Homemade Usb Passthrough

[Firdaddy]

if you have a EPO or eletronics supply store local go ask them, they're normally VERY helpful.. i cant think off hand what resistor to use.. if you had 12v i could help you, thats what i'm use toFrown

[Royal]

I would probably guess a good start would be around 5 ohms rated for at least 2 watts. This is what I use to knock 6 volts to 5.
Did you try just taking shorter drags?

[mcquinn]

ok thanx.It is hard to work ohms law if you only have E and no I or C. I suppose I could measure the resistance of the coil but amperage would be tricky to measure.

[Jim Davis]

Originally Posted by mcquinn

When I tried this I over amped the usb port on my work laptop,it reset when I rebooted but had me scared for a while.I went with the passthrough with the battery inline to smooth out the load.

My computers are too valuable to me. I always use a 110v to USB adapter plugged into the wall. It's easier to replace a blown adapter than have to replace a motherboard. My computer ports are for data only.

[mcquinn]

I agree now ,but the name usb passthrough to a Luddite means plug into computer usb port.They also extoll the vitues of using the passthrough for hours while typing at your computer.At your favorite forum I would suppose.I don't do cell phones.ipod's or any of the other little gadgets and was unaware that usb chargers were so prevalent.I did get a Janty pass through which has a battery inline and it does not draw on the puter so hard,I think the Joyes passthrough is the same judging by the photo's.If you want to make a usb power supply a 5 volt 1 amp wall wart will work and you can cut a usb extension cord in half red and black wires are for voltage use socket half on you power supply and the plug half on your home made passthrough.

[Jim Davis]

My homemade passthrough.
1-dead 4081 battery for the connector.
1-old USB cord.
1-2AAA battery box from Radio Shack - About $1.50.
1-3amp momentary button from Radio Shack - About 2 bucks.

Manual RN4081 Passthrough.jpg

[mcquinn]

Yours makes mine look like I tried too hard The copper would probably pay for a couple of factory builts

[Royal]

Originally Posted by mcquinn

Yours makes mine look like I tried too hard The copper would probably pay for a couple of factory builts

Dang!!! mcquinn, I give up, don't shoot!

Originally Posted by Jim Davis

My computers are too valuable to me. I always use a 110v to USB adapter plugged into the wall. It's easier to replace a blown adapter than have to replace a motherboard. My computer ports are for data only.

A lot of computers have built in protection which will shut down the USB 2.0 port should it overload the circuit. But I am with Jim on this one, I don't like taking chances.

Originally Posted by Jim Davis

My homemade passthrough.
1-dead 4081 battery for the connector.
1-old USB cord.
1-2AAA battery box from Radio Shack - About $1.50.
1-3amp momentary button from Radio Shack - About 2 bucks.

Attachment 14

Hey Jim, do you still have or know what the part number is for that 3 amp switch.

Here is a picture of my Prodigy with the modified switch. Just curious if it is the same switch.

[Jim Davis]

Sorry it took so long. I forgot about this thread.

SPST - Momentary Switch.
Radio Shack # 275-0644
Rated 3 amps @ 125v

[mcquinn]

here is my latest effort,I used a cell phone charger I bought from Goodwill for $1.99