ad: L-HROutlet
ad: l-assoc
ad: l-rl
ad: l-gcopper
ad: Subscribe
ad: L-rfparts
DK1IS Germany flag Germany

Login is required for additional detail.


Email: Login required to view

Ham Member Lookups: 10700


Hi, nice to see you on this page!

As far as I can think back I have always been enthusiastic about radio. Born in Hamburg at the end of 1948, as a schoolboy aged fourteen I became a member of the German DARC. In 1966 I got my license with the callsign DK1IS at the age of seventeen. From the beginning I was QRV mostly in CW on the HF bands with the usual periods of reduced activity due to study, job and family. I´m married and we have two grown sons. Since 1981 we have been living in Amberg, a town in Eastern Bavaria, about 60 km east of Nuremberg. After 17 years of working in the electrical industry I changed to the newly Amberg University of Applied Sciences in 1998 as a Professor of Electrical Engineering. Since 1999 I have been the dean of our faculty and since 2011 I´ve been a pensioner.

In 1999 DK1IS was the first LF station in Eastern Bavaria on 135.7 - 137.8 kHz. After moving in 2001 now I have much better possibilities to be active in that fascinating part of the spectrum. 23 countries worked on LF up to now: DL, F, G, GI, GM, HA, HB9, I, LX, OE, OH, OK, OM, ON, PA, S5, SM, SP, SV, RA6, UW8, YU, Z3 (mostly in DFCW). Since June 2013 DK1IS has been QRV on the 472 kHz MF band too. 19 countries worked on MF up to now: DL, EI, F, G, GM, HA, HB9, I, LA, OH, OK, OM, ON, OZ, PA, S5, SM, SP, 9H1 (real CW only). More information about this MF band see http://www.472khz.org/

Rig here:

HF: Kenwood TS-950SD, controlled by external GPS standard; Kenwood TS-50S (powered by solar cells plus accu).

LF, MF: Receiver RX1001, Exciter EX1001, both from Hagenuk, optionally controlled by external rubidium frequency standard from Rohde & Schwarz. Exciter running at 13.6 MHz respectively 4.73 MHz followed by a frequency divider for 1-Hz-steps on LF and 10-Hz-steps on MF. Homemade tube PA 2 x 4 x PL519 push pull class B, broadband transformer coupled, max. 800 W RF on LF and MF, plate efficiency 73% at 600 V DC. QRV in CW, QRSS, DFCW. Alternative exciter (most commonly used now): Frequency synthesizer MG 100 M from Schomandl, 0.1-Hz-steps for CW and DFCW up to 100 MHz, optionally controlled by external rubidium frequency standard too.

Additionally access via www to a remote RX site with Perseus SDRs and a lot of different antennas at our club station DL0AO (5 km away in a forest) - especially from LF to 10,1 MHz due to continually increasing local noise level. Since June 2016 there has been one more remote controlled SDR RX site on my garage, about 100 m away from my home and fed by a solar system, no utility mains. Selectable RX antennas there: active whip, earth dipole 42 m with four remote controlled grounding configurations and a rectangular horizontal loop 11 sqm right on the garage roof. Noise level up to 30 dB better than at home. Data transfer via a private 5-GHz-Ethernet-link.

Main antennas: Vertical helix 8 m for 7 - 30 MHz. Marconi-T, 13 m high, 33 m top load with 4 wires, 3 m wide for LF, MF and HF (on HF you rather may call it inverted ground plane), C = 660 pF, R = 30 Ohms, measured at 136 kHz respectively 12 Ohms at 473 kHz. Antennas remote selected and fed from the shack via 3 vacuum relais and 2 lines of RG 213, 25 m each. Autotransformer 50-30-12 Ohms for LF and MF. Additional active rod HE-011 from Rohde & Schwarz for reception.

Couplers: Harris RF-615B in the arbour ("tuning house") for HF. MF: remote controlled (by barbecue grill motor) Hagenuk-MF-variometer tuner 120 - 550 uH in the arbour plus additional homemade honeycomb loading coil for LF, L = 1.75 mH, Q = 540 with forced radial air cooling for long key down periods. Antenna current 5 A, antenna voltage 8.9 kV RMS measured at 136 kHz, 750 W.

