The Sub-Genius 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.
User avatar
crazydave
bitPimp
Posts: 6874
Joined: Thu Apr 17, 2003 9:05 am
Location: Koolsville

Post by crazydave »

I discovered Thunder Chargers have a different transistor arrangement, so unless your good with circuits, avoid those for mosfet mods.

My second mosfet mod went over without a hitch. This one was done to a Microsizer board. Since I knew it was going to work, I wasn't shaking, and got it straighter.

Image
...crazy man, crazy...dig it.
crazydave's Gallery
Ratfink says: "Man, it's the craziest"
ph2t
bitPimp
Posts: 1979
Joined: Tue Mar 25, 2003 6:33 am
Location: taco city

Post by ph2t »

Fellas I'm amazed. Great work and ideas. You've all done very well...
:smile:

ph2t.
User avatar
crazydave
bitPimp
Posts: 6874
Joined: Thu Apr 17, 2003 9:05 am
Location: Koolsville

Post by crazydave »

Couple more things I wanted to bring up;

I thought since the mosfets to allow more current to flow, that the battery would drain faster, but it actually runs longer. that's because the electrcity is not being burned off as heat build up from resistance.

Also, I don't notice any difference in foward speed, between the first with the partial mosfetted reverse, and the second, that I did the full foward, and reverse mosfet mod on. I'm thinking it's waste of mosfets to do reverse, and it might be better to put those toward the steering. What you guys think?
...crazy man, crazy...dig it.
crazydave's Gallery
Ratfink says: "Man, it's the craziest"
User avatar
lefftoe
bitThug
Posts: 55
Joined: Tue Jun 24, 2003 10:14 pm
Location: leff shoe

Post by lefftoe »

steering fets are useless unless you really got a heavy chassis that wont turn.........

i also doubled up the forward fet's, but that was only a slight improvment as well.........
User avatar
crazydave
bitPimp
Posts: 6874
Joined: Thu Apr 17, 2003 9:05 am
Location: Koolsville

Post by crazydave »

I was thinking the steering mosfets would be useful when using 2 or more steering springs.

My single cell cars don't like to turn with dual steering springs.
...crazy man, crazy...dig it.
crazydave's Gallery
Ratfink says: "Man, it's the craziest"
ph2t
bitPimp
Posts: 1979
Joined: Tue Mar 25, 2003 6:33 am
Location: taco city

Post by ph2t »

Mosfet steering doesn't have enough oompf to turn two springs. Mosfet steering is good for a full size wheel mod though, like on my twsited plastic contest entry. There is an improvement on steering with this mod, especially if you have suspension springs that just add a little bit more resistance to steering knukles....

ph2t.
User avatar
ezenterprises
bitGangsta'
Posts: 228
Joined: Tue May 06, 2003 10:37 pm

Post by ezenterprises »

Any diagram or info on a ZZ PCB. I was lookin at mine and theres only 4 on one side and 2 on the underside so how you know which are which and how to wire/do it??
Videos for your PSP at www.geocities.com/ebaypsp
ph2t
bitPimp
Posts: 1979
Joined: Tue Mar 25, 2003 6:33 am
Location: taco city

Post by ph2t »

Post a pic of the side that has the 4 transistors EZ, I'm sure someone could help.

ph2t.
User avatar
ezenterprises
bitGangsta'
Posts: 228
Joined: Tue May 06, 2003 10:37 pm

Post by ezenterprises »

ph2t wrote:Post a pic of the side that has the 4 transistors EZ, I'm sure someone could help.

ph2t.
I cant right now cause for some reason my comp wont recognize my damn camera.
Videos for your PSP at www.geocities.com/ebaypsp
User avatar
lefftoe
bitThug
Posts: 55
Joined: Tue Jun 24, 2003 10:14 pm
Location: leff shoe

Post by lefftoe »

the germans got the scoop on fets for zips........
microsash seems to have the inside line on fets.........
heres his writeup in german of course
http://549.rapidforum.com/topic=101684147387

i used the pictures.........works great.......

edit: if you notice on the second pic, they offset the 2 fets on the topside of the board........same as the microsizer schematic.........but there are resistors that get in the way, put a little electrical tape between the fet and resistor after you solder it in.....
User avatar
ezenterprises
bitGangsta'
Posts: 228
Joined: Tue May 06, 2003 10:37 pm

Post by ezenterprises »

lefftoe wrote:the germans got the scoop on fets for zips........
microsash seems to have the inside line on fets.........
heres his writeup in german of course
http://549.rapidforum.com/topic=101684147387

i used the pictures.........works great.......

edit: if you notice on the second pic, they offset the 2 fets on the topside of the board........same as the microsizer schematic.........but there are resistors that get in the way, put a little electrical tape between the fet and resistor after you solder it in.....
thanx for the find now maybe ill practice on my old 1st gen zz pcb's i ripped out from pcb swapping. Just need to find a supplier of the fet's now :)
Videos for your PSP at www.geocities.com/ebaypsp
User avatar
hogjowlz
bitPimp
Posts: 5014
Joined: Wed Feb 19, 2003 4:05 pm
Location: uranus

Post by hogjowlz »

User avatar
ezenterprises
bitGangsta'
Posts: 228
Joined: Tue May 06, 2003 10:37 pm

Post by ezenterprises »

hogjowlz wrote:www.mouser.com
Thanks hog but minimum order is 3000 and at .51 each that $1500!!! so ill have to pass
Videos for your PSP at www.geocities.com/ebaypsp
User avatar
hogjowlz
bitPimp
Posts: 5014
Joined: Wed Feb 19, 2003 4:05 pm
Location: uranus

Post by hogjowlz »

hey hue/superfly!! whered you guys get em?
User avatar
lefftoe
bitThug
Posts: 55
Joined: Tue Jun 24, 2003 10:14 pm
Location: leff shoe

Post by lefftoe »

http://www.digikey.com/scripts/us/dksus ... wordsearch

digikey takes small orders..........i forgot what i did, but there was a minimum order of like $25 so you dont get charged an extra $5 for handling.......i ordered 23 and they will send you 50 fets instead of the 24..........or sumthin and it came out alot less than ordering 50 fets

edit: search IRLML2502
Last edited by lefftoe on Wed Aug 06, 2003 12:14 pm, edited 2 times in total.
Post Reply