My 1st mod resistor question

[kwalka]

The following pic/schematic is a copy of SteelJan's basic box mod layout. She calls for a 470 ohm resistor. I only have on hand a 330 and a 150. Can I use these 2 in series in place of the one 470 the schematic calls for? FTR, I am using an 18650 batt. and a 2 ohm atty. If any of you are extremely impressed with the photo, just ask and I will share my very high end CAD software.

 

[Java_Az]

just use the 330 ohm resistor it will be fine. It will be just a tad bit brighter then using a 470ohm

 

[kwalka]

Thank you ........

 

[alexp843]

just dont put the battery in backwards......instead of having the led light it will suck all the light out of the room and you wont see anything

 

[DonG]

The following pic/schematic is a copy of SteelJan's basic box mod layout. She calls for a 470 ohm resistor. I only have on hand a 330 and a 150. Can I use these 2 in series in place of the one 470 the schematic calls for? FTR, I am using an 18650 batt. and a 2 ohm atty. If any of you are extremely impressed with the photo, just ask and I will share my very high end CAD software.

View attachment 104252

Dont forget to add your switch.

 

[kwalka]

Dont forget to add your switch.

Oh yes the switch is just to the right of the word batt. Luckily my actual schematic reflects your recommendation. My CAD program is so involved that during the execution of the drawing it was inadvertently omitted. Thanks for the heads up.

 

[kwalka]

just dont put the battery in backwards......instead of having the led light it will suck all the light out of the room and you wont see anything

Yes, again great advice. I feel welcomed into the mod community. In all seriousness I label all my batts toward the positive pole as to avoid said incident.

 

[slimest]

Different LEDs have different brightness with the same resistor in series. You can begin with 330 ohm, then, if LED is too bright, add another resistor. Or, if brightness is too low, use less resistance.

 

[kwalka]

I was reading a modding thread where they were doing math calculations to figure out the resistance neededs to get the desired amount of voltage/amperage to the atty. What is the difference between using a resistor to control the brightness of a LED vs using one to control voltage/wattage?

 

[been there]

That's a good question kwalka and I was wondering the same thing because I sure as hell don't want to suck all the light out of the room.

 

[kwalka]

Here is the link to the thread in question.
http://www.e-cigarette-forum.com/forum/modding-forum/31339-battery-resistance-calculations.html

This applies to post #9 here.

 

[asdaq]

Actually with the lower voltages we use and the further use of resistors, the LED just won't light but not be damaged. This can be useful for stealth vaping, say in the cinema.

 

[kwalka]

Ok, but are we controlling the brightness of the LED or the voltage getting to the atty, with resistors?

 

[asdaq]

With the LED wired in parallel to the atty, the resistor is limiting the current to the LED and not the atty, if it were in series (not what you want to do) it would limit the atty too. It does complicate the overall circuit and take away from battery life and a tiny fraction of the voltage going to the atty, but nothing really noticeable.

 

[kwalka]

Ok keep in mind Im a pretty fart smeller, but your losing me with the difference between Parallel vs series. In my diagram in post #1 it seems to me the resistor, the whole thing for that matter, is 1 circuit. WTS, how is the resistor not effecting the atty and the LED, given that their both the same circuit?

Smart Feller

 

[asdaq]

By parallel, it is added to the simple circuit of the battery, switch and atty. If you remove the LED part, it still works. If it were in series, it would interrupt the flow of current and would not work if removed. You'd have two loose wires that need to be need to be attached to complete the circuit. The battery is supplying current to the atty and the LED is 'tapping in' to this supply.

A bit like the car stereo, the car still drives with the music off, it's just not as fun.

 

[kwalka]

Yes! Now your speaking my language. Well,guess what? I just vaped on my new 3.7v box mod. And I didn't light up the room. I will take some pics before I fill the whole thing in w glue. I'm interested to get your take on the setup.

 

[asdaq]

Car analogies can have that effect.

Enjoy your new mod, maybe don't fill it with glue even.

 

[slimest]

I was reading a modding thread where they were doing math calculations to figure out the resistance neededs to get the desired amount of voltage/amperage to the atty. What is the difference between using a resistor to control the brightness of a LED vs using one to control voltage/wattage?

Difference is that a LED is not a heater. Different LEDs have different effectiveness. Say, if I use an usual indicator LED, I consider working current about 10 ma, and its brightness is just acceptable to see. But if I use for example high efficiency green LED in one of my mods, I found out that it is too bright even with current about 1 ma. Do you feel the difference? Approx ten times.
I used this green LED: http://dx.com/p/8000-mcd-5mm-green-led-emitters-10-pack-9076?item=22

 

[kwalka]

Difference is that a LED is not a heater. Different LEDs have different effectiveness. Say, if I use an usual indicator LED, I consider working current about 10 ma, and its brightness is just acceptable to see. But if I use for example high efficiency green LED in one of my mods, I found out that it is too bright even with current about 1 ma. Do you feel the difference? Approx ten times.
I used this green LED: 8000+ mcd 5mm Green LED Emitters (10-Pack) - Worldwide Free Shipping - DX

I'm kind of following you, but I still dont see how w/o having a second, isolated circuit, the resistor is not affecting both the led and atty, as they are both on the same circuit. Does that make sense?