Custom H-Bridge (tha MOSFET mod)

Mostly dealing with electronics and pcbs and modifying them, all the things that make electrical-engineers tick and the rest of us cringe in fear.
payaso
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Post by payaso »

noxorc wrote:head ache? I think it looks like the starting project for the next StarWars character.

WireHead and PuddyButt.


-nox
Dude, you crack me up sometimes.. I think puddy butt could be the pilot of hogs butt char G...


silla :D
payaso...... :)

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noxorc
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Post by noxorc »

payaso wrote:
noxorc wrote:head ache? I think it looks like the starting project for the next StarWars character.
WireHead and PuddyButt.
-nox
Dude, you crack me up sometimes.. I think puddy butt could be the pilot of hogs butt char G...
silla :D

I'm here just to make sure your happy sometimes.


-n
jedclampit
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Post by jedclampit »

una pregunta, how's it going on the projecto Ph2t? Ready for mass production on that home cooked fet board yet?
ph2t
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Post by ph2t »

Getting there man, I'm still stuck trying to switch the FETs on without having to remove the original transistors. This is a key to the design and how I want to get it done. If I have to remove some components then it defeats the purpose of this mod which is to be able to give the lay person an easy mod to put on the oringinal RX pcb.

But I'm getting there and won't give up no matter how :-( I feel.

ph2t.
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Post by ph2t »

Oh, and welcome to the crib homie :-).

ph2t.
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Post by Z-Dogg »

Yo if i could buy one of those pre moded I would . Just becuse i dont think im that smart to make one :D:D:D:D
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Post by ph2t »

Looks like you can dance well though, lol.

ph2t.
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UPDATE

Post by ph2t »

Well last night I got a bit futher with this. I figured out how to start switching the FET's on/off by using the 2 outputs of where the motor is usually connected to the RX pcb. The only bugger is that I fired a pcb doing it, dang! :mad: Here I was, stuffing around *ehgmm* I mean "analysing" the problem and I noticed that there was some smoke coming off the pcb. "That's funny", I said, thinking that I hadn't use the soldering iron yet and a moment later I heard POP, FIZZLE, FFFFFFFFFFFFF. (The sound was like a fart with butcheeks spread, lol).

Oh well another RX pcb gone to God.

Dang!

ph2t.
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Post by CaboWabo »

lmfao :???: what's that smoke doing there? lol

ah well, sacrifices must be made to the gods on a regular basis if you want to keep good fortune lol
Dear Life Cereal, Where do you get off? Part of a balanced breakfast and delicious? Who do you think you are? By now you may have guessed I'm speaking ironically and have nothing but good things to say about what you do. Life cereal do not change a thing.
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Post by ph2t »

Anyone got any spare virgins? :tits:

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Yugo DSC Maxxer
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Post by Yugo DSC Maxxer »

I have just a chassis and a pcb....
You want it?
EDIT: It's antenna fell off... :x
Image
Fu-diddly-Uck Flanders!
ph2t
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Post by ph2t »

Yugo DSC Maxxer wrote:I have just a chassis and a pcb....
You want it?
EDIT: It's antenna fell off... :x
No thanks dude, but thanks for the offer.

ph2t.
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Post by ph2t »

Game Over!

I've officialy stopped development of this one 'cause of a few reasons:

1) The problems holding production weren't solved, bugger * tricky*. bugger *too hard*, bugger *too slack*.
2) The whole extra pcb thing is good in principle, but ultimatly takes too much room.
3) When the mosfets are put in you get a 3V output from the RX chip vs. the 0.7V output with the original BJT transistors. This voltage increase is due to the fundamental differnce between BJT's and FET's. 3V is still enough to properly turn on the FET's, I trying some different model FET's now that work well at 3V.

I still want to tweak/experiement with this mod and I will, just not in it's current from.

Keep your eyes peeled....

:-)

ph2t.
burgan
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ph2t i have a question...

Post by burgan »

going back to your original design on pg 1 of this thread.

you show a picture with the two yellow square showing where you hook up the FET's on the auxiliary pcb. are these the FWD and BACK pulse signals that come out after the 3 volt converter? ARe these the signals that turn on the FET's gates in the H-Bridge?

also could you explain why there is a need to do anything with the steering. if one keeps the two steering bjt trannies on the board wouldn't the steering still work?

thanks a lot, this mod seems like a doable one for me as there is no way i can solder on the so-23 fets.

jeff
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Re: ph2t i have a question...

Post by ph2t »

burgan wrote:going back to your original design on pg 1 of this thread.

you show a picture with the two yellow square showing where you hook up the FET's on the auxiliary pcb. are these the FWD and BACK pulse signals that come out after the 3 volt converter? ARe these the signals that turn on the FET's gates in the H-Bridge?
Yes they are the signals, but they come from the RX2/6 chip not the DCDC converter. The RX chip needs 3V to run that's what the DC convertor is for. :lol:
also could you explain why there is a need to do anything with the steering. if one keeps the two steering bjt trannies on the board wouldn't the steering still work?
There's no need to do anything with the steering at all and yes it would still work. Fet steering is better, but only barely so. Works best on full wheel mods, pulbacks...

oh and welcome to the real deal man.... :smile:

ph2t.
People are mean to you because you're a fucking idiot.
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