so what's the deal with SBCG tronics?

ph2t · Post by **ph2t** » Fri Jul 29, 2005 9:22 am

so fellas, I gots a few sbcg's now and being outta the 1/64 hizzay for a while I just had a few questions

* Did we ever get a good mosfet mod for 'em?

* Did anyone upgrade the steering transistors with any (noticable) effect?

* Anyone do a daul cell on 'em? I guess it would be tricky given the streamlined chassis layout.

cool yo.

ph2t.

betty.k · Post by **betty.k** » Sat Jul 30, 2005 3:03 am

you noob!

have a look back in the ausmicro forums. i remember microamps tried with little success. i think they're regulated too so more cells does nothing.

crazydave · Post by **crazydave** » Thu Aug 11, 2005 5:51 pm

Yeah, I figured if microamps can't figure it out, then I'm screwed, so screw it. My SBCGs are nice display pieces though.

ph2t · Post by **ph2t** » Thu Aug 11, 2005 6:06 pm

Well, you never know.

All mosfet mods for 1/64 shit have been based on the all n-chan mosfet h-bridge circuit. This circuit has a weakness in the fact that it requires a (sorta high) drive voltage of at least 3v to make it work. ZZ's, bits, clones, zzmt's all provide this needed drive voltage and hence they work, and work well.

Recently in testing and making the bug turbo for epochs I found that the drive voltage is shithouse and therefore an nchan and pchan mosfet design was needed. This way, the bug turbo works.

The biff turbo though which is an all nchan mosfet design went like a sack of shit and didn't work on an epoch at all.

So maybe, my point is that what we need for sbcg's is the nchan/pchan h-bridge design. This may just work.

Time will tell, god knows when I'd get a chance to work this out.

ph2t.

crazydave · Post by **crazydave** » Thu Aug 11, 2005 6:42 pm

If you'r saying a direct swap of the Ns for Ns and Ps for Ps might work with the SBCG, then I'm game. I'll go try it. WTH, I was bored and looking trouble anyways.

ph2t · Post by **ph2t** » Thu Aug 11, 2005 7:00 pm

possibly, I'm talking about creating an external circuit and running it off to key signal points from the sbcg pcb. But I dunno. You'd have to see how it goes!

ph2t.

crazydave · Post by **crazydave** » Thu Aug 11, 2005 7:44 pm

Ahhh, I get ya. So basically you're gonna see if you can adapt your bug turbo?

So should I bother trying what I was gonna do? (Even though I probably will anyways before you reply, since I already got the iron all warmed up, but just in case.

)

ph2t · Post by **ph2t** » Thu Aug 11, 2005 8:19 pm

prolly best not to mate. the reason being that the sbcg is a singel cell and it's been stated on the german site that the direct n an p mosfet swap only works on daul cells where the voltage is high enough to turn on the p chans.

Actually, now that I've said that, it prolly kills my idea as well for the bug, damn!

But we'll see. I guess we can turn this into a testing thread. (like the sucessfull zzmt one).

do you know what transistors drive what on the sbcg pcb? I'm yet to go down that road.

ph2t.

crazydave · Post by **crazydave** » Thu Aug 11, 2005 8:48 pm

Actually the info from the German site is not totally accurate, from my experience. Ever since you introduced me to those 6401s, I've been using them on all my FET mods. So much quicker and easier to do a direct swap. It works totally fine on my bit and ZZ PCBs. I think maybe all Ns has slight advantage, so I sometimes stack the P channels and that seems to even them out.

I gonna go ahead and try. Worse that could happen is I have to swap 'em back to stock.

ph2t · Post by **ph2t** » Thu Aug 11, 2005 8:52 pm

that's interesting, hmmmmmmmmm.....

might go and do some modding........

crazydave · Post by **crazydave** » Thu Aug 11, 2005 11:40 pm

Well got some interesting results, we'll see if this means anything to you.

First off, a little off track, I had zero glitching tonight making the SBCG a thoroughly enjoyable car. Haven't tried it in my new apartment, oddly 49mhz doesn't work so hot here. Apparently 40mhz does.

Anyways, I swapped the forward P-channel first. The layout is the same as an OG bit. I definately noticed a difference in the pitch of the motor in going from forward to reverse. I swapped out the other P-channel and it seemed faster in both directions off the ground. I put the forward N-channel in, and it died. Tried another FET, just in case, still nada. So I put the original tranny back in, and ran it on the track. Maybe a slight improvement in off the line punch. Hard to say because the SBCG had really good punch to begin with.

ph2t · Post by **ph2t** » Thu Aug 11, 2005 11:55 pm

well that is interesting......

can you take a pic of what you changed?

crazydave · Post by **crazydave** » Fri Aug 12, 2005 12:01 am

Yeah, it'll have to be tomorrow afternoon, though. I'm already up later than I should be, 'cause I was playin'.

ph2t · Post by **ph2t** » Fri Aug 12, 2005 12:12 am

no worries man, I'm just being slack and standing on your shoulders....

betty.k · Post by **betty.k** » Fri Aug 12, 2005 1:32 am

boy, whatta loada gobbldegook!

going from memory (b style) i recall microamps saying that the sbcg is already fetted. he was able to fetmod it, but it made little difference. or words to that effect. maybe he was ordering a milkshake