there is a member on my website who has a Jacobs machine
who has a great deal of info on this machine.
he is a real neat Guy who loves to talk wind power.

he goes by the user FoxTrot70

JMK, the interview was taken in 1973. By then mr. Jacobs was already 70 years old. If he were alive today (I don't know if he is) he'd be 104 years old now.

Luckeydog, thanks for the info. I'll be contacting FoxTrot70 soon.

Here's another interview, this time with someone from NASA, doing a major windturbine project in the mid '70s. It is in stark contrast with the work of Jacobs. It's not an enjoyable read, but it is illustrative...

http://www.motherearthnews.com/Alternative-Energy/1976-05-01/The-Plowboy-Interview-Donald-Cooksey.as px

I tried looking up the final report of that NASA windturbine but couldn't find it. Actually, I found it, but it's not available on-line. Unlike Sandia the NASA charges $$ to get a chance to read the report:

http://ntrs.nasa.gov/search.jsp?R=306903&id=3&qs=N%3D4294877489

If I read it right his system uses a ring/pinion gear combo - like the automotive differential he used in his kid-on-farm design - to send the power toward the ground as shaft rotation.  And he does his furling by a flyball/spring governor controlling blade pitch, allowing him to use a fixed tail (except for "shutdown furling").  Differentials are easy to convert but the governor would be a pain.

I'd thought of using a differential like this previously, but had dismissed the idea because the torque on the drive shaft would tend to turn the blades away from the wind.  But the fact that he made it work got me thinking again:

 - With enough of a ratio the torque would be small.
 - The gear ratio also improves things for the generator.  B-)
 - The tilted-tail-pivot furling system requres a nontrivial yawing torque to operate.

In reply to where you can find usefull illustrations concerning the Jacobs wind turbine.

May I suggest the following titles from two wind energy "guru's" which can be obtained by the international inter-library service.

"The Homebuilt, Wind-Generated Electricity Handbook" by Michael A. Hackleman
Earthmind, Peace Press - ISBN 0-915238-05-5  - Lib. of Congress cat. nr. 75-36307
California USA 1975

This book is mainly concerned with the dis-assembly and the re-building of the
JACOBS and WINCHARGER 1930's small household-size wind turbines.

Alone Michael Hackleman's section on tower erection is more than worth a carefull study.

Likewise a good drawing and photograph of the JACOBS governing mechanism may be
found on page 136 of "Wind Power" by Paul Gipe - James and James - ISBN 1-902916-54-9
London UK 2004.

Stew Corman from sunny Endicott

Thank you for the fascinating interview.  Several quotes made me sit up straight:

"I developed a brush made up of a layer of graphite, then carbon, then graphite, then carbon."

"We licked that one by developing what we called our "reverse current relay". "

I'm currently sitting at my office desk with the electrical schematics of a 1950's helicopter spread out beside me.  I just realized that this helicopter regulates its own engine-driven generator with field coils stimulated through a "reverse current relay", just as Jacobs describes.  

"The bearings themselves were pretty good, see, but the seals around the races would dry out and let the grease inside get away after a few years."

Another thing I've encountered in some helicopter components.  Sealed bearings AREN'T.  Some things never change....

"...it's not very smart to completely stop a windplant propeller. The ice mostly freezes on the lowest blade and that'll wreck your plant if you turn it loose. It's much better to let the propeller swing around a little bit during a winter storm."

Q: "What if an individual wants to go out and build his own windplant the way you put your first ones together...with materials he finds in junkyards and other odds and ends?"
JACOBS: Well I haven't been active in the field for 15 or 18 years now. There's a lot of new stuff I'm not familiar with...but I'd say that some of the AC generators and the rectifiers now available should make that pretty easy. "