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Default Datamarine wind instrument

"Lynn Coffelt" wrote
Yes, and yes. It's been a while, but in a prior life, did lots of
masthead rebuilds. Testing can be simple if you can find the "pinout"
(connections) on the connectors. (I don't have that data anymore)
The masthead speed unit is a sort of AC generator, and with a scope,
old analog multimeter, or even a pair of headphones you can see or hear

output of the generator while spinning the rotor by hand.
The indicator can be tested for basic function by driving the speed
input pins with a fairly low frequency square wave from a function
Big problem was having schematics of the connectors to see just what
pins were to be connected to the poor man's test equipment.
For a long time, Datamarine wind instruments used the same

and it was usually easy to spot a spinning Datamarine masthead unit on

same dock. Visit (with best manners, and maybe a couple of cool ones in
hand) and ask to hook up your instrument to his functioning masthead unit.
(power connections too)
Old Chief Lynn

Hi Lynn,
If I switch the head on/off several times quickly, I get a read out on the
windspeed. This 'may' say that the head is OK. The shaft in the masthead
unit is "sloppy" - I contacted DMI and they say that the bearing goes and
takes out the windspeed. They have a rebuild that costs $79.00. Probably
worth a try? I will open it up first and see what gives.

Thanks for the reply!