Car wont move

[HACHI-RYOKU]

Hello. This is my first post here, but I’m not new to R/C.

I recently took a zip-zap and put 4 little 1.2 volt digi-q batts inside it. So it’s a quad cell. Then I took a bit pcb that I fet modded and installed that. I thought it would make a beast of a car, but while the quad cell zip worked with the zip-zap pcb, it wouldn’t even bugde with the fet modded bit pcb. The fet modded pcb does work on the single or dual cell bits, just not in the zip-zap. Any body else run into this problem?
The strangest thing though, It will twich a little if I run another car on the same frequency.
I think the voltage is too high (4 x 1.2 volt batts in series = 4.8 volts). I’m probably gonna try puting three of those batts inside a bit instead of 4 in a zip. I like those batts though. They are smaller than regular bit batts, so you can fit more into a car. I fit 4 inside a zip-zap! I should be able to get 3 in a bit.
In case anybody was wondering, I got them from digi-q cars. I’ve also seen them in the new ZZSE and the new cars from Tyco. All three of these are dual celled cars. I wouldn’t recomend buying the cars just for the batteries unless they are on sale. I picked up two digi-q cars (no controllers, just boosters) from a toys r us that was having a clearence sale, because they were moving to another location. Each car was $4.50.

[micro_Amps]

Yes, the voltage is too high.
I think I recognise this topic from somewhere else.
Greetings to you in Japan, BW :smiley2:
:)uA

[leonli17]

Most likely the batteries are 1/4 AAAs.
uA: i thought the Bit PCBs can handle 6V, y can’t it move when it’s only 4.8V?

[Impreza]

1/4 AAA’s? does ne1 have pics of these bats? This has been discussed b4 and I don’t remember there being too much of a size dif between 1/4 and 1/3’s:( small washer width is all. Will have to check.

Edited by – Impreza on 06 November 2003 01:52:29

[HACHI-RYOKU]

Yeah, I thought it could handle 6 volts too, but appearently not. Although the last time I heard that they could handle 6 volts, I think it was coming from someone without a fet modded board. It will be a couple days until I tinker with it some more. I’m gonna try a super bit pcb and maybe a different fet modded bit pcb to see if it was just that one pcb.

The digi-q batts(1/4aaa?) are roughly 3/4 the size of the bit batts. I don’t know if the gain will be all that much because they probably have a lower current, witch I think will effect the cars ability to reach it’s top end speed.

I just remembered something stupid!!! The pcb comes from a cyclona, not a bit. Maybe the cyclona pcbs can’t handle that voltage. I’ll try a bit modded pcb next.

By the way, thanx for the welcome. I’m happy to be here.

Edited by – HACHI-RYOKU on 06 November 2003 09:04:51

[titaniumonkey]

wow…4 cells…that’s a whole lot of power.
BTW, greetings to you in Japan

[jamiekulhanek]

As far as i *knew* the bit PCB can handle 5v (normal logic level)

[VooDooMafia]

I thought the se cells ere different form teh digi Q cells?

[jamiekulhanek]

All the same voltage 🙂

[HACHI-RYOKU]

I never really did a close inspection of them. I just noticed that there were two small batts in series that were nimh. They were a little smaller than regular bit batts. Probably the same as the digi-q’s.

[micro_Amps]

BCGs use 1/3 AAA cells that are about 13mm x 10mm
Some of the two cell cars use 2 x 1/4AAA cells that are 10mm x 10mm.
These include, the enertec cars, the Digis, micro machines and others.
Most have them sitting side by side. The NiMh 1/4AAA cells are 70mAh (GP7AAAH) and run well if they are peak charged. Maximum output current is less than the 1/3AAA cells but still more than enough to run a micro motor.
:)uA

Edited by – micro_Amps on 06 November 2003 23:32:13

[Impreza]

thnx for clearing that up u. The bats in the zz se must be laid in front to back? Actually that brings up an off topic question. Are dual cell cars wired in series or parrallel?:blush:sorry never done a dual cell b4:shy:, but will do one soon:)

[micro_Amps]

The ZZ SEs have the two in a line, in roughly the same position as a BCG battery.
Imprez a dual cell has the extra cell put in series with the original cell to double the voltage to the motor.
:)uA

[Impreza]

thanks micro. Will soon try the dual cell mod. One more question on the se. If the 1/4 AAA is the size that I think it is how do you fit 2 in the se roughly where the bit bat goes. Heading south tomorrow.. may have to pic one of these up (mainly out of shear intrest now:)

[HACHI-RYOKU]

The 1/4aaa is pretty small, plus the ZZSE’s internal compartments have a little more room to fit all kinds of stuff. Although, it already comes packed tight with components. I can’t see anybody internally modding this car much more. Hopefully, I’m proven wrong.

Impreza, I would only recomend getting a ZZSE if you plan on fet modding it. Microamps is doing the fet modding for it also, if you want to send him the car. Otherwise, the speed is rather disappointing. It runs like a 1.0~2.0 (without the torque) even with the good motors.

[Impreza]

I would guess so with all the stuff packed into this thing:shock: Must weigh a bit too?

[HACHI-RYOKU]

Yeah, they are heavy. I would like to know what I can rip out for weight reduction.

