Weird Scientist in the making.

pimpsmurf · Post by **pimpsmurf** » Mon Jul 11, 2005 8:10 pm

Tired of bowing to the sometimes excessive knowledge of ph2t and others, I bought the book "Teach yourself Electricity and Electronics 3rd Edition" by Stan Gibilisco (Published by TAB Electronics). I've already learned what p-channel and n-channel MOSFETs do, and why you need 4 chips to do forward and reverse. Now all I have to do is use a voltage meter on my OGZZ and I'll know which ones are P and which are N (could probably do a lookup on the part numbers, but... I'm learning). Then I'll replace those and start the process of ripping out resistors until it does what I tell it too. Maybe I should read all 700 pages before I go jumpering this and that. Or maybe it will be fun. Fun usually wins vs. reason.

Anyway, I'm expecting my first Bit (Microsizer Auto Modellica) set this week which I've desided to keep together. I already recieved my R-Type II motor (which seems to suck butt in an unmodded OGZZ/ZZSE. Probably needs 2.4-3.6v to really show it's color. Anyway, Maybe I'll actually have something more than advice to contribute to this site in the future.

Well, off to read,
-JNY

payaso · Post by **payaso** » Tue Jul 12, 2005 3:14 am

Awesome dude.... Knowledge is power.

silla

civicsr2cool · Post by **civicsr2cool** » Tue Jul 12, 2005 8:24 am

sounds like a good way to learn......teach urself so no teachers have to get in the middle

pimpsmurf · Post by **pimpsmurf** » Wed Jul 13, 2005 7:31 pm

Who didn't see this coming? lol

So, If I have a 3.6V car, and lets say the motor is hooked up to the battery with two resistors (equal value), one on each side of the motor...

Is the motor really only getting 1.2V or is it considered to have 1.2EMF for the purposes of Ohm's Law? I promise I'm going to go buy a big box of resistors and such... searching now!

Anyone know somewhere to get a good (preferably analog) multimeter with small leads and around 20A-DC range cheap? I really don't want to spend $100. That is a *lot* of ZipZaps...

Thanks,
-JNY

mod_o_matic · Post by **mod_o_matic** » Wed Jul 13, 2005 9:10 pm

pimpsmurf wrote:Who didn't see this coming? lol

So, If I have a 3.6V car, and lets say the motor is hooked up to the battery with two resistors (equal value), one on each side of the motor...

Is the motor really only getting 1.2V or is it considered to have 1.2EMF for the purposes of Ohm's Law? I promise I'm going to go buy a big box of resistors and such... searching now!

Anyone know somewhere to get a good (preferably analog) multimeter with small leads and around 20A-DC range cheap? I really don't want to spend $100. That is a *lot* of ZipZaps...

Thanks,
-JNY

Could try rat shit (radio shack

) but you will most likly get raped in teh ass. Look for an electornics store around you though. I got mine at (heh) Canadian tire and it works great

stampede_dude · Post by **stampede_dude** » Thu Jul 14, 2005 10:08 am

www.allelectronics.com is a good site to mark. they have wholesale stuff for dirt cheap.

pimpsmurf · Post by **pimpsmurf** » Fri Jul 15, 2005 1:14 pm

(Best Quagmire voice) Alright!

I've been learning entirely too much from this book. I made it to the chapter on FETs and learned what the difference between p channel and n channel FETs are. (Was a big DUH moment for me.)

Anyway, I'm wondering if there is a way to use a large inductor or something to taper the voltage (or current) to the motor on a ZZMT. The idea being to reduce torque from a stop to pop a wheelie without rolling all the way back. Rollbars anger me, and can't seem to get this silly rewound motor to work yet. Give me time though!

Will I need some sort of flash-programmed IC to pull this off (like the DC-Mod ZZSE Chip only reprogrammed?) Perhaps a timer/switch/resistor would be more elegent (with only 2 stages however). Basically .5 or 1 seconds running through a resistor to the motor and then the switch would pop over to the direct feed. Might make it pop two wheelies without rolling...

I'm trying to keep all my stupid electronics questions contained to a single thread. That way my ignorance won't spread any further than needed.

BTW, I'll be working on a carbon fiber driftshaft here shortly. My friend is bringing the calipers over to get some measurements so we can order some CF Rods. Kind of setback for the too much torque problem!

Hopefully this motor will be finished today!

