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Posts: 133
I have tried to program the latest start switch with servo from Karl.
I have used the setup from message 18605 but I am totally lost an unable to get it to work. I have tried both setups with and without placeholder..
My servo is in 12 o'clock position as a zero point and I want it to go anticlocwise to around 8 o'clock position when N2 is about 55% (when start valve open light) goes out)
It will then turn start switch to off.
Then stay in that position ( and block starter switch) until you shut down and/or N2 is below 30% for so to return to the 12 o'clock position.
I have also tried the MF solution from Carl but he is using different Offsets and I am unable also to get this to work.
Anyone able to help with this setup.
2021-08-29 23:27
From: ETSI, Germany
Posts: 5501

The servo should NOT block the Switch..... Thats the Key of the whole thematic.
If it remain in the 8 oclock Pos then you will kill the Servo if you make a misstake and turn the starter back to GND whatever the engine is still running.

About Karl.
At first his Offsets are different. He not use PMDG..... He fly with ProSim.
But the main theory is the same!
By the way..... Karl use a Solonoid.... So he not need to move the Shaft back like a Servo..... He simply unpower it.
After see a lot of attempts from multiple users i will say..... Solonoid is the best solution. Servo works, but with lots of disadvantage. More difficult, more expensive, less stable and not a real feeling !

Your Servo must move in the moment when Engine Start Switch is moved in the Sim..... AND it should move back shortly behind.
If you use a Solonoid.... Same logic.... Work when Sim Switch is moved and disabled shortly behind.
NEVER remain in the OFF Position.... Best way is it turn back / go off in the same second !

Solution: the only needed indications are : Virtual Swtich position (Offset 64FC and 64FD ) and the N2 Value of the left/right engine.

Both Ways ( solonoid or servo) use for the moving action the Virtual switch ..... GND (0) means in Waiting position ..... OFF (1) means servo must move to 8 o clock or solonoid must Push.
With the N2 we build a "Window" when the Mechanic is controled by the Virtual Switch position..... Out of that window it is always neutral.... Means the Solonid is unpowerd and the servo is on the 12 o clock position.

If i remember right from Stephan he uses N2 greater then 40 and less then 54.
So below 40 means e.g. if Aircraft is on the gate qwithout engine start ( Value 0) . So the Mechanic get "armed" only a view seconds before the switch is moved finally.
Above 54 means the Switch movemnet have still happend and the engine is now running in IDLE. So on that point the Solonoid can get off or your servo can move back to 12 o clock.

If you can not solve this with my informations... We need to talk on Discord !
Good Luck !
2021-08-30 08:42
Posts: 133
You are partly right.
Karl has now both solutions, the newest one is with servo.
I have also build the one with solenoid but find it hard to get enough power to reset the swith with the solenoid that Karl recommend, so therefore i would try servo..
I am uncertain what the 0 and 1 refer to, is it flight sim value or output value.
I think I must have problems with the precondition because I have problem to return the servo to 12 o'clock position after N2 has passed 55 %.
I have used the setup exact from message 18605.
Can that be that while I am waiting for new 8 pos rotary that I use the old starter switch to engage starter and the new switch with only the servo???
Are you able to send me the setup on discord hrings#2221 or do we have to talk
[Last edited by hrings, 2021-08-30 11:40]
2021-08-30 10:03