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Felix2010
2009.09.11, 05:12 PM
Hello everyone,

I have an MA010 I modified to AD-Band. It always twitched and glitched and had crappy radio-range, and I just thought it was due to radio interference in my home. But now I am thinking there might be more to it than that.

I have another AD-Band car but this one is an MR02. I just finished rebuilding it with a new chassis, so I gave it a spin. It runs Leaps-And-Bounds-Better than my AD-MA010. I even did a head-to-head comparison using the same crystals, batteries, everything. The AD-MR02 has full range on my track; My AD-MA010 falls out-of-range after less than 10ft and goes 100% out of control, until I approach the car within range again and the car receives my radio's signal (I use a Helios). So I'm thinking it's not just a glitch issue but a also a range issue.

I have tried five different antennas on the AD-MA010: The stock antenna; an Atomic metal antenna (The old style one); an Atomic hobby-style antenna (The one with a hobby-grade signal wire inside of a colored Atomic antenna tube), a piece of CAT-5 cable approx. 30cm (solid kind, not stranded CAT-5), directly-soldered to the PCB; and finally a long 45cm piece of hobby-grade Rx cable, also direct-soldered to the PCB and propped-up using heat-shrink and a stock antenna. Nothing improved signal reception.

I am wondering if there is maybe a capacitor or resistor or some component on the main board that is blown-out, which is causing the short-range? I remember radio reception range-issues would happen with old Xmods sometimes and a new resistor or something could be replaced which helped resolve the signal & radio/range issues. Anybody got any ideas? I have put some $$$ intot his board by having a 2x3 SP8M4 Fet stack put on it by a pro-electronics guy I know, and also had the I.C.S. plug modified for the MA010 chassis, as well as other AWD-specific modifications. I'd like to keep driving this car a while longer before retiring it.:D

Hopefully somebody can help:) Thank you in advance!

mleemor60
2009.09.11, 06:45 PM
Does the board in the 02 have the same fet upgrade as the AWD? Does any part of the antennae come in contact with anything on the chassis that is carbon fiber? Is the motor in the 02 the same unit as the AWD? What is the condition of the brushes in the AWD? Armature dirty? Any arcing from the motor when power applied? Any questionable connections in the AWD car? Maybe at the board to chassis connection? All are interference factors for any AM or FM based unit. All are important.

Felix2010
2009.09.11, 10:17 PM
Hello mleemor60, thank you for the response.
To answer the questions in order:):
1.)No - MR02 has stock 3010's (4pcs), AWD has SP8M4's (6pcs). The AWD Fet job is pristine and from my experience should not cause the signal loss I'm having;
2.)No - No carbon-fiber-touching going on:);
3.)Yes, I've tried the exact same motor in both cars;
4.)The motor is a Speedy05, brushes are fresh & broken-in;
5.)Armature is clean;
6.)No arcing;
7.)No questionable connections in the AWD car, including antenna;
8.)PCB is hard-wired to battery terminals, 18ga hi-strand-count wire:).

The funny thing is this AD-AWD has worse (much worse) reception than my Old AM-AWD PCB with a 2x3 PN AN0113 Fet job 2x3 (6pcs):confused:. I am considering removing the AD-PCB and swapping-in my old AM-AWD PCB.:eek:
Since exhausting just about every simple reason I can think of for the discrepancy between the AD-MR02 and AD-AWD's performance is why I'm leaning towards the problem being something wrong with the AD-board itself.:(:(

mleemor60
2009.09.12, 07:35 AM
Since the only variant between the two set ups is the fet job then process of elimination should take you there first. How was the board performance prior to fetting? Sometimes the additional current flow capabilities can give the car what I call Red Bull disease. Jitters. The range issue mentioned in the original post could be caused by a less than ideal antenae lead connection to the board itself and is commonly overlooked while trouble shooting. Make sure there are no stray strands of wire getting friendly with something they shouldn't.

Felix2010
2009.09.14, 02:07 AM
If I remember, there was always less reception with the AD-MA010, since the AD-PCB was converted to the MA010 platform. Even though the Fets are different, the Fets don't look to be the problem. And I just re-did the antenna and it is clean and tidy... No unfriendly (component) touching going on:D

I am thinking it might be a crystal problem. Not a frequency problem though - I have a #3,#6,and #19 AD crystal set. It's a connection problem -> That the crystal's pins don't sit as securely inside the PCB crystal socket as a crystal does on an AM board. The AD crystal is secure to a point, but not very tight; The crystal has some play that I don't like.

