Hi,I just finished my first Vertical Speed Indicator (VSI). Full handmate and I'm proud at it as it is my first attemptEarlier I already had build the Servomodule from FSBus and already had played with it. At that moment I thought that a normal servo had a turn-angle of 180 degrees. Because this VSI has an angle of 300 degrees I have used a gear-ratio of 24 to 12 so the 180 of de servoshaft would be 360 on the needle. So far for the theory...after a lot of work and sweating these days, today I tested this VSI and it came to me as a suprise that the shaft of the servo just turns a 100 degrees instead of the expected 180. So the needle didn't get far enough on both sides. I played a couple hours with the parameters of the FSRouter-Servo but I didn't get the good result.Two questions:1. Does a normal RC-servo has a turnangle of 90 or 180 degrees? A friend of me ownes a RC-car and there the turn-angle is also +/-100 degrees in spite you can turn the shaft manualy 180 degrees like mine does.2. Does somebody knows witch parameters you have to used for a full turn-angle within the FSBus-Router (for the VSI-parameter)? At this moment I use Multiplier: 0.016Offset: 122Min: 0Max: 255The test-slider give me just a turn of +/- 100 degrees max.Hopefully somebody can help me with this because otherwise I have to change the gear-ratio witch means I have to change a lot.With this some pictures of the VSI. It shall be used in a F16A (block 5) sim.GreetzWerner

Hello,Normal servo have about 190

Werner,That's a very nice looking VSI! Mikewww.mikesflightdeck.com

I find it had to believe that the restriction to a servo rotation of 100

Sure that the servo is not limited to 100

Hi,I contacted Dirk Anderseck because if anyone could give me a good answer on this then it must be him. Here is his answer:The angle is indeed restricted in the current servo controller. I will overwork that to overcome the bounds andmake it a bit more stable.The old controller is not able to handle the time critical pulses good enough. I will replace it by a fully interrupt driven ATMEGA. I will make that, when i build the 3 standby instruments in my 737 cockpit.So, looks that I have to wait, change the gear-ratio or make a switch to IOCards. Thanks for the replys and for the complimentsGreetzWerner

Thank's for the explanation ...Other question where do you buy the gears you used ?BOB

Hi Bob,see Topic #17141 for the gear-question.GreetingsWerner