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jonnywachter
2009.04.20, 03:17 PM
I couldnt find an electronics thread, so i decided to post this in the 02 thread because it has to do with an 02.

Well, I was reading the Mini-Z definitive guide http://mini-z-guide.com/index.htm and it got me thinking, the author stated that the 2 wire POT is more sensitive than a 3 wire POT. The reason im bringing this up is because I started out with the am board but couldn't even keep up because I was fighting my car so much, from wondering servo. My idea, is if there would be a way to tighten up all the steering components, I would be able to eliminate the wondering and have a more precise servo than you would achieve with ASF.

Im not trying to find a cheap way out of not buying 2.4, because I already have it. I am just wondering if anyone has tried this or is is a complete waste of time?

herman
2009.04.20, 11:46 PM
from the site you mentioned...

The disadvantage with the 2 wire pot configuration, is that it is very sensitive to change in resistance. Fine track dust that gets into the pot adds resistance between the pot arm and the resistance element. It is intersting to note that the upgraded AD band board for mini-z use a 3 wire pot.

The solution to the pot issue is to keep it clean. Use electrical cleaner to clean the pot. DeoxIT works well to clean it followed by DeoxIT Gold for contact protector. To make cleaning last longer, seal up the openings in the pot with some sealant. With the vibration in the car, the fine dust that get into the chassis will get into any small opening.

the 2 wire pot is very sensitive to change in resistance... and dust in the pot doesn't help (it makes it worse)... the ad band and the 2.4ghz asf use a 3 wire pot configuration, which isn't as affected (or as sensitive to changes in resistance) as much as the 2 wire pot configuration...

although i haven't tried the ad band, i've got a 2.4ghz asf chassis... and the steering, in my opinion, couldn't be any better (been in the hobby since the mr01 chassis rolled out, in terms of steering, some were ok, some were so-so, others were just cr@p... then came the mr02, with the servo saver, it was such a delight - no more broken servo gears, and steering was definitely better; wasn't able to experience the ad band boards, but if they have a 3 wire pot, i'm thinking that steering, and steering response could be quite comparable to the 2.4ghz asf board... and finally the 2.4ghz asf board... for me it's the bomb thus far, almost everything that you would like in a board... better fets, better steering... oh and no more darn crystals to deal with ah but i digress)...

another tip: check your servo saver... this may cause your steering to wander... it may need replacement... hope this helps...
let us know what happens...

imxlr8ed
2009.04.20, 11:55 PM
I usually try to add a tiny dab of hotglue to the top of the pot in my cars, and then move it towards the forward servo assembly bulkhead to secure it. (sorry... hotglue addict) It takes a good portion of the "walk" away when going down straights. Make sure your radio is fully charged, make sure you're on a fairly clean frequency, always run the right antenna length (stock length always seems to be the best), and make sure all your connections are tight and clean on the chassis.

But... like I just said on a previous thread, 2.4 is the way to go. But for just starting out... an AM ESC with a single layer of 4562 fets is just as powerful as a 2.4 board, but you'll never get rid of the tiny glitches entirely.

jonnywachter
2009.04.21, 12:00 AM
Thanks for the reply, the only reason i considered it was because this past weekend at the rcx i was running 2.4 and i had to rebind my car a couple times. including once rite when i went to turn my car on for the main then i did 4 laps and it came unbound at the end of the straight. Crystals never come unbound from each other, but as mentioned they do glitch sometimes.

cowboysir
2009.04.21, 12:09 AM
"unbinding" as you call it comes from low voltage in your controller...think about charging your controller rechargables every time you head to a race.

I'm a big fan of the hot glue method as well. It helps sort a few of the twitchs as i like to call them.:D

jonnywachter
2009.04.21, 12:18 AM
my radio is always charging in the pits, the voltage is never low. I know what im doing, and the system just comes unbound randomly. Brian had the same problems.

yasuji
2009.04.21, 12:31 AM
my radio is always charging in the pits, the voltage is never low. I know what im doing, and the system just comes unbound randomly. Brian had the same problems.

me too quite a few times....i re bound my car b4 each race because in practice i had to re bind 3 or 4 times.....in just a few hours
it was the same @ the worlds......jus too many 2.4 in the house i guess.....
however id rather deal with that than glitching or shutting down like my previous am or ad band stuff.....
on the matter @ hand....i believe that the pot for am/ad/2.4 is all the same.....on the am board it only has 2 wired coming out to the pot....there for the third lead on the pot is jumped
on ad/2.4 there are 3 wires......
my ad/2.4 is far better than any am car i have ever driven:p

Eman
2009.04.23, 01:06 AM
I went to the DeoxIT website and they have alot of cleaners. Which do you use or recommend? How do you clean the pot? Do you just remove the clear plastic and spray it in there, move it around a bit then spray it again? Is there any household cleaners I could us instead? Would I be able to use the same DeoxIT for the pot as well as a motor? Please advise.

herman
2009.04.23, 02:29 AM
"unbinding" ???

that's odd... it's a first i've heard... well considering that i'm the only one i know of who actually has a 2.4ghz over here...

what were the conditions of, er the ''unbinding''? was it at a big track? and what controller are you using?

i think you can control the power output through the ics thingamajiggy you connect to your car from the computer... don't know if it will work as far as range is concerned

yasuji
2009.04.23, 02:46 AM
"unbinding" ???

that's odd... it's a first i've heard... well considering that i'm the only one i know of who actually has a 2.4ghz over here...

what were the conditions of, er the ''unbinding''? was it at a big track? and what controller are you using?

i think you can control the power output through the ics thingamajiggy you connect to your car from the computer... don't know if it will work as far as range is concerned

this was @ rcx.....pn regional track...
i have found that it is common where there are alot of ko mini-z modules
normaly when you turn on your radio the red light on the module comes on within a few seconds.....(many open frequency's)
when there are more frequencys in use...you turn the radio on and ive had it take 30+ seconds for the light on the module to come on....
most people dont notice thi so they turn the radio on and then the car....but it has no signal and doesn't find a clean frequency
it is funny tho cause when it happens to me i will rebind ...and my car will work much better...faster and more responsive;)

mleemor60
2009.04.23, 07:24 AM
After you have to rebind, is it necessary to reconnect the board with the ICS hookup to restore your settings or are they maintained on the board?

yasuji
2009.04.23, 12:27 PM
After you have to rebind, is it necessary to reconnect the board with the ICS hookup to restore your settings or are they maintained on the board?

the settings stay in tact....i think.....i better check:o

JuniorWKR
2009.04.23, 01:15 PM
i have never had a problem with the unbinding... is it just that the racers arent patient and dont wait for the module to select a channel before turning there cars on?

yasuji
2009.04.23, 01:27 PM
i have never had a problem with the unbinding... is it just that the racers arent patient and dont wait for the module to select a channel before turning there cars on?

thats what im thinking

JuniorWKR
2009.04.23, 01:31 PM
thats what im thinking

that stinks because i just took the switches of my mod cars... now i will have to wait to put the batteries in, body on and taped at the drivers stand...