John Smith wrote:
"Do you happen to have a URL handy where I could view "Bulletin 74?"

I searched the web unsuccessfully, including some NIST sites which
dictated schedules for clearing their files at certain file ages. But, I
did find a reference to the famous bulletin in Keith Henney`s 1950
edition of "Radio Engineering Handbook". On page 132, Keith writes:
"It is possible to calculate the true (l-f) inductance of some types of
air-cored coils with a fair degree of accuracy. National Bureau of
Standards Circular 74 has long been the most authorative source of such
information. Some of the most useful contained therein are reproduced
here."

Pages of information follow which include design charts which I can`t
reproduce due to my limitations. Such information is not copyrighted as
it is assumed the taxpayer has paid for collection of the information
already, and should not have to pay for it a second time. That was pre
Bush policy, of course.

You can probably borrow a copy of Keith Henney`s book in a library near
you and delight ijn designing your own antenna coil. The publisher was
McGraw-Hill.

Best regards, Richard Harrison, KB5WZI