azmax100, check your inbox. I sent you a PM about trading arduino with ICD2 LE. Let me know if you are interested. Thanks.

I've PM you.

hey guys....i wanted to ask...where do i find a basic led circuit...i dont need any flashing type or watsoever....just a plain led circuit...got 2 criteria

1. the led must remain lit without blinking or anything else
2. i'm using alot of leds...nearly 100 of em...so is there any way to connect to
a 240v power supply cause i think battery not enough to keep it lit for long ...its something like christmas lights

Hi gurus, I need help in getting battery. I have a portable memory card reader with an internal battery that is dying. THe dealer that i got it from says they dont import the replacement battery. I am contacting the manufacturer but i highly doubt they will sell it to me personally. So I am trying to source it here in KL.

Product Website: Nexto M1

Picture of the Battery in question attached.

On the website the battery suppose to be: Internal battery : Li-Poly (3.7V, 1550mAh)

Dimension of the battery is 6mm x 40mm (wide) x 60mm (long)

There is no other marking on the battery as to the voltage or capacity which is usually suppose to be there.

Is there any place to get these kind of battery? Jalan Pasar got? Know roughly what is the price? thanks



Edit: Figured out that the code PL-654060 is actually the dimensions of 6.5 x 40 x60mm previously i measured with ruler

This post has been edited by FLu_Shots: Sep 26 2009, 12:29 PM


Attached thumbnail(s)

custom using the likes of this?



http://cgi.ebay.co.uk/1550mAH-Battery-For-...915136003r26115

wow a really need to hack it if i am going to use that... is that a battery for the nokia E90?
I see some chinese(china) manufacturers making the exact same one as in the picture i attached. I am hoping to get the exact same that looks the same. somehting like this
Li-Poly Battery

This post has been edited by FLu_Shots: Sep 26 2009, 06:14 PM

You can use any Lipo battery in the market, provided that it is rated for 3.7v. Lipo single cell voltage is 3.7v, that means there is only a handful of lipo battery with voltage of 3.7v, 7.4v, 11.1v etc, so don't worry if you get an off-spec battery.

The mAh is the capacity, the higher the number, the longer it can be put in service and vice-versa. You application probably drain only a few mA, other lipo specification is not important. If you can't find 1550mAh, you can use any rating, it won't affect your device.

So, you can just go to any handphone or camera shop, and show them the battery and say you want the battery which has the exact same size.

One last thing, all single cell lipo after fully charge is rated at 4.2v, therefore you may find certain lipo battery rated at 4.2v, instead of 3.7v. Don't worry, you can use it. Your device would automatically cut-off the charging when it reach the appropriate voltage.

This post has been edited by Aurora: Sep 27 2009, 01:03 PM

Hi thanks for the reply. I already know the requirements for the battery actually. I am looking for specifically the battery with the wire leads as installed in the unit right now. I also know that a normal handphone or camera shop while they have Li-Poly batteries are not as the one I have posted. Actually I just need to know where I can buy the Li-Poly cells like the one I posted. I will try Jln Pasar this coming week but would appreciate any recommendation to anywhere else which I buy them from. Thanks

This post has been edited by FLu_Shots: Sep 27 2009, 04:19 PM

Last I checked RS online got sell several Li-Ion battery. Not sure about Li-Po.

Or try those Radio Control hobbyist shops. Like this ->RC Battery. Generally RC use larger size battery 7.2v and above, but this shop seems to have a couple of 3.7v choices albeit with smaller current capacity.

Actually I'd advise you to only replace with similar size battery (both voltage and current capacity), and to only get them from reputable sources. I'm somewhat concerned about replacing the battery pack with a smaller or larger unit, as I don't know how your battery charger circuitry works.

Noted with thanks. I am actually limited in space in the casing anyway and from what i have seen Li-Poly capacity are very size dependent. The larger they are the higher the capacity. That said, I have also been reading some datasheets for some IC chips for Li-Ion and Li-Poly recharging they all are charged by monitoring the voltage across the batts. Have not heard any concerns regarding charging rates though. Any thoughts?

I believe the really good chargers use a combination of timing, voltage and current monitoring, as well as over voltage and over heat protection.

Since your equipment is not a battery charger, it's most probably designed to suit a particular battery capacity only. E.g. it's timer may be hard-coded to charge a 1550mAh battery. In this case, if you try to charge a larger battery it won't ever be fully charged as it would timeout first.

And some "cheaper" product might get away by using very simple solution with very little or no protection. These would be very dangerous to use on a smaller battery.

BUT, these are all just my views only, I'm certainly no expert in battery and charger design
If you're good and careful enough, you'll survive la

Want to ask, anyone knows if any simple room temperature sensor that connect to PC USB or DB-9 ? Also comes with simple software that interface with it to provide room temperature.

Range: 0-60 Celsius
Incremental in 0.5-1.0 is enough

To properly charge a Lipo, it need a built-in charger circuit, which monitor the peak voltage. Charging lipo without proper monitoring is extremely dangerous, it may cause fire and explosion. And because it monitor peak voltage, they automatically cutoff when it reach peak voltage. It's safe to say that you may charge any mAh lipo, provided they have the same voltage rating. Normally the only concern for Lipo charging of the same voltage is its charging ampere. For your device, it should be relatively low, USB support relatively small current. USB devices with battery are normally smart charging circuit, not time-counter circuit. This is due to reason that the design take into account of frequent and inconsistent plug and play of USB device, hence the circuit need to be smart.

I forget to mention that you can get it from any RC store (as tgrrr point out). You can try asking in RC forum. As far I know, lipo can be custom made, rcsmart do offer custom made size and capacity, but with condition of minimum order of 5, I think. Not that I encourage you to customize ur battery , but they have more selection and you can get it from them. Another great site is HobbyKing. HK-base company, relatively cheap courier delivery cost.

You can try instructables, or try Jalan Pasar, I think I saw a kit or something similar, with LCD, temperature sensor, cooling fan. It's either by cytron or bizchip. With a bit tweak, you can interface with PC via DB-9 (or RS232). If you want a complete solution, I can do it for you, with a small price.

This post has been edited by Aurora: Oct 1 2009, 11:16 PM

You can do it with PIC or Arduino. Do And learn at the same time.

It's so simple. Using temp sensor connect to analog port. A little bit programming then you have it.

The best part you can be proud of yourself.

BTW you can look at the data from serial monitor if you are using Arduino.

This post has been edited by azmax100: Oct 6 2009, 12:42 AM

here is non-technical ques

how many of u are enthusiasts here? rather jz bcoz to develop ur sch/uni projects?

I'm a bit enthusiasts. Not for uni/school. Is for my own personal project. No monetary/reward/certificate/returns.

It's my hobby and also part-time.
My main job of firmware programming is also related.

Hobby,enthusiast and try helping others too.

For me this is a challenging hobby where you have to combine your skill and knowledge.

The results?

It may be frustrating sometime but the success story worth more.

This post has been edited by azmax100: Oct 7 2009, 06:21 PM

As a pastime hobby, seeking personal satisfaction.

Shall we organise a TT?

TT?

Tech Team.

Tools Time.

Tik Tok.