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Extra 3 position switch
Posted: Sun Mar 11, 2012 5:27 am
by wojtek76
Does anybody know how to replaced 2 position switch with 3 position switch?
I need for my configuration 2 x 3 position switches.
Thanks.
Re: Extra 3 position switch
Posted: Sun Mar 11, 2012 6:11 am
by pmackenzie
You will either have to combine two 2 position switches into on 3 position one, or possibly replace a pot with a 3 position switch
The use the custom switches to produce the 3 settings you need.
You could also leave the two 2 position switches in place and use the custom switches to combine them into a 4 position switch.
Pat MacKenzie
Re: Extra 3 position switch
Posted: Sun Mar 11, 2012 8:20 pm
by man-bis
wojtek76 wrote:Does anybody know how to replaced 2 position switch with 3 position switch?
I need for my configuration 2 x 3 position switches.
Thanks.
Such a mod can be done as shown here:
Re: Extra 3 position switch
Posted: Sun Mar 11, 2012 8:45 pm
by pmackenzie
That is probably the best way to do it.
You could also leave the pot in and add a SPDT switch to select either the centre tap of the pot or the centre terminal of the switch as the input to the mcu.
One way the pot would still work, the other way the 3 position switch would work.
Pat MacKenzie
Re: Extra 3 position switch
Posted: Sun Mar 11, 2012 10:51 pm
by jhsa
there's only one problem.. you would have the resistors in parallel with the pot
Re: Extra 3 position switch
Posted: Sun Mar 11, 2012 11:32 pm
by pmackenzie
All the pots in the transmitter are in parallel between Vcc and ground, you are simply adding one more set of fixed resistors
The added switch will choose between the pot and the switched voltage divider
Pat MacKenzie
Re: Extra 3 position switch
Posted: Mon Mar 12, 2012 12:43 am
by jhsa
true.. didn't think about that..
Re: Extra 3 position switch
Posted: Wed May 16, 2012 1:42 am
by wojtek76
man-bis wrote:wojtek76 wrote:Does anybody know how to replaced 2 position switch with 3 position switch?
I need for my configuration 2 x 3 position switches.
Thanks.
Such a mod can be done as shown here:
Thank for help.
I replaced pot3 as you show me on picture, but something is not Wright. Switch only switch to high,low,low. Any clue what could be wrong?
Re: Extra 3 position switch
Posted: Wed May 16, 2012 4:47 pm
by jhsa
You could try something like this.. Just an idea.. Don't know if it makes any difference..
On the other picture the switch was shorting one of the resistors leaving only 2.5k between 5V and GND.. This way it replicates the values of the pot at the middle and end points.. Sorry about my English
João
Re: Extra 3 position switch
Posted: Wed May 16, 2012 9:23 pm
by MikeB
Looks good to me.
Mike.
Re: Extra 3 position switch
Posted: Thu Jul 26, 2012 9:15 am
by flyboy
Can we replace a 2 position switch to 3 position with this mod?
Re: Extra 3 position switch
Posted: Thu Jul 26, 2012 10:09 am
by Kilrah
No.
Re: Extra more position switch
Posted: Thu Jul 26, 2012 10:17 am
by HC1969
New idea:
Multi-function switch.
Each steps can be on a different function.
Re: Extra 3 position switch
Posted: Thu Jul 26, 2012 10:19 am
by Kilrah
Yep that's a common use for the guys who use Ardupilot. A 5-position rotary switch with a resistor ladder on an analog input
Re: Extra 3 position switch
Posted: Tue Nov 27, 2012 11:53 am
by Outbreak
jhsa wrote:You could try something like this.. Just an idea.. Don't know if it makes any difference..
On the other picture the switch was shorting one of the resistors leaving only 2.5k between 5V and GND.. This way it replicates the values of the pot at the middle and end points..
João
Hi i have a question.. in my city i couldent find 2.5k ohm resistors.. but i found 2.2k ohm. if i try to do it with 2.2k ohm resistors, will it work ?
Re: Extra 3 position switch
Posted: Tue Nov 27, 2012 2:53 pm
by jhsa
I guess it will work but to be safe I would go for 2.7K. Maybe you can find them better as they are more a standard value than 2.5K
João
Re: Extra 3 position switch
Posted: Tue Nov 27, 2012 3:01 pm
by Outbreak
what can be the danger of using lower k and higher k ?
