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- wrote down a note in Finnish on the basic use of a coaxial balun and the advantages thereof (10.01.2010)
- OK, so I had to dive into some mechanical engineering (906k) in between, when my A1 laser printer simply failed on me, this time fortunately only a siezed electronic clutch
- putting together hardware for 122 GHz, but still need to build the mixers and devise some antennas too (15.09.2009)
- here you may find some notes on my 70 MHz OZ transverter that is waiting for the new Finnish 4 meter band allocation and some other related stuff, like using the FT897D with a transverter (30.08.2009)
- first 24 GHz amateur contact between Finland and Sweden - also new Finnish distance record ! (05.08.2009)
- test results for our SRAL national meeting DVB-T TX after aligment - in Finnish (04.07.2009)
- developed a nifty method for calibration and alignment of high stability frequency references using a Vector Network Analyser (02.07.2009)
- this is a link to the RATS Frequency Measurement Competition technical details page (in Finnish, 08.02.2009)
- the 2008 Nordic VUSHF conference was hosted by RATS ry and here is a video of the Construction Contest 10 GHz Receiver Reference Design (14.06.2009)
- some notes on AMSAT OSCAR 7 in Finnish and in English with Mode A and Mode B transponder block diagrams (07.12.2008)
- an article (in Finnish) about adding NICAM digital audio to analogue FM Amateur Television for the microwave bands (12.10.2008)
- an article (in Finnish) about FM-ATV over LASER experiments I did recently (now working on adding almost linear, digital NICAM sound too) (03.10.2008)
- had some ideas of adding an junkbox optical receiver (25k) to the OH2RTE Amateur Television Repeater of OH2HKE (28.08.2008)
- found some serious tin whiskers (64k) in the N(m) type connector of a small RF load in my hamshack (28.08.2008)
- a closer zoom to one of the longer whiskers tin whiskers (51k) and one very long one outside (86k) the outer coax shield (28.08.2008)
- another photo under different illumination brightness temperature and angle tin whiskers (104k) - pretty scary stuff... (28.08.2008)
- I often enjoy just listening to the different microwave beacons in
different propagation modes; OH3SHF
(6 Mb) on 10 GHz Rain Scatter and here is a longer
(11 Mb) clip (22.06.2008)
- a cool spectrogram shot of the OH3TR beacon in moderate rain 10 GHz rain scatter (160k) (28.08.2008)
- the broadband noise strip at around 0245UTC is the rising sun hitting
the beam - you can estimate the beamwidth for yourself ;-)
- the Moomin house got it's final roofing (151k) this summer with the kind help of Antti, OH2MNI (28.08.2008)
- a photo of the very serious 6 m mobile
antenna installation of OM Jan, OH1ZAA ;-) (19.06.2008)
- some notes on my first UWB
experiments - dissipating all RF in a 50 ohm termination of course
(17.06.2008)
- here is a photo of the Radio Amateur Technology Society Honorary
Member 2007 plaque - if you may call it such - oh yes, that crowbar
is solid titanium ! (17.06.2008)
- maybe somebody can make use of my notes on killing 98 % of my HF
interference with two smart moves (17.06.2008)
- a few notes on Passive
Intermodulation and the importance of torquing connectors, the 7/16
in particular - also with a VNA RL screenshot (17.06.2008)
- photo of my yet-to-be-finalized Ham Shack RF feedthrough patch
panel (17.06.2008)
- a new page dedicated to the radio polarimetric experiments of Dr.
Jiri Polivka
(05.12.2007)
- a new page focusing on receiving
signals from the JAXA Kaguya (Selene) spacecraft (02.12.2007)
- there is some very suspicious HF-stuff
taking place on the corner of my property...
