micro_Amps
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Glad you like them JackD and Bdebde. 😀
Thanks for the kind words.
:)uAWeapon, yes the fet mod will easily handle a tricell mod. It is seriously fast.
A tricell fet mod hits over 28km/h :shock::shock::shock:
Yeh I know, crazy, but true. Hard to control but DAMN fast. I havent tried a 4 cell fet mod yet.
Motors last ok, so long as you dont run them for long runs on a running treadmill or the like, and you let them cool down after runs. They do tend to get hot.
:)uAZ-beam the ‘a’ setting is for running non booster cars as they use a different signal code timing.
:)uA
Z-beam the ‘a’ setting is for running non booster cars as they use a different signal code timing.
:)uA
:D:D:D:D:D:D:D:D
Another satisfied BCG owner now travelling at close to the speed of sound.
Glad you like the rocket HiCH, they kick ar$e fet modded as a dual.
:)uAThere is a controller mod for this called the antibooster mod. It reverses the signal so the car stays on boost and goes off boost when you push the button. But I think I like the normally closed push button idea better.
:)uA
There is a controller mod for this called the antibooster mod. It reverses the signal so the car stays on boost and goes off boost when you push the button. But I think I like the normally closed push button idea better.
:)uA
Do they have trackdacks in Sweden?
Yeh, what the hell, blend it. 😀
:)uATalldude the pullback wheel mod is a good one, it makes the car sit lower and handles well on a grippy surface. I find the tyres a little too hard for the fast cars though. The rears need to be sticky or the car slides out all the time. For the fronts, I use medium to hards, I find softs grip to much and the car flips. (Its horses for coarses though, see ph2ts post above) Depends on the surface you are driving on.
Do the front wheel mod, it makes the car lower and has a good look to it, dont forget the little extra bits you have to add on the front axel pins.
:)uAOK Trackmaster, I’ll take the bait….
Tell us what it does and does not do.
It doesnt work on the charger without a cell in it? but it does work on the charger with a cell in it.
Is the cell in the car being charged? or is the car running on an already charged cell. That would mean a broken charging contact.
I’m sick of this already.
Fill in some gaps for me, I need more info.:)uA
hehehe, probably right.
I think it has something to do with my poor overworked computer having 10 explorer windows open at the same time. The vid runs quick when I only have the one window open.
:)uAThe NiMHs in BCGs dont fully discharge. The car stops working at about 0.7 or 0.8 volts and this stays in the cell untill you recharge it. It IS quite flat but not completely, so it lives to be charged and run again.
:)uAI’m sure the other ex-ebay sellers are in a similar situation too.
:)uACharger theory 101…..I can feel a long post coming on.
Perri, let me try and make a start on an answer for you, ph2t will probably hit you with schematics, graphs and a video at 1.00am (lol :), just kiddin’ ph), but maybe I can provide some preliminary explanation here.
Firstly, do you have a multimeter, because you are going to need one. Even just a $10 digital multimeter will do fine. Two of them would be ideal.Unfortunately you cannot simply adjust the current with a variable resistor, its not that easy, the current will be determined by the voltage supplied to the battery. More on that in a minute.
Just to clarify a few things, on an LM317t the variable resistor between the ADJ terminal (pin 1) and ground will adjust the output voltage. The resistor between Vout and ADJ is a feedback resistor (of about 200 to 400 ohms), its fixed and it makes the output more stable, you cannot change the curent by varying this resistor. These are all the lm317 needs to operate as a voltage regulator.
Build the power supply as per the instructions and then put your multimeter accross the output to test that you do indeed have a variable output voltage that you can control.
Then put your mulitmeter (or the other multimeter) in series with the positive output terminal and connect a single cell to the power supply. (positive output to positive on the cell, negative out to negative on the cell) The minimum output of a LM317 is 1.27 volts, this isnt enough to charge a cell, so you should see almost no current going to the cell. Turn the variable resistor VERY slowly to increase the voltage accross the cell and you should see the current into the cell increases rapidly. It doesnt take much to get 1 amp running into the cell. Be careful though, your 317 is only rated at 1.5 amps and will shutdown when it gets too hot.
When you see 1 amp running into the battery, check the voltage accross the power supply, you will probably find that you need as little as 1.4 or 1.5 volts accross the cell to push an amp into the cell. This can be your first setting for charging a single cell car. 1 amp for about 90 seconds makes for a reasonable amount of charge and a decent run time.
You need to adjust the voltage and check the current and write them down and this will form a list of steps, that you can go back to if you want to charge the same type of cell. eg single cell 1.5v charge for 90 secs @ 1amp, dual cell 3.0v charge for 90 secs @ 1.2 amps, etc etc.
For a full charge, charge at about 5mA for 12 hours, this will fill a standard cell overnight. Quick charge at just under 1.5amps for 1 to 2 minutes, but keep an eye on how warm the cell is getting. Heat whilst charging will prematurely kill the cell
You are right about the adjustment being touchy. Try putting a 2 ohm 5 watt resistor in series with the cell. The reason for this is a long story, but it will help moderate the current that flows into the cell as it is charging.
I hope this is of some help, well done on taking on a project like this. Charging BCGs with an LM317 power supply is not the easiest way, but it is effective. Good luck with the project, let us know how you go.
:)uAyou know what they say, there’s a thin line between genius and insanity.
We just have to work out which side we are on.
:)uAIs it just my computer, or has the wheelie vid (above) sped up in the last couple of hours/days?
:)uAHey Trackmaster, the internal connections of the BCGs go to the battery and pcb at the same time.
The charging contacts go to the battery (obviously) and also to the circuit board. So if there was no battery present and the car was on the charger, the car would work perfectly……you are correct!
If the car doesnt run on the charger then it is a contact problem.
If it runs when connected to the charger then the charging contacts and circuit board are ok.
If it runs when off the charger then the batter is ok
This last one is your problem, it must be the battery.
Try something, take the battery out and run it on the charger, it should work. Put the battery back in making doubley sure it makes contact. It has to be the battery, even change the battery if it doesnt work, but I still think your problem lies with a battery connection.
Any chance of you posting a pic?
:)uAI went to the local guitar shop and bought some fine guitar wire, it is very very very thin, but still thicker than the return spring wire. It might work tho, I’ll give it a try.
Another good idea ph2t, are you just full of them or what.:D
:)uAI’ll take some readings ph2t, and I’ll post them here. The graph shows the fet running 4 amps tho, so I would imagine the actual resistance would be slightly lower because in this graph it would include additional thermal resistance. At 4A they would be running so hot you couldnt touch them.
Still, there’s almost no difference between 0.040 ohms and 0.030 ohms accross a fet. Certainly not a measurable one anyway. I would imagine the average solder joint has a similar resistance to this.
For all practical purposes, there is a dead short accros the fet when it is turned on, differentiating between +/- 10 milliohms is surely splitting hairs.
But I will get some gate voltages, and post them.
:)uAThe only problem with those shibby is that toyeast charge like a wounded bull for postage, and the US sites charge US$20+ to get a BCG to Australia. Most of the asian sellers ship to Aus for US$12 or less.
:)uAWow, $10. They must be hurting. 🙁
:)uADoes it come THAT thin??
I’ve looked at piano wire but even the thinnest is still way thicker than the return spring.
:)uADont they have ‘Made in China’ on them tho?
:)uADont they have ‘Made in China’ on them tho?
:)uARCmod sell them but they aint cheap, and it includes the magnet. I’d love to be able to find spring wire thin enough to make my own.
Any body have any ideas ?
:)uA -
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