[micro_Amps]

I dont think there is any ‘extras’ in there that can be removed. Its all needed for the car to run properly.
Maybe (I havent tried this) removing the cells and replacing it with a LiPoly cell, which is half the weight and 50% higher voltage would see the thing screaming, but it is probably easier to just fet mod it and get the performance increase that way.
:)uA

[HACHI-RYOKU]

Well, I’ve been a ghost for a while. Sorry, I haven’t been neglecting the mod, I’ve just been busy. I just got married to my wonderfull seductress. Needless to say, I haven’t had much time on the computer. I have been keeping at the mod though.
So far I have one pcb that the car fried, and a score of others that just didn’t work. The fried pcb is fixable. I just need to replace the steering transistor.
Most of the pcbs have the same symptoms. Some functions work, but others don’t. For example, the forward works, but not the reverse. Or the same with steering, right works, but not left. I know it’s not my soldering skills either. So I have a feeling 4 x 1.2volts in series is just to much for mosfeted pcbs. I’m going to keep trying even though I’ve about lost patience. My next pcb will probably come from the type III super perfection cars. Anybody have one and think this is a bad idea? Mine hasn’t come in the mail yet.

[betty.k]

sounds like a problem i had with another pcb. i only doubled the voltage and poof! that telltale wisp of smoke! there’s a way to do it but man, 4 cells is nuts! how you gonna keep it in a straight line?!:shock:
oh and congrats on the knot tyin’ festival!:8ball:

Edited by – betty.k on 08 December 2003 21:14:54

[micro_Amps]

every electronic component has a wisp of smoke inside it, its only when the component releases that little bit of smoke that it stops working.
:)uA

[Impreza]

H-R, congrats on the wedding. I have no advice atm but would love to see pics of your work.

[HACHI-RYOKU]

Thanx everyone.

About the straight line thing. I’ll just have to worry about that when I get to it. First I gotta get the car running. I know it will be difficult, if not impossible. I use alot of duall cell/fet modded cars and I can tell you they take a lot of tweaking to get it to run straight and then some more to keep it that way. But I have learned that the lower gear ratios will help. A duall cell/ fetted car is almost impossible to get straight acceleration with 9:1 gears. Now take that car and throw on the 3:1. It will run much smoother, as well as you’ll turn all that extra torque into speed. Who knows,.. Maybe with 4 cells and a fetted board it will take a 1:1 gearing. Gotta learn how to make one of those first though.

I’ll see if I can’t get some pictures up tonight.

Edited by – HACHI-RYOKU on 09 December 2003 14:32:15

[HACHI-RYOKU]

Took me a little while, but I figured out how to get my pics on the forum. I’m a bit of a knuckle-head on a computer.

[leonli17]

Just watch out for ur motor H-R. Because now u have 6V go through the motor. And it will be really easy to stuff the motor. So don’t run the car too long.
And u’ll need a really big space to let it reach top speed. I think about 20-30M. Because remember u got 4 cells on it. All the extra weight will reduce the acceleration.

[HACHI-RYOKU]

Not with the mosfet modded board. It’s got much more torque than the average duck. I haven’t put a low gear ratio in yet.

I’ve already done some test for speed. Nothing major, but it has no problem taking off. Also, it’s only 4.8 volts (1.2 x 4 = 4.8). Thanx for the warning though.

With the dual cell/fet modded bit, it takes about a 1~2 feet (maybe less) to go from 0 to top speed, IF you have the stock 8:1 gears.

[betty.k]

man i wanna be there when this thing goes, it’s either going to succeed really well or die in an exciting way! you may get to see lots of smoke!:p:8ball:

[HACHI-RYOKU]

I picked up a digital speed checker and some straight track (to keep it going straight) for test runs…….when it works………if it works.:sad:

I guess if it goes up in smoke, then that would be cool too.:evil:

[HACHI-RYOKU]

It works!! I’m having problems charging it though. Nothing I have will properly charge it. I also don’t have a peak charger. Anybody have any quick and easy ideas. I tried a wall-mount with selectable voltage. It’s rated at 300ma, and can select any voltage 1.5~12 in incriments of 1.5.
If I do the math, then; 4 x 1.2 volt, 110mah batts = 4.8 volts, 110mah.
If I want a good charge I will need to select 4.5 volts at 300ma, right?
For time to charge; Then 110/300=.36 + 20%= about .43hours. Or about 26 minutes.
Well, when I put it on the charger the pcb gets extremely hot. Why???!!!
If I set the voltage down to 3 volts, it doesn’t get hot, but I dont think it will charge. After about 10 minutes it only twiches a little.
And of course, if I set the voltage to 6 volts it just gets hot faster.
Any ideas would be greatly appreciated.

[icebreaka]

i just wanna say congrats on the wedding!!! :smiley16: hehe..

[leonli17]

mmm…Does the batteries get hot when the PCB get hot? And when u got 4.8V total voltage. Then u need something higher voltage to charge it.
I don’t know how the PCB gets hot, we just have to wait uA to answer this one.

[HACHI-RYOKU]

Thanx icebreaka!

No, the batts don’t get hot. Just the pcb. Right around where the chip is. It may actually be the chip. Yeah, I’m kinda thinkin I need around 5~5.5 volts to charge it. But I’m not certain.

Hey leonli, I looked at your Gallery. Nice pics. Where did you get that Skyline that you’re comparing to the bit Skyline? What is it? How does it drive?

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