Re: Ektelon Model H manual
If the model H is the same as the Neos, there will be a small hex-headed screw on the back side of the lock-out mechanism. You will see what looks to be a hole there and the screw is counter-sunk deep into this hole. I can't remember what size the allen wrench is, but any standard or metric allen wrench set will have the size.
Double clamp one end of the string from the calibrator. Lock the swiveling base in place. Hook the other end of the calibrator string into the tension head. Set the tension on the stringer to 60# as a good starting reference. Pull the tension until the machine locks out then take the reading from the calibrator. It should read 60#. If not, either unscrew or screw the adjusting hex-head screw and try again. Continue this til the reading is accurate at the pulled tension.
THEN, make sure to do so at 50#, 70#, and if you string any racquetball rackets, at 30 and 40# too. If you're machine is accurate at one tension, but is more than 1-2 pounds off at other tensions, you most likely need to have your machine head serviced. Keep in mind the 1-2 pound difference is still not a great reading, but it's manageable. It should be accurate at all levels, but sometimes the tensioning spring wears out.
Email me if you have questions and I can also take some pics for you.
Jeff Kupers, USPTA, PTR, MRT
*Fort Smith, AR