Born in may 1958. My profession is engineer in mechanics.
In 1974 started as a SWLwith a Grundig Radio, later a Centruy 21 follewed by a  JRC NRD 515. I was then ONL7048.  Using long wire antennas and a full size wire loop for  60m band, listening to broadcast station on that band.

In 1984 licenced as ON4ADZ, intrested in dx ing cw and ssb. 
In 1992 I archieved 5BWAZ: the last zone needed was 29 on 7.0 MHz.

Worked all DXCC countries in SSB and confirmed.
Worked all DXCCcountries minus 1 (P5) in CW and confirmed.
Worked 329 current DXCC 's in RTTY,   280 confirmed  including P5.

Operating in RTTY since 1999.
RTTY contesting highlights as ON4ADZ or OO4ADZ: first EU in the cq/rj ww rtty 2005, first EU - 3th World in wpx rtty (2004 and 2005), first in WAE RTTY in 2005.
As ON4CT :  in 2012 WPX RTTY  2th EU/4thWW, in 2016  9th EU.

Other contests as ON4ADZ : IARU HF CHAMPIONSHIP SOAB MIX LP: 2005 8thWorld Wide,
as ON4CT : IARU HF SOAP CW LP  :  2006 6thWW, 2007 4thWW, 2008 5th WW

In March 2006 new call: ON4CT.

My toys: Yaesu FTdx5000D with 300 Hz roofing filter installed.
Antennas: Cushcraft X7 for 10/15 and 20m bands at 25m, Optibeam rotary dipole for 40/30m band at 27m, Inv V for 80m apex at 23m, 160m: tower loaded with yagi and 2 elevated radials feedpoint at 6m.
For the 12 and 17 m bands, I use the Inv V or X7.
All antennas are fed with ECOFLEX coax , eco10 or eco15.
Antennas are switched by a homemade 4 to 1 box, using Siemens VR421 vacuum relays (see pictures below).

Previous transceivers: ICOM 740,Kenwood TS850 and a FT1000MP MkV.

Rotor:yaesu 2700 sdx mounted on the concrete tower base (pictures below) , replaced the bulb on the control unit by blue leds (pictures below)

General Logging: LOGGER32 with the MMTTY engine, (freeware).  With thanks to JE1MMT for devlopping the RTTY software.
Digital-cw and voice keying: homemade interface between TX-PC.
Contest logger: N1MM+ software (freeware) contesting in ssb, cw and digimodes.    With thanks to Tom, N1MM and crew.

My log is regulary updated on CLUBLOG,  qsl s for ON4ADZ and ON4CT can be requested via that website to.

LOTW user,  this log is up to date untill  20 JULY 2017.

73

DIRK ON4CT (latest update 30 may 2017)

stress analyse of my free standing tower topload with two antennas at 160km/h windspeed , 1 unit = 1kN/cm