Running on Rechargeable Batteries
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Running on Rechargeable Batteries
If you plan to run the spoke pov's solely on rechargeable batteries, what adjustments needs to be made? I'm also trying to get the current as close to 20 amps as possible. Please keep in mind that this is the first time I've ever put together a PCB board. Thank you to anyone who can give some advice.
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How to short resistor packs?
How would one go about shorting the resistor packs, and would this be a permanent solution?Install the resistor packs provided, then short them to see if you like what you see.
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The resistor packs have one pin that is the common. In this circuit it is connected to the positive supply. If you connect all the pins together on the solder side of the board then you have in effect connected the anode of the LEDs directly to the positive supply bypassing whatever current limiting effect the resistor packs previously have had.
Regarding the permanence, this doesn't harm the resistor packs, in fact in this condition they dissipate no power. When you take off the bridging of the pins, the resistor packs will operate in their original intended manner.
You should keep in mind, if you mistakenly load in regular 1.5V batteries in after you've done this mod to boost the current for rechargables, you might overdrive the LEDs.
Regarding the permanence, this doesn't harm the resistor packs, in fact in this condition they dissipate no power. When you take off the bridging of the pins, the resistor packs will operate in their original intended manner.
You should keep in mind, if you mistakenly load in regular 1.5V batteries in after you've done this mod to boost the current for rechargables, you might overdrive the LEDs.
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- Joined: Wed Oct 03, 2007 7:17 pm
So in order to acheive around 20 mA using rechargeables would you have to buy anything that is not provided with the kit? Because you can get many different types of RN1-RN8 to achieve different ohm. There are two kinds of resistors. The R1 and the RN1-RN8. Do you have to short both types of resistors or just the (RN1-RN8)? Also, by shorting them do you mean that the pins are only touching/soldered onto the solder side without being connected to the reverse side. How much mAh should the rechargeables have? As much as possible?kayrock66 wrote:The resistor packs have one pin that is the common. In this circuit it is connected to the positive supply. If you connect all the pins together on the solder side of the board then you have in effect connected the anode of the LEDs directly to the positive supply bypassing whatever current limiting effect the resistor packs previously have had.
Regarding the permanence, this doesn't harm the resistor packs, in fact in this condition they dissipate no power. When you take off the bridging of the pins, the resistor packs will operate in their original intended manner.
You should keep in mind, if you mistakenly load in regular 1.5V batteries in after you've done this mod to boost the current for rechargables, you might overdrive the LEDs.
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- Joined: Thu Apr 06, 2006 4:21 pm
for any LED color, 22 ohm resistor packs will be as good as you can get. there's no way to get 20 ma per LED since its current limited at the 595's at something like 5-10mA
the SMALLER THE RESISTOR PACKS, the HIGHER THE CURRECT thus BRIGHTER LEDS
HOWEVER, DO NOT short out the resistor pack, its not good for the 595 latches.
i would use 22 ohm resistor packs, any lower and you could could damage the latches.
the SMALLER THE RESISTOR PACKS, the HIGHER THE CURRECT thus BRIGHTER LEDS
HOWEVER, DO NOT short out the resistor pack, its not good for the 595 latches.
i would use 22 ohm resistor packs, any lower and you could could damage the latches.
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- Joined: Wed Oct 03, 2007 7:17 pm
Here is the spec sheet on the latches:ladyada wrote:for any LED color, 22 ohm resistor packs will be as good as you can get. there's no way to get 20 ma per LED since its current limited at the 595's at something like 5-10mA
the SMALLER THE RESISTOR PACKS, the HIGHER THE CURRECT thus BRIGHTER LEDS
HOWEVER, DO NOT short out the resistor pack, its not good for the 595 latches.
i would use 22 ohm resistor packs, any lower and you could could damage the latches.
http://focus.ti.com/lit/ds/symlink/sn74hc595.pdf
Are you sure the mA has to be that low?
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i post saying "the max current is 5-10mA"bikefreak wrote:Here is the spec sheet on the latches:ladyada wrote:for any LED color, 22 ohm resistor packs will be as good as you can get. there's no way to get 20 ma per LED since its current limited at the 595's at something like 5-10mA
the SMALLER THE RESISTOR PACKS, the HIGHER THE CURRECT thus BRIGHTER LEDS
HOWEVER, DO NOT short out the resistor pack, its not good for the 595 latches.
i would use 22 ohm resistor packs, any lower and you could could damage the latches.
http://focus.ti.com/lit/ds/symlink/sn74hc595.pdf
Are you sure the mA has to be that low?
you read the datasheet, it says 6mA.
why are you posting questions that have been answered twice?
do you just enjoy posting to this forum?
I mean. at this point im just getting frustrated. this forum is primarily here for me to offer tech support to people who have gone ahead and built the kit and need assistance getting it working.
personally, i can't take you step by step thru your project anymore, especially with all the posts and emails youve been sending. i have thousands of customers. i wish you luck, but i strongly suggest hiring someone who has the time to do this for you as i simply cant offer this level of hand-holding support!
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- Joined: Wed Oct 03, 2007 7:17 pm
I know what you posted. I just wanted to make sure because I'm not familar with this techno mumbo jumbo. I'll keep in mind what you said about this being for those who've already built it but I always thought this was a place where people can discuss the spokepov, not just a one on one chat. I've sent several e-mails in total but perhaps my posting on these forums has you thinking I'm everywhere. I was just trying to help myself and others to do some mods. Certainley I'm not the only one who is technically deficient and eager to do the same things as I.ladyada wrote:i post saying "the max current is 5-10mA"bikefreak wrote:ladyada wrote:for any LED color, 22 ohm resistor packs will be as good as you can get. there's no way to get 20 ma per LED since its current limited at the 595's at something like 5-10mA
the SMALLER THE RESISTOR PACKS, the HIGHER THE CURRECT thus BRIGHTER LEDS
HOWEVER, DO NOT short out the resistor pack, its not good for the 595 latches.
i would use 22 ohm resistor packs, any lower and you could could damage the latches.
Here is the spec sheet on the latches:
http://focus.ti.com/lit/ds/symlink/sn74hc595.pdf
Are you sure the mA has to be that low?
you read the datasheet, it says 6mA.
why are you posting questions that have been answered twice?
do you just enjoy posting to this forum?
I mean. at this point im just getting frustrated. this forum is primarily here for me to offer tech support to people who have gone ahead and built the kit and need assistance getting it working.
personally, i can't take you step by step thru your project anymore, especially with all the posts and emails youve been sending. i have thousands of customers. i wish you luck, but i strongly suggest hiring someone who has the time to do this for you as i simply cant offer this level of hand-holding support!
Last edited by bikefreak on Sat Jan 05, 2008 5:35 pm, edited 1 time in total.
Please be positive and constructive with your questions and comments.