and the rest of the pattern hand carved using a hobby knife. No computer was used in any part of the production of the circuit board.

The only contact the circuit board had with any modern electronics was when it was photographed so that its picture could be displayed in this web site.

A piece of copper clad board was cleaned, and covered with etch resist ( I used a permanent marker pen ) and the integrated circuit clamped over it with alligator clips.

A needle was used to score fine lines where the copper was to be etched away, the ic removed, and the pattern finalised.

Then the board was made the anode in a tank filled with common salt solution with a straightened paper clip anode, and current passed till the pattern was completely etched.

This process, I feel, needs its own instructable and this I might do if wheedled / threatend / cajoled / asked / whatever works.
baubstae1 year ago
"The only contact the circuit board had with any modern electronics was when it was photographed"

This seems a bit silly given the complex IC about to be soldered to it. I don't see the point of this comment.
HomerS4 years ago
does there need to be a "system power on reset" ?? and what reset thing do i use. i found one that needs a sense thing using resistor, not sure what resistors to use.
rajendra1235 years ago
ok
chilll20095 years ago
Can you buy the stuff at radio shack???
9H1LO5 years ago
can we have a proper schematic for this? i will gladly make a proper pcb layout
neelandan (author)  9H1LO5 years ago
The schematic can be taken from the device data sheet available at TI web site. They recommend the use of more TI components in order to make it into a complete fully featured USB hub.
9H1LO neelandan5 years ago
there is lots of stuff on that datasheet i will try and remove what makes sense to me i already have the chip and i have MC33269DT33G as 3.3v regulator
emmotic6 years ago
I'm sorry im too stupid but, can you list the materials needed for this project? Thanks :)
Dael7 years ago
So I recently switched from my PC, which has sadly died, to my laptop, and I am finding myself short of USB ports. I was thinking, "Hmmm, I need a USB hub, and it would be awesome to build one". So I come across your Instructable and think, what luck! I was just wondering though, would you be able to post a schematic?
binnie Dael7 years ago
its cheaper to buy one than make. plus eaiser!
Dael Dael7 years ago
Nevermind, found one. =)

I was being lazy and completely forgot to check the data sheet app notes.

Anyway, great instructable!
mrmath7 years ago
You lost me. I couldn't follow it. Not because it wasn't a good instructable. I hae to say, I think it is a good one. It's because it had too many big words my little brain couldn't handle! I'm a wannabe. I wannabe able to do this kind of stuff.
binnie mrmath7 years ago
go back to geek school this is easy stuff the hardest bit about it is the smd
mrmath binnie7 years ago
There are many different types of geek. There's software geek. There's hardware geek. There's electronics geek. Science geek. Star Trek geek.... Just because I don't/can't follow what he's talking about with electronics doesn't make me less of a geek. It just means I took a different curriculum when I went to geek school.
binnie mrmath7 years ago
lol yea true true i fall under all those catagorys xcept the startrak one lol you sound a bit like my mum ( has a mental block on technology ) i havnt been to geek school yet, and im waiting till i leave school ( nother 4 years awww) But if your brain cant handle silly big words that make no sence to nobody why do you bother reading it. yes to learn good reason
neelandan (author)  mrmath7 years ago
There are more steps in between, because I popped the board onto my scanner every time my wife called me in for dinner, my daughter asked to sharpen my pencil, and the dog wanted to go out. When I am writing the text I shall take care to explain any large words. Wannabes can become tech experts if they want, and work, hard enough. Allow me to help.
Shriike7 years ago
How much does this project cost? I was looking for a usb hub and this looks like it might be fun
neelandan (author)  Shriike7 years ago
If you are looking for a USB hub - buy one. If, on the other hand, you wish to delve into the mysteries of self and bus powered hubs and what happens when a faulty device gets plugged into one and when your kid pushes a metal object into the USB receptacle - jump right in, and be prepared for a long journey before a completed hub gets engineered to your satisfaction.
cold_fusion7 years ago
Very nice, I have used FeCl before for etching but tend to use vero for projects because its nasty stuff. I would definitely like to see an instructable on your salt etching method. Keep up the nice project!
Does the etching process have advantages over the usual Feric Chloride method? If so I would be interested in seeing the instructable Pete
neelandan (author)  PeterTheUnGreat7 years ago
The salt doesn't etch until the current is switched on, while the FeCl is corrosive all by itself. For prototyping, where you can baby it along, I think the electro-etching process is better because of the less corrosive naure of the common salt. It is corrosive, however, and all traces must be removed from the finished board.
I messed around with this tonight, and all I got was rusty water! Does the copper board connect to positive (anode) or negative (cathode)? And do you think the salt concentration should matter much beyond conducting electricity? I'll play around some tomorrow, but I've got cooking to do too. -- Elliot.
neelandan (author)  The Real Elliot7 years ago
The PCB should be positive. If you got rusty water, then you made the iron +ve.
rotor neelandan7 years ago
I'd very much be interested in an instructable on this. I've stayed away from pcbs because I have a tiny house with a small child, and I'm not real keen on keeping strong acids anywhere the kid could get to it.
ajelliot7 years ago
Gotta know more about how you etched that board.
OK, I'll bite.

Table-salt-solution electro-unplating? That's freaking genius. How long does it take? Voltages? Etc?

I think you're right -- your method does need its own instructable. One reason I shy away from FeCl etching is the horrible chemicals, and what they do both to my sink and the environment at large. If you've got a better way, I'm dying to hear it.

Consider yourself cajoled.
neelandan (author)  The Real Elliot7 years ago
I use 12 volts from a 500 mA AC adapter (commonly called a wall wart). Only a small amount of copper needs to be etched away so the method is reasonably fast, around 5 - 10 minutes. I prefer using this because the salt solution, before and after the event, is only as corrosive as the original salt - ie, it is not a great thing to spill onto your table top or into your keyboard, but if you get it on your skin or clothes or the floor that's no great disaster. I've gotten rid of my store of FeCl and now get my PCB's done professionaly - those of my prototypes that work, and needs to be produced in 2 + quantity. I'm going to document it the next time I try another such board, but right now the tweety bird is taking up most of the little free time I get. Thanks for the encouragement.
Brilliant! Add me to the cajoling list too.
neelandan (author)  The Real Elliot7 years ago
I use 12 volts from a 500 mA AC adapter (commonly called a wall wart). Only a small amount of copper needs to be etched away so the method is reasonably fast, around 5 - 10 minutes. I prefer using this because the salt solution, before and after the event, is only as corrosive as the original salt - ie, it is not a great thing to spill onto your table top or into your keyboard, but if you get it on your skin or clothes or the floor that's no great disaster. I've gotten rid of my store of FeCl and now get my PCB's done professionaly - those of my prototypes that work, and needs to be produced in 2 + quantity. I'm going to document it the next time I try another such board, but right now the tweety bird is taking up most of the little free time I get. Thanks for the encouragement.
Vermin7 years ago
That's the funkiest prototyping method! I second The Real Elliot's request.
I too liked the 'knocked up in my shed' aesthetic of the project. Nice. Pete
ellinger7 years ago
Nice combination of old-tech and new-tech. Great re-use of parts. I fully expected to see a commercial hub disassembled and reassembled into the tweety bird. I am pleasantly suprised.