I went ahead and ordered the charger kit i posted about above. I should get it in about a week. Ill post if it does anything interesting.

That's really creative. I was looking for an AC adapter that put out 2v 200ma when there's 4 perfectly good ones sitting right next to me in one convenient unit :) Smart idea with the fake AA! Now we can still use the built-in charge protection circuitry without taking out the battery.

That answers my Question #1. As for #2, please try this on a dual-cell setup if you have one and see if it will charge it too (though taking longer) or if you'd need like 2 fake AA's connected to one charging pad.

This thread is great...

One question I was wondering about...if that rayovac charger can handle this little soldiers, I was wondering if anyone has played with the idea of using one of those "smart" intelligent chargers out there. I have thought about trying one of those, but have been unable to find a good spec sheet on them, and the "details" for most of them out there say that they can handle 1200 maH AAA's. But if they're really "smart" and detect voltage drop (I think the IC most of them use is the Maxim 712/713 chip), then would they be able to detect such a drop on these sized batteries?

Never had dual cells, (too chicken about blowing my motor I guess) But I think you'd need to get the voltage from 2 AA charging bays if the peak charger is to work properly. The thing is you need a charger that is the type that wants to charge 2 cells at a time. You'd need to find the terminals that actually have the voltage on them.

I just tried a test on my energizer nimh charger, put 2 AA's in (real ones) and then measured voltage from one charge bay to the other. It was about 3.3 volts (the batts had some charge already). My charger takes 4 cells, but only in 2 sets of 2 (you'd be able to charge 2 cars with dual cells with it). Need 2 fake AA's (you'd put your wires on them where the charger reads about 3 volts)

I tried to measure without any batteries in the charger, but the voltage was really high (17 volts, with almost no current) -that could be bad for your car if the batts have a loose connection inside your car. The car's receiver probably doesn't draw enough current on it's own to bring the voltage down to the usual battery levels.

To be totally safe about that, I'd put a few LED's across the voltage output (3 in series should do)-- that way, if your batteries in the car have a momentary loose connection, the led's will light up and clip the voltage down to about 5-6V (depending on the type of led)
Under normal conditions, these led's wouldn't light from just 2.5 to 3.5v from normal battery charging or if they did, it would be very dim, and shouldnt affect the charging much.

Led's only begin to glow at 1.6V, and usually operate at 2.1v (approximately). The 3 led's would begin to glow if 4.8v or more was present.

Has anyone found out conclusively if the super brain is safe to use or not? It looks like it has a single cell charge mode that would work. If it is ok to use, does anyone have any test data of charge time vs run time?

I've been adjusting my charging rates, and I usually now charge at 300 ma to 500 ma. Typically this charges in about 20 minutes give or take and will run close to 2 hrs. I've charged up the car, ran it for about 20 minutes, let it sit overnight, and all the next day and driven for about 5-10 minutes the next night before recharging. I use the supernova 250 charger and use 150 NiMH cells. 2.2 motors and a variety of gears. Any of the smart chargers that can do NiMH (Or Nicad if you use them), peak detect, can charge down to 1 cell, and can charge down to .1 amp should be ok.

Results part 1 of ?
 

I built the charger that I posted about earlier. I finally figured out how to adjust the timing to about 5 mins. with the jumpers and pot. After an automatic discharge (nice feature) and two 5 min. charges on a stock LXX clone with a LXX 80 mAh NiMh cell @ 750 mA I set the stop watch and went at it. It drove for about 15 mins, better than ever, with no change in power seen. At 15-17 min it started to slightly lose power, and was performing as it would with a controller charge. It stayed suprisingly consistant till the 24 min mark, then just abruptly lost power for the next 30 secs till it was dead. Pretty impressive for some stock clone and a 20-something dollar charger kit. Ill try a 2 button cell 2.4v 70 mAh and a dual button cell 2.4v 180 mAh sleeper. I can fit a bunch of 70 mAh buttons, so mabye a 4 or 5 1.2v cell sleeper could be made up. Who knows?

Hey Ovgron, how were the instructions on assembling the kit? I am not an electrician, but can follow instructions. My wife says that I don't follow hers very well, but that is a whole different matter. Are you satisfied with your new charger or do you wish you had tried something different?

Where you getting the button cells? I take it they are rechargeable.

reply
 

http://www.allelectronics.com/cgi-bi...300&type=store <====Thats the batteries. Look on the bottom for the button packs.

