Mosfets?

[baleisen]

Your discription of xistors isn't bad. Regular xistors vary their resistance in response to the voltage on their base. Like a water valve. They are there to control a larger current. Not cause it.
FETs are pretty much on/off. They have very little controlling ability. Like the 1st zip zaps, they are on or off.
BAE

[slider69]

I cant see if it has them in ur picture, in the savannah my friend has, they would be under the red and black wires in ur picture. I'lll post a pic when i find a digital camera around this place....

[crazydave]

Hey slider69, guess what? You killed my car you owe me 25 bucks!











Just kidding....YOU are da man!!! Found those stacked transistors, swapped them out for some FETs, and my car not only still worked, but has noticebly increased performance. Not as mind numbing as a fully FETed bit, but a SOLID increase in performance.

You hear that everybody....I'm sitting on the worlds fastest SE at the moment!

Thanks man, I think you made a great discovery.

Here's the ones to swap out. (highlighted in the picture)


...and I'm more than positive the one next to it will boost reverse. That will be good to help conseverve battery life.

[vtheo]

yah!!!!!!!!!!!!!!!!!!!!!!! cool beans, have you tried with the motors that wouldnt work with it before? it seems like the alloys give a good prefomance boost too, but in handling... lets see a fetted, alloyed (hehe) 4.2 SE!

[crazydave]

Well I still have the ZZ 3.4 in it, but I'm running the green 9.86:1 gears with it. I'll tell you this much, when the battery died, and it wouldn't move in reverse, it still had power to move its self foward.

I did this kinda late last night, so I haven't had time to shake it down, but based off that alone, I'd say that it should pull a 4.2 easily. We'll see.

[slider69]

Great....now to get my friends.....Did you use NPN or PNP mosfets? IM guessing NPN...but i dunno... that's AWESOME, crazydave! u only replaced the stacked ones....there are others and ill prolly try them later....

[TypeZer0]

wut's the partnumber if the FET's u used? can u show a more detailed pic? thnx

[bdebde]

If it works better with 2 stacked fets, then stack up 3 or 4. That should increase power to the motor. Stack the reverse one for more juice there too.

[Bad Company]

Man, it's times like this when I wish I was more of a techno-electronics minded person. You guys are whiz's when it comes to the performance mods on these things. I guess I'm gonna have to get my feet wet and try this out. I'll just put $25 to the side for when I burn the PCB up and have to replace it.

[micro_Amps]

Good stuff guys,
Crazydave looks like you are on the right track here, the ZZ SE may have a pulsed single transistor that varies the current to the motor.
I am itchin to get my hands on one of these to see what the hell is on that pcb, should be only a few days away now.


uA

[slider69]

Im gonna try this on my friend's with a few changes....I want to replace all the ones (except 3e's) with mosfets and see what that does.....What do u think microAmps...

[micro_Amps]

Well, be careful just changing them without first knowing exactly what the circuits are for. If you change a transistor with an incorrect polarity FET it may just not work, or worse, may damage something. Also there are transistors there that are not used as switches but amps in the RF circuit, be careful with those, you cnat change those unless you really know what you are doing.
In any case, post your results here, and goodluck.
I am still waiting for mine to arrive, should be interesting when they get here.
uA

[slider69]

Those are the 3E's i believe in the receiver amp circuit.....The others appear to be wired in an h-bridge..i have to wait a while and double check everything before i go. but ill let you know how it works...btw...how r the airplanes going?

[micro_Amps]

This is a bit off topic, but the planes are going well. I have one that already flies very well, and one that will be test flown on Monday. Both are indoor flyers (basketball stadium) and both are BCG r/c controlled (fet modded) with KP-00 motors, which are about double the size of BCG motors. The planes are tiny, about 30cm wingspan, of foam and balsa construction with Li-Poly cells powering the motor and r/c. Amazing to watch.
I will be putting pics and info on my website, I just havent had the time recently. Check every now and then, I'll get them on soon.
uA

[malform]

I think we would all like to see a pic of the moded pcb crazydave.... And if Im not mistaken, this didn't effect at all your proportional throttle?