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MicroHellas
08-16-2008, 11:46 AM
Hello,

I'll appreciate a lot if someone helps me to understand the difference between a rotary switch and an encoder. For my first eye seems that a rotary switch has limit positions (max 12?) while the encoder has unlimited (?).

My main problem is that I don't know if I must connect a rotary switch to encoder ports of IO Inputs card or not?

And how a can restrict a rotary switch to a specific nbr of positions? eg I want to use it with 5 only positions.

Thank you
Maria

dnoize
08-16-2008, 05:45 PM
kalispera maria.

physically rotary switches and rotary encoders are totally different components.

basically a rotary switch is a switch in a rotary form factor: you dont toggle a lever up and down but rotate a knob to switch between different terminals.

what makes it confusing is the fact that rotary switched (which have a limited number of positions) can be transformed into a unlimited number of positions to be used as rotary encoders with the opencockpit software/hardware. This way you can use them as rotary encoders directly on the mastercard (without the need of the encoder card).

If you want to use them as a switch and want to limit the number of positions: under the mounting nut there is a ring with a pin. You can change the position of this pin to fall into a number of holes. each hole represents a stop. this way you can make it stop after x number of positions.


A rotary encoder is NOT a switch. but gives pulses. basically it tells your iocard to count up or down. rotary encoders are available in a wide variety of sorts and the open cockpit cards only accept a very specific kind directly to their master card. However their encoder card accepts a much wider range of encoders, including opticals. this encoder card translates the signal of the encoder to a understandable signal for the master card.

Hope this helps.

Stef

ian@737ng.co.uk
08-17-2008, 01:31 AM
yassoo captain.......
i had a similar problem (but not with OC cards) and this is how i sorted it.
http://www.737ng.co.uk/simple%20encoder.pdf
this may help you work out what you have to do.
have a great week and best regards from wales... ian

MicroHellas
08-17-2008, 04:01 AM
yassoo captain.......
i had a similar problem (but not with OC cards) and this is how i sorted it.
http://www.737ng.co.uk/simple%20encoder.pdf
this may help you work out what you have to do.
have a great week and best regards from wales... ian


Yasoo Captain with Website:D

Well, believe it or not, I've visited your site 2-3 times last week. Don't know how I found it, but it really contains many usefull information.

Keep up the good work Ian

Maria

MicroHellas
08-17-2008, 04:18 AM
Hope this helps.

Stef

Goede dag Stef :D

Sure it helps. But please let me repeat it to be sure that I understood it;-)


Rotary switches have predefinied number of positions. Also, if I understood well, the number of positions are depending on the angle of each step. eg if the angle is 30o then there are 12 positions, if the angle is 45o = 8 positions.
I can use rotary switches for anything with limited options eg Magnetos, Flaps but not for Frequencies like NAV etc where I must use encoder.
A Rotary switch can be modified to have unlimited positions? HOW? :D
I can add a rotary switch to any position in IO Inputs card so I can save the 4 only positions for encoders (Bad luck for me, just yesterday I ordered a 2nd input card just for this reason).
And finally... I've seen that there are double (?) encoders. I mean like in MCP. Double encoders for my poor English are "A knob inside a knob. A smaller at the top, a larger at the bottom". :roll:

That's all .....for the moment ;)
Yassoo from Greece ... do you like to send you some Sun as exchange for your help?:rolleyes:

dnoize
08-17-2008, 05:45 AM
Goede dag Stef :D

kalimera





Rotary switches have predefinied number of positions. Also, if I understood well, the number of positions are depending on the angle of each step. eg if the angle is 30o then there are 12 positions, if the angle is 45o = 8 positions.

thats correct for the stock consumer grade rotary switches. In custom rotary switches as in real aircrafts it can be different. the number of positions in consumer grade switches can usually be modified as described in my previous post.



I can use rotary switches for anything with limited options eg Magnetos, Flaps but not for Frequencies like NAV etc where I must use encoder.
unless you modify them. you can even make dual concentric encoders out of them.



A Rotary switch can be modified to have unlimited positions? HOW? :D

To be clear: number of positions (clicks) will be the same but you will be able to turn them on and on and on....like an encoder.

here is a few tutorials:

http://www.opencockpits.com/modules.php?name=Content&pa=showpage&pid=10&page=1
http://www.opencockpits.com/modules.php?name=Content&pa=showpage&pid=9

If you dont need the dual concentric or the push button function its even easier. You only need to open the switch, take the stop out (cutting away a little plastic tab) put them together again and wire them correctly (how to do that is described in one of the open cockpit manuals).

Alternatively if you dont want to go through the hassle:
opencockpit sells dirtcheap single rotary's with push for a couple of euro's
another user in this forum is selling cheap dual concentrics with push that work with opencockpits encoder card.



I can add a rotary switch to any position in IO Inputs card so I can save the 4 only positions for encoders (Bad luck for me, just yesterday I ordered a 2nd input card just for this reason).

the only thing you have to keep in mind that all inputs you want to trigger with one rotary switch need to share the same ground. so inputs and ground need to be on the same group. This is for the OC mastercard. The groups are listed in the manual.



And finally... I've seen that there are double (?) encoders. I mean like in MCP. Double encoders for my poor English are "A knob inside a knob. A smaller at the top, a larger at the bottom". :roll:

actually thats what it is. both driving a seperate encoder.
What aircraft are you building ? as a 737 (what is what i am working on) does not have dual encoders on the MCP. It does have however (even worse to source) a combination of a encoder in the centre (smaller knob on top) and a switch for the outer (larger) knob. You find this in the bankangle knob.
The EFIS has similar constructions (although they work differently again in the real aircraft)



That's all .....for the moment ;)
Yassoo from Greece ... do you like to send you some Sun as exchange for your help?:rolleyes:

Please do, allthough i prefer the yearly trip to my country of origin :-)

Stef

MicroHellas
08-17-2008, 06:36 AM
What aircraft are you building ?

...hehe... That's the point. What I'm building now are only plans to start building a cockpit:rolleyes:

Well, haven't decided yet. As I seen 95% of builders are going to 737-800NG or Airbus. I can understand it as there are lots of accessories out there. But to be honest I want to try-out my limits even if I'll face lots of problems. Finally is just a hobby. I like B717 and AVRO RJ 100 (Jambolino).

Any good suggestion is always welcome:D

Maria

dnoize
08-17-2008, 11:54 AM
Well, some people forget, but planning is the most important part.

717 is nice but wonder what to do with glass displays/fmc software....
something you have to take into consideration too.

same for the avro RJ.

Unless you decide to program the software yourself

btw... few days late, but happy nameday ;-) chronia pola ;-)

Stef

MicroHellas
08-17-2008, 12:10 PM
btw... few days late, but happy nameday ;-) chronia pola ;-)

Stef

If I understood well, are you Greek? ..lol... Then Stef=Stefanos?
In any case, thank you for your info and for your wishes too. Never is late.

Maria

dnoize
08-17-2008, 01:08 PM
you understood well ;-)

born and raised in the netherlands, but from greek origin.

Stef(anos) :-)

ian@737ng.co.uk
08-17-2008, 02:23 PM
yassoo maria....
happy name day from me too..... xponia pola!
rgds ... ian

mabderezai
02-03-2011, 02:05 AM
Hi ...
I was wondering if anyone had a sample code for taking a rotary encoder directly into the mastercard... I am not use how one can avoid using an encoder card.

Thanks!