The instructions were very complete. I have no complaints. Everything was i order. Even the resistors. They come in a ribbon that corresponds with the assembly order. No counting bands or anything. It was easy and took me about an hour, but i took my time. All I used was my 25 watt weller soldering iron, some 60/40 solder, and some end cutters (my leatherman was brought out a time or too, also). If anyones interested, ill post how i got 3 to 5 min charge time (rather than 1 or 14 hour) with it.

one thing...
 

it would be a lot nicer with an enclosure, and the proper 15 volt, 800 mA power supply.

Are you guys using your peak charger with the battery in the car and the PCB connected so that the charge would also go through the PCB in the car? If so are you doing this with multiple cells?

Thanks,
Kenny

battery CharGer
 

FWIW,

I use my DuraTrax Piranha Digital peak charger ($50) to charge my batteries. I set it for 100mAh capacity, and 200mA charge rate, 6mV peak detect. It takes about half an hour to charge the cell, and the car will run for well over 15 minutes with the red (2.6?) motor. I also installed a small on/off switch, so the battery doesn't drain down all the way when I'm not using it.
I had to cycle the cells a few times before I got close to the rated capacity (100mAh, and 80mAh). I used a #112 flashlight bulb as a discharger, the #112 is designed to run on 1.2V, it draws about 220mA, so it'll drain a cell in less than 30 minutes.
I guess I could bump up the charge current to charge them faster, but I figure the batteries will last a whole lot longer (more total charge cycles) with the lower charge current.

Thanks for the info. Are you charging the batteries while they are in the car so that the charge is also going through the PCB? If so are these dual cell cars or single? Does it matter if the peak charger goes through the PCB? It won't burn anything up will it? I have a Robbe Infinity II and will be peak charging my dual cell cars.

Thanks,
Kenny

I modded the controller so I can select the controllers internal charger, or an external charger. All it took was a Radio Shack SPDT switch and female coaxial power connector. The power jack is also how I connect the bulb discharger. I was thinking of mounting the flashlight bulb inside the Tx, so it can be used as an "emergency" flashlight when your helping someone else look for that lost steering spring. ;)

My mod will be able to charge a 2 cell (or more) BCG no problem, because it totally bypasses the internal circuitry.

Could you give us a pic of your controller. I notice that you got the Duratex is that from Hobbico? I was considering in picking one up. Why did you set it @ 6mV?

has anyone tried this with a dual 150mAH mod Zip?

As soon as the "holiday rush" is over, I'll post pix of the mod. Just getting through the holiday shopping, and picked up a Hot Wheels K.I.T. racer to use for parts. ($6 for a motor and battery, and maybe some other useful parts aint bad!)

Also, anyone know of a program I could use to illustate the schematics? (nothing expensive like PhotoShop, something less than $50 would be nice!)

dude, just download a demo of PhotoShop or download the whole thing......... there are all sorts of nameless ppl who just love nothing better than to give this stuff away....... just what i heard *wink wink*......l8r

I've been tempted to download some packages from Kazaa or WinMX, but I want to keep things legal. (I know, I'm a party poooper!) Heck, I'm still running Windoze 98! I do have a couple of PC's running Linux, because Linux is free - and most of the apps are free. Maybe I can find something suitable that will run in Linux.
Time to hit http://www.tucows.com!

Anyone know of any cheap solutions that will peak charge correctly?

so, really, u just need 2 nicads.
nimhs give so much runtime.
but do they give much more speed then nicads?

if i can get my scanner working or use webcam i can take pic of my two, 12 volt alkalines a stole from home depot

the alkalines are a milimeter taller than the stock battery and 12 volts and only cost like 99c for a pack of two

i dont think anyone is crazy enough to run 12 volts through their bit but they can get the batts from home depot and try

Well, I think that the 500 ma charge rate is pushing the limit with these small batteries. Some cells seem to handle it fine, but others have died on the first charge. I have ruined a few at that rate. Seems that 300 ma is safer, haven't fried any at that rate (yet).

Typical recommended charging rates are up to 2C. (which would be 100mA for a 50mAh cell, or 200mA for a 100mAh cell, and so on...)
Staying within these guidlines will give you hundreds of charge/discharge cycles. The built in charger really kicks these things in the butt with high current, so the cells typically only last a couple of hundred cycles. (the packaging on one of my clones states up to 300 charge cycles for the internal NiCd)

Rayovac creamed two of my cars
 

PLEASE HELP!

I thought I would try all these cool peak charged ideas.

First, I built one of the AC/DC chargers that uses a simple Radio Snack power supply that connects to a charging pad. It worked great at charging all my cars. The schematic was posted on one of these forums.

