In article ,
Channel Jumper wrote:

But I figure the Ring is probably 9 inches too shot - if the ring is 7.5
inches in diameter and needs to be 10 and the stub is too short - if it
needs to be 18 inches long and is only 6....

Channel Jumper-

You can get parts measurements for the various Ringo antennas at the
CushCraft website (Now part of MFJ!). For the Ten Meter version,
http://www.cushcraftamateur.com/Product.php?productid=AR-10. A user
manual is available by clicking on "AR-10 Downloads". I do not see a
Stub length given for the AR-10, but the AR-6 manual has a chart.

The AR-10 manual's specification says that gain is 3 dB "Ref.
Quarterwave"!

Fred
K4DII