The Kreh Antenna Library is a grouping of numerous NEC antenna systems gathered by an avid CEM enthusiast Hartmut Hans and provided recently (2004) by Ursel Kreh.  In 2001, these were also provided to Bill Walker and available on a few NEC sites as the  DL5SAY Collection.  Hartmut Hans, DL5SAY, died of cancer in January 2001, aged 54.  He was a radio amateur with much experience, and in his profession he was a software development engineer for telecommunication devices.  During his disease he worked with the NEC (MoM) program, and developed many graphical applications including GNECX.  He was very proud of GNECX and the antenna models.  Some weeks before he died, he told Ursel that he wanted to finish these programs,  but the cancer was stronger.  Included herein are the original GNEC files along with the original NEC files from the wide assortment gathered by Hartmut Hans.  The antenna files and updated TCL files will also appear elsewhere on the site.

In the words of Ursel Kreh, "In international QSOs, he normally called himself Hart because of better understanding.  In March 1965, aged 19, he got his first callsign DL8ON.  Nine years later, still being a student, he gave back his callsign as there was no time and little opportunity for radio amateur activities. The callsign has since been given to an other radio amateur.  In August 1981, Hart applied for a license again obtaining the callsign DL5SAY (which he kept until his death)."  It was during this time that Ursel also participated.


"Hart\\''s enthusiasm concerning amateur radio was the technical aspect.  He bought good devices from Yaesu, and then he started to build further devices himself, e.g. a PA with 500 W and many small devices for the improvement of transmission etc.  The other passion concerning this hobby was to experiment with antennas.  At home he had a normal ground plane and also a butter nut he ordered from USA.  On many vacation trips the amateur radio equipment was part of our baggage, and each time he had new ideas in creating antennas with some "simple wires".  He had a very good feeling for antennas and resulting from this a great knowledge.  The biggest success was our vacation trip to Guadeloupe in October 1992 (with 15 kg equipment) where he threw a wire over the orange trees and where he got many pile ups."

"As Hart\\''s antenna at home had a big range, he had QSOs with people in the whole world, often with American radio amateurs, of course.  He liked to participate in contests and to distribute points.  Very often he only listened to the radio amateur traffic."

"In July 1997, we got the diagnosis of cancer.  In the following 3 1/2 years, we fought together for his life. These years have been full of hope and full of despair.  In this time he needed new purposes in life, and one was to work on antennas.  He spent much time on this.  In parallel, he trained for running, and with the cancer and with chemotherapy, he ran two marathons and several half marathons.  Hartmut died on 31st of January 2001. He was a wonderful person!"

"His whole amateur radio equipment including miles of antenna cables and lots of electrical components etc.  I have given to a small radio amateur club in our town. There are many young people, and the club has not much money, there was no club station, no antenna, etc. These people have been enthusiastic about the comprehensive and good equipment.  I am sure that Hartmut would be glad about my decision."

This antenna library page is dedicated to Hartmut Hans and Ursel Kreh and the extraordinary work and devotion they have both shown to the community.

krehLibrary.tgz (tar gzipped)

GNECX (gnecx1 or gnecx2) is written in TCL and needs the BLT library available on the Internet and possibly in your Linux/Unix distribution.  Several snapshots show this as a useful tool for analysis of NEC output files, which does not provide a graphical interface, results.




The results, animations, and analysis from the krehLibrary model files are included in the NEC Antenna Library section.