Mosfets?

[slider69]

Crap man...i take everything back...I messed with my connections a little bit...did nothing....but i changed the batteries on the controller......geez...this thing is a lot faster than a stock se....but it still lacks the torque and acceleration of my zz with msizer pcb......thats gotta be the digital to analog converter you spoke of....oh...btw.... i think the converter is under the new blob of epoxy...(the original zz only had one for the receiver chip)....

[crazydave]

I feel like no one read what I posted before.

There is an H-bridge on the output. (It's circled in red on the pic).



First I replaced the 2 stacked transistors with a FET, that improved it. Then I stacked that one, and that further improved it. Then I fully FETed all four of those, and it improved reverse, but forward only seemed slightly improved. So I stacked the one right next to the forward one that was stacked, and go reverse up to par with forward. This was testing with a Perfection 4.2, and 9.86:1 gearing. I at least got it pulling the 4.2. Acceleration is not up to par with single speed ZZ, but it is greatly improved, along with run time, making it a somewhat enjoyable car now. I think after you get yours, micro_Amps, you'll qualify that as at least a partial success.

Now, slider69 is right, there seems to be something else holding it back, and it is my theory that because these are advertised as 'digital' proportional there must be an A/D/A converter in there, (I'm guessing the big black box) and since these are just 25 dollar fully proportional RCs, I'm guessing it's a pretty crappy A/D/A converter.

Now I'm looking for evidence to support my theory, since I know very little about digital other than it pulses the current with all it's 0s and 1s clicking on and off.

[slider69]

i dunno. the big black box looks like a coil i saw in a coffee maker's timer circuit once....the thing i notice different than a regular zz is the second blob of epoxy that would cover up a small dip package.......this is usually the format for most counters, operational amplifiers, etc. , right? Or am i totally off? There is also a circuit on the back(under black paint) that has something to do with reverse....I know because i staticed a PNP fet out and it lost reverse until i replaced the fet in question...mebbe if you stack another pnp on the one that corresponded to forward.........

[bdebde]

I'm still thinkin the battery is holdin it back!

[slider69]

Dunno...definitely does on run time i figure....But something else is definitely screwy....it's a friggin 2 cell and it doesn't run like one...the weight is no excuse for a lag this great.....Gotta be the analog-digital thing...the question is how do we convert?

[bdebde]

I'm telling ya, those smaller batteries don't put out as many amps as the larger (physical size) batteries. If we could get some of the older style batteries in there, I bet it would get movin a lot better.

[micro_Amps]

Got the cars today BDEBDE, thanks very much.
Stay tuned................
uA

[bdebde]

Cool, hope to hear some good news soon!