Having used the AC powerd charger I decided it was time to enter the big league and PEAK CHARGE my cars. I used alligator clips to hook up the Rayovac PS1 charger to a charging pad. Well, it PEAK CHARRED my cars! I only had them on the pad for about 40 seconds. Don't ask me why I did it to two cars :(

The end result was two cars that ran fine for a very very short period of time. Even when I charge them using the normal chargers they still poop out at about 1.5 minutes. I changed batteries in the cars but that didn't help. They are essentially useless now

My questions are:
- Do you have to take the batteries out of the car to use the Rayovac charger?
- How can I go about repairing my car? Do I need a new PCB?



I've learned from my lesson and am now using the cheap $9.99 cars from Walgreens for my experiments.

------------------------------------
Shen qi wei
Microsizers
Mega Toys
Zip Zap
b6way :btc: b38 b10 b26
b27m b35m b49m

ok......im not quite getting this?????? wats a peak charger first of all and if u r talking about the chargers that charge big r/c's i have one but i think the voltage is too high for it and i dunno how to do this anybody got like pictures???? of how to do this and wat i need to do this

A peak charger measures the voltage while charging a battery, when the battery is fully charged, the voltage actually drops a tiny bit, the charger stops when it detects this.

If you keep charging a battery past full charge, it gets wasted as heat, which can eventually fry the battery.

If you have a digital meter, you can watch the voltage slowly climb for most of the charge time, then the last few minutes it will climb much faster, untill it hits the peak, and then drops back a tiny bit.

I'm going Lithium.
If anyone wants a set of plans for a good Li-Ion/Li-Po peak charger, just ask. I'm going to use my beloved Apache 1-2 cell, if I can just find where I put the stupid battery....
The advantage of Li-Ion over 3 200mah -cells:
-Cheaper (2 li-ions for 6.00 (1=3 NiMh), a 200mah is usually about 5.00)
-Slightly faster (the Li-Po puts out 1/36 more voltage, with a WAYY flatter discharge curve)
-FAR HIGHER CAPACITY (can anyone say 800 MAH! That's a long runtime!)
P.S. if someone knows of a small Li-Ion battery, let me know. I intend to mount mine on the top, and simply make a ugly car. If I could find one that would work internally, that would be nice.

i understandink nows
 

I finally think I understand this peak charger thingy...
Now, do you get a battery charger and then you put your battery from your cars into the charger(so it fits of course) then charge it like any old battery, so then your battery can get a full 15 minute charge without going it bung or exploding, and with some of you guys, you have bought ones that you can attach your controller pad to so you can charge your batteries in the charger without actually having to take the batteries out.:rolleyes:
if this is right i need to know 2 things, this has to be in ultra laymans terms when you reply, how many batteries can you fit into a aaa battery slot on a charger so you can char-g a heap at once and if you are wanting to attach a controller charging pad to a charger do you just get some wiresand attach them from the pad to the charging output thingies. oh and one last thing, what voltage and amp levels does your charger have to be

I got a sweet duratrax intellipeak setup that I will use to charge my bit, not to mention I have 1800+ mah nimh AA's for the controller. I can't wait to get the upgrade nimh for by bit.

http://www.universalhost.de/html_bit/b-charger.htm

this is the cheapest way I beleive... You can even get 2 free samples of MAX 713 chips at http://www.maxim-ic.com/

cool fast and simple

hi, i recently made my super bit charg dual cell, but after i charge it everytime (i use a piranha peak charger at .3 A) the bit stops working, then if i wait for a while(about an hour) or i desolder the batteries and put it back in, it starts working again can someone tell me why? i'm sure its not due to a loose connection that causes it to stop working as the solder joints i put on it were pretty strong and nothing has been disconnected

You may be putting too much voltage to the circuit board during the charge, causing the circuit to cut out (i think they have over voltage protection). When you remove the battery, it allows the circuit to reset. This may or may not be the problem, but sounds like it could be. I like to put a small switch between the batteries and the circuit board on multi cell cars, to avoid this problem. Also, you can try making the battery connection to the charger before powering up the charger. I know my Tekin peak charger will give a surge over 20 volts if it is powered up before plugging in the battery.

ok, i'll try putting in a switch then, thanks!

I just peak charged my clone with my charger I set it to 500ma under nicad and said the battery was up to 100mah with a 6mv sencitivity I topped off at 98mah its a charge n go clone I thought it was a nicad battery but with that amount maby it wasnt does anyone know the specifications on the battery?
Nick

So i could get an old controller and put my losi peak charger on (From my mini-t). Could i use a connector on the controller to make hook up a snap. This with the 150mah NiHm would be great. Also, how easy is this to do and were can i get an extra controller.

Anyone try a Triton Charger???
 

Has anyone tried this with a Triton charger?

I am trying to cycle my 1/4 AAA 150 maH batteries I picked up, and it seems like it can't detect the peak.

Just curious...

Eric