Ground: 3 bare copper wires 6 m, buried 20 cm below the lawn with ground rods 1 m at each end + 2 ground rods 3 m + mains ground + water pipe system + all metal structures at the terrace side of the house.

Vy 73 es hpe to cuagn on the air!

Tom, DK1IS


Here are some pictures of my LF/MF station:


LF/MF Rack:
PA, PA power supply, RX1001, EX1001



PA, top view:
Vf/-Vg1/+Vg3 transformer, mains & TR contactors, RF compartment. Thermal management by
pressurised chassis, air outlet holes and thermo shields, transferring thermal radiation to convection.



RF compartment:
8 x PL519 with individual biasing, output transformer, thermo shields, air outlet holes and outlet
gaps around the tube sockets. Eurocent coins make good hubs for the plate connections.



RF compartment, bottom view, fan plate removed:
Lower middle: RF input transformer
Gray flat cable: control grid bias and cathode current sensor line for each individual tube
Upper middle: HV filter at center tap of output transformer



Power supply:
Vp 600V 2A DC, Vg2 180V 0.6A DC. Starter electronic due to inrush and charging currents.



LF/MF tuner in the arbour:
Variometer remote control (barbecue grill motor)



LF/MF tuner:
Variometer, radial cooled honeycomb LF coil, vacuum relais LF/MF/HF

Brown smoke at the feed through insulator from an unlucky former spider ...



LF/MF tuner, left side:
Autotransformer 50/30/12 Ohms, RF current sensor (gray box),
fan for radial cooling of honeycomb LF coil



Back side of arbour ("tuning house"):
Antenna disconnecting and earthing switch, pulse activated via thyristors
from a capacitor 3300uF charged to 200V DC (bird´s and cat´s bogle).

Hands off at switching or transmitting!



7622183 Last modified: 2016-10-10 14:59:13, 8486 bytes

Login Required

Login is required for additional detail.

You must be logged in to file a report on this page

Please login now...

QRZ Logbook Summary for - DK1IS
Latest Contacts for DK1IS at QRZ.com
dedateband mode grid Country op
UR5MIJ 2016-10-09 160m CW Ukraine Nickolay I. Poteryakhin
DL7RKK 2016-10-09 160m CW JO62pm Germany Peter kuhlen
OK1AY 2016-10-09 160m CW JN69no Czech Republic JOSEF BURIAN
AN400A 2016-10-03 40m CW IN73an Spain SPECIAL AWARD AND DIPLOMA
TZ4AM 2016-10-03 20m CW Mali Jeff Dorsey
DK3GI 2016-10-03 80m CW JN59lq Germany Roland Mensch
DL2DHS 2016-10-03 160m CW JO64sm Germany Joerg Pfeil
DJ3TU 2016-09-27 160m CW JN48tr Germany Norbert Bissinger
HB0/DL5YM 2016-09-27 160m CW Liechtenstein
DL7RKK 2016-09-27 160m CW JO62pm Germany Peter kuhlen
PE5ROS 2016-09-27 160m CW JO33bh Netherlands G. Gert Huizinga
UW2ZM 2016-09-27 160m CW KN57jx Ukraine Serge V. Yarovenko
DC5GD 2016-09-25 80m CW JN38VF87 Germany Albrecht Dietrich
V5/DK1CE 2016-09-23 40m CW Namibia
FM5FJ 2016-09-23 17m CW FK94nl Martinique Gil Joachim

Book Totals: 520 qso's   78 confirmed Get a free logbook at QRZ.COM

World Continents Award#14098
Granted: 2016-06-12 19:58:01   (DK1IS)

  • 20 Meters Mixed
  • Mixed CW
ad: giga-db
Copyright © 2016 by QRZ.COM
Sat Oct 22 03:29:42 2016 UTC
CPU: 0.136 sec 79070 bytes mp