I first found this crystal-play to be a problem for the Lay-Flat crystal adapters made by PN and Atomic. The crystal-adapter pins wouldn't be very secure inside the crystal socket, and I did some experimenting way back when and the AD-MA010 had better reception when the crystal was installed directly into the AD-PCB rather than when the crystal was used with a Lay-down adapter, neither the PN or ATM adapter worked well with the AD-PCB. On my AM MA010 the crystal lay-down adapters for both companies worked much better> Much more secure.:)

Right now my AD-PCB has the crystal socket re-soldered at a 45-degree angle, the old DIY lay-down crystal mod.:) I am wondering if I should try soldering thick-gauge wire to a crystal's two pins, and then taking the ends of the wires and stuffing them into the PCB's crystal socket for a tight connection. I have never tried or heard of anyone trying to solder wires directly to a crystal, and I don't know if it's a good idea since I'd like to be able to remove the solder & wire and use the crystal in my other AD-MR02 in the normal plug-in way.
Anybody got any ideas/tips/tricks on how to get a tight connection between the crystal and the PCB? :D

TheRinger
2012.05.01, 12:51 PM
I got a question, I have a AD band board I got a few years ago and when I power it up the throttle works fine but as soon as I turn the wheel it locks to whatever side I turn to and doesn't return to center when I let off the steering wheel. I got it used so no warranty implied. I installed a new steering pot on it and resoldered the motor and nothing works. Please help.

Felix2010
2012.09.05, 01:04 AM
I got a question, I have a AD band board I got a few years ago and when I power it up the throttle works fine but as soon as I turn the wheel it locks to whatever side I turn to and doesn't return to center when I let off the steering wheel. I got it used so no warranty implied. I installed a new steering pot on it and resoldered the motor and nothing works. Please help.

Hello,

I know it has been a few months since this Q was posted, but I am still interested in AD cars and have a couple myself.:) The steering problem you've described sounds to me like possibly the pot's wires are not correctly soldered onto the pot on the correct pins (If you bought the unit *used* this is possible I would think(; Or maybe the pot is installed upside-down in the servo assembly? If the Pot is installed up-side down (with the 3-prongs pointing upward-away from the POT, maybe this would cause improper POT finction..

Just a couple thoughts! Hope this helps!:)

herman
2012.09.05, 04:13 AM
hmm... the only thing i can come up with is the antenna wire connection...
but since you mentioned that the wire is "directly-soldered to the PCB" it might be ruled out...

although i never had any experience with ad band cars, i did however experience the same thing that you were describing in one of my am cars.... "a loooong time ago"

after checking the antenna to where it was connected to the board, i found out that it was not a good solder....

after reading some stuff, i think it was an article from draconious - that pointed out that there are other spots on the board that could provide a better reception... i tried it out and relocated the wire and viola... the reception issue was gone...

herman
2012.09.05, 04:27 AM
found the link... hey doc let's go back to the future... click below...

antenna alteration (improvement) by draconious (http://mini-zracer.com/forums/showthread.php?t=5112&highlight=antenna)

dunno if the ad board looks anything like the am board below...

draconious mentions "In some cases the antena resolder wont even work... and with the new PCBs out this photo is very obsolete... the components are layed out different.
Whatever you do, dont use more than one color! or it will short out... yellow is original antenna location. Cyan/blue worked best for me I used the hole...."

http://mini-zracer.com/forums/attachment.php?attachmentid=21754&d=1166300309

herman
2012.09.05, 04:31 AM
another article by draconious regarding antennas (http://mini-zracer.com/forums/showthread.php?t=20538&highlight=antenna)

herman
2012.09.25, 10:06 PM
hmm... any update?

TheRinger
2012.11.03, 09:23 AM
Hello,

I know it has been a few months since this Q was posted, but I am still interested in AD cars and have a couple myself.:) The steering problem you've described sounds to me like possibly the pot's wires are not correctly soldered onto the pot on the correct pins (If you bought the unit *used* this is possible I would think(; Or maybe the pot is installed upside-down in the servo assembly? If the Pot is installed up-side down (with the 3-prongs pointing upward-away from the POT, maybe this would cause improper POT finction..

Just a couple thoughts! Hope this helps!:)
LOL I forgot about this thread:o. I'll have to give it another look. The person I bought it from originally had it in a AWD and took the board out and sold it to me along with the module. I was wanting to use it in a MR015 since I already have an AD band MR02 and enough spare parts and a skeleton MR015 chassis laying around.:D I just resoldered the wires on the way they came off, never thought if they were soldered on the right tabs to begin with. I'll give it a look.

reaper
2012.11.03, 12:27 PM
LOL I forgot about this thread:o. I'll have to give it another look. The person I bought it from originally had it in a AWD and took the board out and sold it to me along with the module. I was wanting to use it in a MR015 since I already have an AD band MR02 and enough spare parts and a skeleton MR015 chassis laying around.:D I just resoldered the wires on the way they came off, never thought if they were soldered on the right tabs to begin with. I'll give it a look.

Its the two outer wires that are the wrong way round mate