-JNY

Post by **CaboWabo** » Fri Jul 15, 2005 4:04 pm

Wow dude.
Really looks like you're taking all this stuff head on, can't wait to see what kind of "Weird Science" nut you grow into.

ph2t · Post by **ph2t** » Sat Jul 16, 2005 10:12 am

pimp, don't waste your time mate fucking around with that non-propo shit. just chuck an iwaver PCB into the bastard. you'll be a lot happier, trust me. LBRC and betty.k each have down conversions to a great deal of success.

ph2t.

pimpsmurf · Post by **pimpsmurf** » Sat Jul 16, 2005 12:27 pm

Alright. But now I have to take this big nasty stack of FETs off of there! Now I have to figure out what kind of i-waver board to put in. (I-Waver 02?) I'm guessing I'll need an i-waver remote too. I'll figure it out.

Now that I have that out of the way, can someone tell me how I can use a 150mAh lipo charger to charge 145mAh cells? I believe lipo chargers put out 3.6V, but I'll check that. What I wonder is, do I just throw a single resistor array in between charger and cell one one side or the other? If the charger is indeed putting 3.6V out, I believe 720 Ohms of resistance will provide the 5mA drop to the cell I need. What I wonder is will the battery charger still work? The problem I think I may encounter would be that when the charger drops voltage to top off the battery, the amount of current the resistor is resisting will drop.

Am I over-thinking this? Should I just try to charge the 145 at 150? 1.0C Charging rate is awful close to 1.03448

-JNY

civicsr2cool · Post by **civicsr2cool** » Sat Jul 16, 2005 12:36 pm

pimpsmurf wrote: Should I just try to charge the 145 at 150? 1.0C Charging rate is awful close to 1.03448

-JNY

its prolly close enough to burning ur house down too

pimpsmurf · Post by **pimpsmurf** » Sat Jul 16, 2005 12:44 pm

I know! hehe. I don't want to get a separate charger for 145 if I can avoid it. There must be a way without a voltage switch PCB with various resistor banks for each voltage level. (If that is even needed.)

*EDIT* I am totally lost now. I wouldn't imagine that 840ohms would resist less current at 1V than at 4.2V while 200ohms of resistance would resist less current at 4.2V than at 1V. I'm thinking a configurable charger is the way to go. I have 6 Kokam 145s on the way, so I might try to charge one with the 150mA charger and see if it can handle it or it it starts a nice pretty fire in my back yard. If anyone has anything to contribute, I would appreciate it. I'm sorry for not knowing what the hell I'm talking about.

-JNY

civicsr2cool · Post by **civicsr2cool** » Sat Jul 16, 2005 1:58 pm

id definately take lbs standpoint on this before charging

no need in lighting ur nice charger up on some little batts

ph2t · Post by **ph2t** » Sat Jul 16, 2005 8:04 pm

pimpsmurf wrote:Alright. But now I have to take this big nasty stack of FETs off of there! Now I have to figure out what kind of i-waver board to put in. (I-Waver 02?) I'm guessing I'll need an i-waver remote too. I'll figure it out.

Now that I have that out of the way, can someone tell me how I can use a 150mAh lipo charger to charge 145mAh cells? I believe lipo chargers put out 3.6V, but I'll check that. What I wonder is, do I just throw a single resistor array in between charger and cell one one side or the other? If the charger is indeed putting 3.6V out, I believe 720 Ohms of resistance will provide the 5mA drop to the cell I need. What I wonder is will the battery charger still work? The problem I think I may encounter would be that when the charger drops voltage to top off the battery, the amount of current the resistor is resisting will drop.

Am I over-thinking this? Should I just try to charge the 145 at 150? 1.0C Charging rate is awful close to 1.03448

-JNY

As long as it's a little over, don't worry! Lipo chargers charge at a CV (constant votage) CC(constant current) design. AS the lipo reaches it's peak , the lipo charger will adjust it's current charge to a lower value.

Don't fuck with the circuit mate. It's best left as it is. trust me.

ph2t.

pimpsmurf · Post by **pimpsmurf** » Sun Jul 17, 2005 1:54 am

My bad. I was looking at batteryuniversity's lithium ion charging graph and for some reason had it in my head that lipos use the same charge curve. Well, if they charge at the same voltage the entire time, it wouldn't be that hard to pop some resistors inline to the battery to make it right for a 145. I was thinking a small circuit board with a little resistor array to make a 5ma drop in current.

Anyway. I'll follow your advice, and hope I don't have to use this bucket of sand!

-JNY