Re: Extra 3 position switch
Posted: Tue Nov 27, 2012 3:37 pm
by jhsa
Higher K, no danger at all.. lower K, if it is to low will draw more current from the voltage regulator.. in this case I think it is not a big difference, but don't forget that all the pots are in parallel, and if you lower one of the values to much it could make a big difference.
Normally we have seven 5K pots in parallel on the 9x being fed with 5V.
that means a parallel resistence of 714 ohm. the current draw of the parallel is 0,0070A. 7mA
If you replace one of the pots with 2 times 2.2K, it makes 4.4K, so, then we have 6 pots of 5K plus 4.4K in parallel.. that is 700 ohm
the current is then 0,0071A, 7.1mA.
As you see there is not much difference in current consumption.. I guess 2 times 2.2K is fine then
I would still try to find the 2.7K
João
EDIT: Made a mistake on the calculations
Typical with me.. SORRY
The difference is only 0,1mA. corrected now
Re: Extra 3 position switch
Posted: Tue Nov 27, 2012 3:44 pm
by Outbreak
Awesome explanation ! im gone look for 2.7k . hope i can find.. its so hard to find those stuff in my country
i asked many places but all i could find is 2.2k.. but didnt ask more then 2.5 so mybe they have.. i will see tonight
Tnx alot
Re: Extra 3 position switch
Posted: Wed Nov 28, 2012 6:56 am
by Outbreak
I found 2.7k and made it.. switch is working awesome.!! tnx alot jhsa
Re: Extra 3 position switch
Posted: Wed Nov 28, 2012 10:44 am
by jhsa
wonderful..
Have a beer..
Re: Extra 3 position switch
Posted: Sat Dec 08, 2012 3:36 pm
by omegamanuk
Outbreak, any chance of posting a photo of what you have done?
I need todo this for my FY31AP which needs 2x 3 position switches.
Re: Extra 3 position switch
Posted: Mon Dec 10, 2012 7:34 pm
by omegamanuk
Ok got some 2.4k resistors and a couple of three way switches and followed the dig above and sucess!! Had my douts as when I switched on although the display screen showed the switches functioning , when I tried my plane it was dead, whiped the radio in bits and tried the connections to the FRSKY module and its all working may resolder those just to be safe. Thanks for the help youve all posted.
As a picture paints a thousand words here you go.
Re: Extra 3 position switch
Posted: Mon Dec 10, 2012 11:32 pm
by alib
are you in the uk? if so, where did u get the resistors from?
Re: Extra 3 position switch
Posted: Tue Dec 11, 2012 7:06 am
by omegamanuk
Yes from uk , got the switches and resistors (2.4k) from maplin
Re: Extra 3 position switch
Posted: Tue Dec 11, 2012 7:13 am
by Rob Thomson
I have suggested a feature on open9x to allow you to swap P3 with a switch.. In this fashion.
The idea being that you loose P3 on the mix list, but gain 3POS2, ID3, ID4, ID5
This bin theory could make programing easier as you do not then need multiple custom switches!
Sent from my Nexus 7 using Tapatalk 2
Re: Extra 3 position switch
Posted: Tue Dec 11, 2012 7:59 am
by Kilrah
Just a thing, P3 is the most conveniently placed when you need to use a pot... So it would be wise to rather sacrifice one of the other 2
Sent via mobile
Re: Extra 3 position switch
Posted: Tue Dec 11, 2012 8:13 am
by Rob Thomson
No issue to me which one....
I suggested P3 because it was the simplest to drop off the list of mixes.. without noticing it missing
Maybe a feature could be to allow the user to set the pot to use for 3POS2 ?
Rob
Re: Extra 3 position switch
Posted: Fri Dec 28, 2012 11:48 am
by hobeeami
Works great. I needed a 3 way switch to setup the bank options on an IKON FBL control.
Re: Extra 3 position switch
Posted: Mon Jan 21, 2013 8:04 pm
by KanishkaRC
hi,
I had a quick look at the code and I guess open9x should work without having any modification with this configuration, only thing needed is simple display option as I understand. but first off let me admit I am not a pro..
as in code,
int16_t getValue(uint8_t i)
{
/*srcRaw is shifted +1!*/
if(i<NUM_STICKS+NUM_POTS) return calibratedStick
;
and according to the feature list,
new source in Mixers: 3POS which returns -100% / 0 / +100% depending on the 3 position switch of the 9x
just to check this hypothesis can anybody who had done this hardware modification, pls check this hex file to see whether it works as it supposed to be ?
only mod is P3 now shows as 3P... which means 2nd 3 pos switch..