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rperkins

Member Since: January 12, 2012

Country: United States

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Linux , rc helicopters, learning microcontrollers, music. http://9xrprogrammer.com http://www.randyperkins.com

  • Product ROB-11162 | about a year ago

    yea. I had posted my battery troubles above. Basically if you leave it on it will run the battery all the way down and it wont charge. I had to remove the battery and hook it up to a power supply to get the voltage on it high enough for the usb charger to work. I dont remember the voltage I used. If the battery is a 1S then 3.5 volts from a power supply for 3 minutes is probably enough to get the usb charger to be able to properly charge the battery. It’s not good to run the battery all the way down so now I am sure to turn the unit off when not in use. Sparkfun gave great customer service over this issue as they always have done for me. I just keep coming back :)

  • Product ROB-11162 | about a year ago

    UPDATE - the Rechargeable Li-Poly Battery is bad. I replaced the battery with a 1S li-po battery out of a syma s107 and the unit runs and it appears to be charging. After a partial rundown and recharge I can see changes on the battery meter led’s. I also tried to charge the original battery after removing it from the car through my li-po charger. It did not work. the battery is completely dead. I connected to the charger before the small safety board in the battery, so I am pretty confident it is the cell itself. I have contacted support and am sure they will rectify the situation. A replacement battery will fix me up.

    UPDATE2- So maybe it wasnt exactly the battery. When the temporary battery I installed ran all the way down the car acted the same way. It was completely dead and wouldnt charge. I left it off for a while then turned it on and it had some residual power. Then I hooked it up to the charger and LEFT THE UNIT TURNED ON. Then it would charge. I had noticed that the battery is soldered to the VCC/GND connections and the BAT/GND are left empty. It is the same way on these pictures.
    http://code.google.com/p/meisjohns-projects/source/browse/trunk/I_Racer/#I_Racer%2FImages I wondered if maybe the battery is soldered up to the wrong location, which is allowing the battery to be drained all the way to 0 volts. It also would explain why it only charges when turned on. I could be mistaken though. I took the original battery that I thought was bad and hooked it up to a 3.7 v dc power source for about 30 seconds. This put enough charge into it so that I could charge it with my RC LI-PO charger. Previously the charger complained that the voltage was too low to allow a charge. I was able to charge it up successfully. Not sure what to tell support when they email me. The thing doesnt charge properly and it appears that the battery could possibly have been soldered to the wrong spot on the pcb ??

    UPDATE3-reinstalled the original battery and it is working. Tried to hook it up to the BAT/GND connections but it wouldnt turn on. So my latest guess is it will charge if you leave it turned on and dont run it all the way down. Trying to run it down now :) After flying heli’s, the battery in this sure lasts a long time :) . Another note: when using the ‘tilt mode’ on my Samsung S3 android phone, after a while the phone must not recognize any activity and goes to sleep? . the car continues to run at whatever setting were active when the phone goes to sleep. ( no failsafe ?) Then have to unlock my phone and then all is well until it times out again. Guessing the app would have to be updated to keep phone from sleeping. I Dont expect an update for the app and havent seen any source for the app, to allow someone with the proper skills could patch it. Still lots of fun and potential for the $$

  • Product ROB-11162 | about a year ago

    Mine doesnt seem to charge now either. I only raced it a couple times but thought I had checked the charging . The light on the usb plug doesnt come on whether the car is plugged in or not, or whether the car is on or off. I do measure 5v coming out of the usb plug and also on the charging socket ? Gonna see if it charges overnight then contact support.

    It was fun when it worked. My daughter liked it also. Bought it to hack with but havent gotten that far yet. Another person had reported that it was way too sensitive when using the ‘phone tilt’ mode, but it worked fine after getting used to it. Lack of proportional steering is what I miss, but at the price point it sells I am not complaining. Another complaint was the location of the on-off switch, but that has not been an issue and the switch itself is pretty firm.

    Have looked at the source code and it is compiled with imagecraft compiler, which I wasnt familiar with. You can download a demo of the compliler needed. I have checked out the above linked alternate source and am going to try it, but havent gotten that far yet.

    Overall a good value with lots of tinkering ability, but mine is down currently. Sparkfun support has been good in the past and if I need them over this, am confident it will be the same.

  • Product BOB-09816 | about a year ago

    I think I am running into the same thing. The schematic shows a capacitor on the input and between the stages. So this board is ac coupled. when you press down on the load sensor the output changes relative to the change of the input. But when the input is a DC, the output stays at ~2.5v , or half the VCC.

    I’m wanting to use an op amp to increase the sensitivity of an ACS712 hall effect current sensor. The one I have is rated for 20 amps but I just want to measure a couple hundre milliamps and get a good resolution into arduino. The data sheet for the ACS712 shows an example with an op amp to increase the gain of the mV/A output. I think the AC coupled inputs of this OPAmp breakout are getting in the way.

    OF course I am just learning so could be completely mistaken :)

  • News - March Caption Contest | about 2 years ago

    just give me my flippin' treat. come on already

  • Product RTL-11022 | about 2 years ago

    Well, I’m having fun with arduino, but not so much with this inventors kit. Maybe I am just picky.

    1. The uno R3 does not fit properly in the holder. Has to do with the relocation of the reset button. I broke of one of the tabs on the holder trying to accommodate for this. Well the R3 just came out so I was giving a pass on this one.

    2. The 1/6 watt resistors leads are just too flimsy to be used over and over while setting up different circuits. Would it of cost you that much more to use ¼ watt ? Makes things so much nicer

    3. The retail case was a disappointing.. I guess I was expecting something with hinges. Just feels cheap. Maybe this is just a personal preference thing.

    4. The Dc motor is what put me over the edge. So I’m working through circuit 3, and the motor just wont spin. Checked everything out. Even supplied my own ‘optional’ capacitor since the arduino was resetting. Got out the wall wart to power arduino instead of using USB. Hooked up a relay to isolate motor. no go. Then came to website to see if anyone had issues. Wait that’s not my motor. Oh, looks like someone saved a buck and gave me the $1 motor instead of the $2 motor. well the cheaper motor says it draws 320ma as opposed to the 70ma the other motor is spec’d at. Wouldnt be surprised if it is more as it still pulls down my 350ma wall wart.

    5. Oh and would it be asking too much to have gotten a few jumper leads in the color ‘black’. just sayin.

No public wish lists :(