HOW TO Make A USB Passthrough

[auraslip]

Another thing you can do - that I've done - is to put 2 or more cell phone chargers in parallel. That is, I've connected the outputs of two 1a chargers to make a 2a charger. Then I attach a female usb plug or a usb hub to it. This is actually really awesome because it charges my normal ego-t battery and my cell phone much faster. Less voltage drop = faster charging

The problem with this though is that you won't get any voltage drop - the atty will see a full 5v - and with a 1.2 ohms atty that means it'll be running at 4a and dissapating almost 20w of heat.

That's gonna burn the atty out real quick. I'm thinking using an LED or two to drop the voltage would be ideal here. Can a normal LED handle 2a?

Second question - Am I to understand that shorting the data lines of a usb cable attached to a computer will allow it to pull more than 100mah?

 

[WillyB]

Another thing you can do - that I've done - is to put 2 or more cell phone chargers in parallel. That is, I've connected the outputs of two 1a chargers to make a 2a charger.

....This is actually really awesome because it charges my normal ego-t battery and my cell phone much faster. Less voltage drop = faster charging

The problem with this though is that you won't get any voltage drop - the atty will see a full 5v - and with a 1.2 ohms atty that means it'll be running at 4a and dissapating almost 20w of heat.

Something don't make sense here. You say "two 1a chargers to make a 2a charger", I use 2A power supplies and never see 5V with any of my Joye atties.

Then you say "with a 1.2 ohms atty that means it'll be running at 4a". How did the original 2A now become 4A?????

Have you ever done any actual loaded volts tests?

 

[Rocketman]

Another thing you can do - that I've done - is to put 2 or more cell phone chargers in parallel. That is, I've connected the outputs of two 1a chargers to make a 2a charger. Then I attach a female usb plug or a usb hub to it. This is actually really awesome because it charges my normal ego-t battery and my cell phone much faster. Less voltage drop = faster charging

The problem with this though is that you won't get any voltage drop - the atty will see a full 5v - and with a 1.2 ohms atty that means it'll be running at 4a and dissapating almost 20w of heat.

That's gonna burn the atty out real quick. I'm thinking using an LED or two to drop the voltage would be ideal here. Can a normal LED handle 2a?

Second question - Am I to understand that shorting the data lines of a usb cable attached to a computer will allow it to pull more than 100mah?

Running a couple of 1 amp chargers in parallel (2 or more? how many more?) will probably overheat the chargers. Most LEDs will burn out at about 30ma and drop 2 to 3 volts (depending on color). THe 5 volts going in (which the 2A charger would not produce) would be dropped to 2 to 3 volts by the LEDs (if you paralleled about 100 of them.

Sorry but a little ohm law practice might be in order here.

20 watts?

 

[Rocketman]

Running a couple of 1 amp chargers in parallel (2 or more? how many more?) will probably overheat the chargers. Most LEDs will burn out at about 30ma and drop 2 to 3 volts (depending on color). THe 5 volts going in (which the 2A charger would not produce) would be dropped to 2 to 3 volts by the LEDs (if you paralleled about 100 of them.

Sorry but a little ohm law practice might be in order here.

20 watts?

Someone needs to put this to bed. I don't do 5 volt vaping, so any "pass Through" I use "charges a battery" with a lot less than 1 amp. I then vape off the battery, at a lot more than 1 amp.

To vape at 5 volts with a direct wired pass through you absolutely need more than you can safely get from a computer USB jack, or a powered hub, or one or two little power supplies. If you overload the wrong type of supply and it is connected to the 115VAC outlet and the other end in your mouth (steel carto on a home made pass through) you are asking for toe tingling electrical shocks

Please don't offer unqualified advice on how to do something because someone will try it. Post something that has been show to actually work. There are 5 volt switching supplies that would work. Hefty wiring and a good switch (mechanical or mosfet) could easily be used to vape at 5 volts with a home made pass through.


Maybe someone can post a good DIY on how to make a good 5 volt pass though before this gets to post 100

Ya think?

 

[auraslip]

Then you say "with a 1.2 ohms atty that means it'll be running at 4a". How did the original 2A now become 4A???

Err. What I meant was that if you had a 5v power supply that could deliver the power you need, according to ohms law it would deliver 4a.

 

[Rocketman]

auraslip,
you're correct.
I think we are jumping in here because a lot of folks are mislead by vendor claims about "pass throughs".
How many times have you seen one advertised that would have a hard time delivering 5 volts because of a thin cheap cord? A cord that usually opene and quits working, or shorts and messes up the supply (hopefully not a laptop). It's tough to get 5 volts all the way out to the end of a PT cord.

It's a neat idea, being able to vape all day while sitting in front of the computer and not having to get up to swap batteries, but very few actually work well. Now with all the rave being low resistance, Pass Thoughs are even harder to come up with that will work with these (LR being anything under 2.0 ohms). People tend to get all wrapped up in hype. 5 volts is the craze, you know, the "SWEET SPOT" and now Low Resistance is on everyone lips.

So, you got pounced on when you said the words "Pass Through". Hang in there and keep on modding.

Rocket