New Zz Pcb Mod

gpile · #1 10-08-2002, 11:01 PM

This is the mod we have all been looking for. As always use at your own risk....if your ZZ blows up....dont blame me.

there are two 68 ohm resistors that will be jumpered. Locate these resistors as follows:

1) Remove the clear cover over the PCB.
2) hold the ZZ so the motor is on the right.
3) on the PCB there is a very small resistor on the very bottom right corner just below a 3 pin MOSFET (labeled Q6). Solder a jumper across this resistor.
4) locate the same resistor just below Q5 and jumper it.

5) In summary you are jumpering the two resistors just below Q5 and Q6. Note: between Q5 and Q6 there are two resistors the one you are jumpering is the top one (the one next to Q5).

Based on test myself and others have done we know that the speed controller has a very high on resistance. I originally thought this was due to poor components etc. I now think that the speed controller is designed to not allow full current to reach the motor. Not sure why, but it seems that way.

This mod allows forward and reverse to work and boosts the current supplied to the motor by 25% from a somewhat charged battery of 1.22volts before the mod I saw 97ma after I was getting 125ma. A fully charged battery no doubt would bump the current more.

I would caution against running multiple batteries with this mod.

Cheers

latency · #2 10-08-2002, 11:05 PM

Likely much faster, eh?

Possible for you to post some pics of the process?

Thanks for the tip!

ts185r · #3 10-08-2002, 11:34 PM

Sounds like my kind of mod. I dont really like the idea of adding batteries. I got my parts car and a soldering iron. I get back to y'all in a few with my results.

Namuna · #4 10-09-2002, 12:18 AM

I'm adding this gem to the 'Look here first' sticky!

Good stuff gpile, thanks!

#5 10-09-2002, 01:24 AM

so how much improvement on the speed is there? can you tell the difference, or are you just saying the power is better according to the meter readings?

pictures of this would be awesome i definitly want to try it, but would love a pic or two to go by

Mattydiah · #6 10-09-2002, 02:03 AM

I am in the process of compiling a big giant FAQ about Zips, which will be posted sometime probably late this week or early next week. I hope to have a central repository for ZZ questions.

If you could provide a labeled pic, I would really appreciate it, as I am sure everyone else would.

Regardless, thanks a bunh for the info!!

JediYoda56 · #7 10-09-2002, 05:18 AM

How do you solder a jumper? Never solder before but I would liek to try soemtime and tips for a newbie?

Undead98 · #8 10-09-2002, 08:55 AM

I just did the mod. At first I thought you were trying to tell us to jumper the two resistors together, which didn't make sense. Then I realized that you BASICALLY wanted us to bridge each resistor together (seperately).

I was thinking of just removing the two resistors and running a layer of solder between the points, but took the ghetto way instead and just put a big amount of solder between the points (on top of the resistor). If I want to remove the solder later I can use a wick or suction.

On another note, you might want want to include the resistor numbers along with the location (ie, R19).

I also found out that the two MOSFETs on the right side of the board are paired with 2 resistors each. One set of 2 resistors and 1 MOSFET is for forward controller, the other is for reverse... very interesting.

EDIT: I assume you CAN run multiple batteries, just in parallel, just not series. Also, I think the reason the resistors were put in place was to allow for longer runtime. Since more maH is going to the motor, the runtime is shorter. So if you add a battery in parallel to the existing one, the runtime should be normal.

Thanks again for the mod tip, works great!

Namuna · #9 10-09-2002, 10:09 AM

Quote:

Originally posted by Mattydiah
I am in the process of compiling a big giant FAQ about Zips, which will be posted sometime probably late this week or early next week. I hope to have a central repository for ZZ questions.

If you could provide a labeled pic, I would really appreciate it, as I am sure everyone else would.

Regardless, thanks a bunh for the info!!

Matty,

Feel free to add upon the FAQ I already have (in my Sig)...No need to redo what's already done, but I'd love to see the FAQ become more comprehensive!

lowerdfool · #10 10-09-2002, 02:15 PM

Quote:

Originally posted by Undead98
I assume you CAN run multiple batteries, just in parallel, just not series. Also, I think the reason the resistors were put in place was to allow for longer runtime. Since more maH is going to the motor, the runtime is shorter. So if you add a battery in parallel to the existing one, the runtime should be normal.

I tryed running two batteries in parallel. you lose all reception to the radio.

Mattydiah · #11 10-09-2002, 06:52 PM

Quote:

Originally posted by Undead98
I just did the mod.

So, for those of us waiting for results before we do this, how did it work?? Big improvement? Not that big? We need details!!

Undead98 · #12 10-09-2002, 07:45 PM

Well, the mod worked out well. Here is what I found out through driving it around for awhile:

My Car: Green Gearing, Turbo (RED) motor, stock battery, stock body.
Co-Workers Car: Green Gearing, NOS (Orange) motor, stock battery, shaved body w/ drilled holes in chassis to drop weight.

I took both controllers to get a even drag start and notcies my car was now MUCH faster than his right off. I was actually beating his NOS for about 5-8', then he took over and won. I was VERY happy. This was racing a NOS vs. Turbo motor AND more weight on my end (stock body). I then had him do the above mod and raced again. This time we were dead even at the start for 5-8', then he continued to pull ahead.

This shows there is some extra speed from the start, but in the end, the motors higher RPM/top speed pulls away. I also think with this change, you can't really "beat" other people.. I consider it a 2-3 second "advantage" when racing those who don't use the this mod. Also, it seems all people with this mod will get the same quick start as others with it, ie: independant of gearing, motor, etc...

The downside... this eats my battery QUICK! Every 1-2 minutes I need to recharge. I really think the manufacturer added the resistors to increase the runtime.

Overall: A nice mod.. it has its place in certain races, but given the amount of runtime between charges I get, I'm not sure I want it all the time. This is just my PERSONAL opinion though.

If I don't see any pics from gpile tomorrow morning, I'll scan my car and post some pictures of the mod for others to follow.

gpile · #13 10-09-2002, 08:58 PM

OK here's a diagram for the mod. Sorry about taking so long....got to work and pay the bills etc. You are basically jumpering or putting a blob of solder across each resistor (not connecting them together as others have indicated).

Gomer

Mattydiah · #14 10-09-2002, 09:30 PM

Sweet, I'm all over this as soon as I get home this weekend and have access to a solder gun.

Thanks for all the hard work and info guys!!!

<IMG>This Bud's for you!

xxcysxx · #15 10-09-2002, 10:37 PM

hi guys,
are you guys talking about the microsizers. i can't seem to find these resistor you are talking about. what is a zz.