Printed QSL only via the bureau (preferred way) or direct. I DO NOT send or receive QSLs via internet (E-QSL, LoTW, qrz.com etc.).

My second valid call sign is OH4NPG. It is for my summer QTH and is mainly intended for 144 MHz 2kW PEP licence. I sometimes use OH4NPG also on HF bands from the summer QTH. See listing for OH4NPG. The QSL info above applies also to OH4NPG.

First licenced as OH2AXE for Finnish Technician class in 1971. Been on HF since autumn 2006.

Ham radio system at the moment:

1. HF equipment:

*** RX/TX: Elecraft K2 radio (#5744) with SSB, 160m, Transverter, digital audio processor, automatic tuner (QRP power) etc. plug-in modules (bottom right in pic above, the left one of the two dark boxes). *** Elecraft KPA100 (100W linear amp.) and KAT100 (100W autotuner) built into a separate EC2 enclosure (bottom right in pic above, the right one of the two dark boxes). *** 13.8V/33Amp linear power supply with temperature controlled forced air cooling for the above (own design - bottom right in pic above). *** Antenna: All band (160m - 10m), parallel doublet system with off-center feed (own design), 18 meters above ground. The 160 meter element is shortened to the length of 80 meter element with linear loading. The antenna has three wires on each side and the feed is through a 4:1 coaxial balun (home made, PA0FRI's design) and 600 ohm open wire line (home made). *** Fully isolated PC-to-Radio interface for data modes and SSTV (own design, built inside the K2 radio). *** PC: Old Compaq Deskpro (166MHz Pentium/MMX) running Windows 98SE (bottom left in the pic above). *** Ham software: MultiPSK (by F6CTE) for data modes, MMTTY (by JE3HHT) for non-ham RTTY, MMSSTV (by JE3HHT) for SSTV. ***

2. 144MHz equipment:

*** CW/SSB rig: Icom IC-202E (3W PEP/CW out - top, the upright one next to monitor in pic above) *** FM/packet rig: Yaesu FT-230R (3W/10W out - next to monitor under IC-202E in pic above) *** 13.8V/4Amp linear power supply for the above (own design - next to monitor in pic above) *** 144MHz linear amplifier with QQE 06/40 tube and linear tuned circuits (own design - top right in pic above). Output power over 100W with 3W drive. *** Power supply for the linear amp above (own design - right, under 144MHz amp in pic above). *** Antenna: 4 pcs Double Hybrid Quad, originally designed in the early 1970's by D. Roggensack (DL7KM) and optimized for 50 ohms and 2 x 2 stacking by yours truly in 2006 using MMANA software (by JE3HHT). 12 meters above ground. ***

3. Design projects:

Being an electronics designer, I have designed and built quite a few equipment and antennas during my ham radio "career" and documented many of them - some more accurately and others not so well - HI. For some of my designs, see the station info above. *** Currently I'm working on a simple HF power meter (from around 100mW to 1000W full scale in 10dB steps), which could be calibrated with a DC power supply - no second power meter required. This unit is not ready yet. *** I am also in the building stages for an all HF band (160 - 10 m), grid driven tube PUSH-PULL linear amp for 5 to 10 watts input (from the K2 radio) and output power over 1kW. It seems no-one has built a push-pull HF tube amp for years, so I have to see what's the problem - HI! The amp is going to have a pair of GU-74Bs (Pa=600W each) and tuned input. I've been stealing ideas for the amp from many sources, including F1FRV (http://f1frv.free.fr/), G3SEK (http://www.ifwtech.co.uk/g3sek/boards/tetrode/tetrode-1.htm), PA0FRI (http://www.xs4all.nl/~pa0fri/Lineairs/Frinear1500/FRI1500eng.htm), CQHAM.RU site (http://www.cqham.ru/cons_pa.htm - in Russian, but one can read the schematics - HI) etc. For the plate PSU I'll use my old home made 1250VAC/1.5-2A toroidal mains transformer (+1760V after rectification and filtering). The amp will have automatic control (at least mostly) with one or more PIC processors. ***Other on-going projects are a Dip Meter with digital frequency display (PIC based), a 1kW forced air cooled dummy load with a chip resistor and a digital (PIC based) L/C meter. All the designs for these are ready, but the units need to be built and software finished and tested. I'll need those for the amp project, so should try to get them ready soon. ***

Among others, I use the following programs for design work. Programs are running on Windows unless otherwise noted: *** Graphics (schematics, pc-board lay-out etc.): CorelDRAW ver. X4 (commercial/professional) and Inkscape ver. 0.47 (Linux) *** RF filter design: Elsie ver 2.34 (by W4ENE - www.tonnesoftware.com/elsie.html) and AADE Filter Design and Analysis ver. 4.5 (www.aade.com/filter.htm), both for general filter design, Tankit ver 2.0 (PA Tank Circuit design - by K8KK - www.radiok8kk.com/) *** RF toroid (and other coil) design: mini Ring Core Calculator ver 1.2 (by DL5SWB - www.dl5swb.de/html/mini_ring_core_calculator.htm) *** Antenna analysis: MMANA-GAL (by JE3HHT, DL1PBP and DL2KQ - http://mmhamsoft.amateur-radio.ca/) *** PIC Programming and simulation: PIC SIMULATOR IDE with floating point math (commercial but CHEAP - http://www.oshonsoft.com/) ***

If you are interested in any of my ham radio designs, drop me a line via E-mail. Eventually I'll try to add a listing here, when I get around to making one - HI. I can send you plans, diagrams or whatever information I may have available about the projects by E-mail. It will be free of charge for all ham radio operators, but with a requirement that the material must not be used for any commercial purposes without my signed permission.

73, OH2AXE