Stll Chasing Erratic RPM

[snowyriver]

Regarding resistors in-line between Skyview and mags I'm up to 150 ohm. Have yet to fly with these installed. So what's the deal? Is the Skyview getting a stronger pulse as the rpms increase? Or is it the increasing speed that causes the need for stronger resistors? My rpm reporting is rock steady until about 2100 or so and then still makes constant jumps of 2,3,4, or even 1100 rpm! Back and forth. Craig

 

[preid]

What type of engine do you have? I had a similiar issue with the IO540- but the 100kOhm solved it. Steady now.

 

[snowyriver]

I'm running an 0360. I started with 35K and have used 75 and then 100K. Each one has helped some so I'm hopeful. I'm also hoping that the resistors are the issue and that there's not some other factor in this that I don't know about.

 

[jakej]

I'm running an 0360.  I started with 35K and have used 75 and then 100K.  Each one has helped some so I'm hopeful.  I'm also hoping that the resistors are the issue and that there's not some other factor in this that I don't know about.

PM me - I've done many Dynon installations with Lyc - 360's, never had to use anything other than the 30KoHm supplied resistors so i may be able to help here.

Jake J

 

[schristo]

The resistors are used to knock down the voltage coming from the mag to a much smaller value to be handled by the dynon to count pulses for rpm... From your description it sounds to me like a breaking signal. Check your connections and crimps carefully... the resistors are solid wire and can introduce erratic signals if not crimped perfectly... it helps to add stranded wire to the crimp and stabilize from vibration.

 

[dlloyd]

The indication on my O-360 also jumped around quite a bit untill I had a bad Slick mag rebuilt. Steady ever since.