View Full Version : Potentiometer issue
jesper1100
09-24-2010, 11:37 AM
Hello,
I have made some rudder pedals. Now I had a slide potentiometer 100k Ohm. But it was logarithm. So I buyed an linear one. But it was 10k Ohm I didn't think it was a problem. Now I connectit to my pc. And the log. one was from 0-80 on the x-axis. An my 10k linear pot was from 0-14 on the x-axis. Now you can see that the 10k pot isn't as accurate as the 100k one. Is this normal or can I add an 90k resistance or is the 10k just not as accurate as the 100k one?
No ,you cant add additional resistor to your 10k pot
I would try to calibrate your pedals via payware Fsuipc options
Regards
Joseph
jesper1100
09-24-2010, 12:42 PM
that doesn't matter the 100k is just more sensitive/accurate. What can i do?
caKus
09-24-2010, 04:31 PM
Hi,
according to me, the value 10k or 100k is not an issue. Did you check the connexions, the soldering, the smooth variation of the pot ? An inexpensive controler (voltmeter, ohmeter) can help you.
Patrick.
Agree with caKus ,about the value matter--after all the pot is just an voltage devider in this case
I would again recommed try the the payware Fsuipc calibration option , and pay attention to the slope future witch can improve the accuracy in certain regions
if that doesnt help-- your pots are defective somehow and try to replace them
Joseph
737NUT
09-24-2010, 06:24 PM
It looks like you have the pot wired incorrectly. The PC is only seeing half of the pot. 1K, 10K, 100K makes no difference as long as hardware can handle the current increase.
Skylane
09-25-2010, 12:46 PM
The resistance does not matter that much for the pot is connected to +5 V (DC) and 0 V (ground) each at one end (so to speak). The PC (Analog to Digital converter) reads only the voltage from the slider of the pot... so a value between 0 and 5 Volts. The input impedance from the AD converter is so high, no current is flowing into the converter. The only current running is the current from the +5 Volt terminal to the 0 Volt terminal... so in case of a 100K pot 50 micro amps and in case of a 10K pot 500 micro amps.
However if you have (only once) connected the pot wrong and slided up/down, the pot will be permanentely damaged !!! and needs to be replaced.
737NUT
09-25-2010, 08:35 PM
The resistance does not matter that much for the pot is connected to +5 V (DC) and 0 V (ground) each at one end (so to speak). The PC (Analog to Digital converter) reads only the voltage from the slider of the pot... so a value between 0 and 5 Volts. The input impedance from the AD converter is so high, no current is flowing into the converter. The only current running is the current from the +5 Volt terminal to the 0 Volt terminal... so in case of a 100K pot 50 micro amps and in case of a 10K pot 500 micro amps.
However if you have (only once) connected the pot wrong and slided up/down, the pot will be permanentely damaged !!! and needs to be replaced.
Strange! When i switched to 1K pots, resolution was fine but the OC card i was using did get a bit hotter during use. I just guessed that less resistance=more current. Back to school for me. lol