Wagner Rudder Angle Indicator

[Top Hatt Craig]

Hi All, we have a Wagner 150 with a bad pot in the "follow up" it's a Bourns 3859A-AD4-102A that Bourns says is obsolete.Digikey recommended a 3851A-282-102BL but the spec says it's a one turn pot (280 degrees) and our pot sees almost 2 turns stop to stop.Would anyone know if I should look for a 1K ohm pot that's capable of more turns? I see 10 turns is popular, this is a cost no object repair.Thanks, Craig

 

[drburke]

I am a little mystified why your linkage gives you 2 full turns from something made for 280 degrees.

If truly the case, you need 500 ohms per turn, and can use "only" two turns from a 20K 10-turn pot.

DAN

ps Hey Craig--you are nearby; we can talk about it offline or I can take a look!

 

[Top Hatt Craig]

Thanks for your reply, the pot Digikey recommended based on their notes searching the original part number is a 1K ohm one turn pot, I don't know how many turns our pot was because it spins freely without stopping.The nearly two turns stop to stop is the result of the geared mechanism attached to the rudders that moves a lever through an approximate 180 degrees. I don't mind trying a few pots to find the best one.We live in San Jose, regards Craig

 

[drburke]

Hi Craig,

Call (510) 847-4619 and we can talk about Rusty

DAN

 

[SEVEN]

Take it easy on me Dan.

 

[chuckbullett@gmail.com]

Take it easy on me Dan.

This is my balliwick totally. Firstly, let me check our new-old-stock at KCBS when I return to work on Friday.If it is a precision pot you desire it's possible to set up the range you want with some outboard resistors too, using the new pot as your "fine" resolution control. I'm flying into Maine today- I hope to be back for next weekend.RegardsChuck B; Chartmaker

 

[Top Hatt Craig]

Turns out the 1K ohm single turn Potentialometer Digikey recommend was the correct one. Like the one I removed, it also has no mechanical stops so cannot be damaged. I had a local machine/fabricator shop neatly drill the roll-pin hole through the 1/4" shaft on the pot and installed it with the linkage centered and the indicator reading zero. Works great.