- some notes
on my encounter with the Penzias - Wilson radiometer hardware at the
Deutsche Museum (11.11.2007)
- so just for the sake of archiving, some spectrum analyser plots of
the AO-40 satellite LEILA system constructed by S53MV:
- LEILA OFF
(9k), LEILA ON (9k),
how one of the LEILA notches (9k)
looks in the transponder passband
- Dr. Vladimir
Khaikin and his team detected a celestial source using a 30 GHz receiver
on the RATAN-600 - how narrow
can an antenna beam get ? (10.04.2007)
- a solar transit
plot with three of the 30 GHz receivers at the 600 m RATAN radio
telescope focal point, measuring the solar corona width (09.12.2007)
- 200 kHz wide optical
receiver with 24 MHz HF IF for the FT817 radio (built for OH1JJC)
(10.04.2007)
- rear
view of the optical detector/converter with IF output and DC input
(10.04.2007)
- also gave the man some
gain to put ahead of this receiver for our over-the-horizon tests
in the future using SSB/CW (10.04.2007)
- testing my equpment
on AO-51 when the
bird was in L/S mode with my dual
band 90 cm RHCP dish (10.04.2007)
- figuring out how to flexibly
get all 144 MHz - 47 GHz ham bands onto an EGIS/Nitec-JRC Robot
Positioner (10.04.2007)
- packaged
the fabulous SDR-IQ
(no affiliation) DSP radio into some recycled NMT900 mechanics - wish I
could afford, say, 10 SDR-IQ's ;-) (10.04.2007)
- cool stratospheric
clouds just before Christmas 2006 (10.04.2007)
- Lauha: washing the dishes,
taking an afternoon nap,
having a fun swing,
getting acquinted to the fine art of bakery,
enjoying the early spring sun
on lake
Kyynäröjärvi
(10.04.2007)
- lots of hard work in the background,
mind you... (10.04.2007)
- pulled together a local
control box for a special DVB-H dual amplifier, dual antenna
transmitter configuration - box under lab
tests and in operation
(10.04.2007)
- OK, so Pop recycled
the disposable Christmas decoration lights on Lauha's dolls house - here
is an overall view from the garden side (10.04.2007)
- Jukka, OH6DD
in Marburg in 1991 for P3D and Jari, OH3UW
in Marburg in 2006 for P3E (10.04.2007)
- some notes on an 11 GHz linear, low noise SatCom Esaki Tunnel
Diode preamplifier, in Finnish (12.03.2007). The unit sports 40 dB
gain and a NF of
approx. 6 dB (19.06.2008)
- Lauha: please
- no more paparazzi
!!! (78k) (30.09.2006)
- Lauha: How
was
breakfast ??? Ummmm - so and so... (65k) (30.09.2006)
- photo of the first AMSAT-OH X band HELAPS
transmitter (54 MHz -> 10451 MHz, circa 1994) (added 26.06.2006)
- Lauha helping
(85k) me out with the telephone extension... (04.05.2006)
- did the signal improve
(91k) any ? (04.05.2006)
- Lauha
Goes Mobile (105k) (20.04.2006)
- shot of the P3E satellite 21.7 -> 10.7 MHz IF downconverter/AGC
(90 dB gain/control range, 40 kHz wide, -5 dBm out) prototype
(108k) (20.04.2006)
- typical spectrum
plot (10k) of the IF converter output with an AGC controlled signal
being output (here set to - 15 dBm) (20.04.2006)
- photo from our X band antenna test
range (116k) (29.04.2006)
- same setup with OH2KXH
(121k) for size (29.04.2006)
- closeup of one of the experimental feeds
(73k) going
through ellipticity measurements (29.04.2006)
- a linear polarisation horn
(94k) for ellipticity assessment (29.04.2006)
- a simple shot of the the P3E S -> X band dual-mode
(analogue/coherent) transponder module
(108k) real-estate (06.01.2006)
- my simple 50 W solar
panel dump regulator (76k) before test installation (20.04.2006)
- some data on an ancient R&S SDB-M
(103k)
DVB-T modulator, that is beginning to come back to life in my shack
(04.04.2006)
- a photo of Lauha
(95k)
at 6 months of age, shot taken right after her elevenses ;-)
(20.02.2006)
- and a fun photo of
Mum
and Lauha (84k) in a multifeed session :) (21.02.2006)
- a topside photo of my AMSAT-OH P3E IF
combiner (111k)
matrix prototype (15.02.2006)
- bottomside
(125k) photo of the IF combiner prototype (15.02.2006)
- this module also draws 3 mA @ 12 V for an internal (hidden) CW
beacon carrier keying "HI" for test purposes
- IF inputs: 2.4 GHz, 1.3 GHz, 5.7 GHz, IF BPSK beacon, IF outputs:
10.4 GHz, 2.4 GHz
- my 2.5
kW/4.5 kWh UPS (87k)
system for the oil burner, circulation pumps, ham radio, fluorescent
lighting and PC server (31.01.2006)
- a wintry shore shot of Lake
Vesijako
(63k) in early December (04.12.2006)
- here is a winter
photo (60k) of
the dish waiting for the pedestal (08.01.2006)
- a couple of photos of The Dish Arrival one snowy winters eve: on
the truck
bed and another
with neighbour Pekka
Leppinen
watching on (01.12.2005)
- set my eyes on this 5.4 m
dish
almost 20 years ago...(photo 2,
photo 3,
photo 4,
photo 5),
last summer it was finally
pensioned :-) Surface accuracy good to 30 GHz (01.12.2005)
- been my kind of long-term dream as some of my buddies know; check
out
his birthday card from about 15 years back - front
and inside
(by Henry W. Majander®)
(15.12.2005)
- and Princess Lauha
now at the
age
of 3 months (24.11.2005)
- a photo of Anne and Princess
-
only four hours old ! (24.08.2005)
- some notes on microwave
scattering (21.08.2005)
- reworking the OH9VHF and OH9SHF beacons
(19.08.2005)
- the latest GME
development
- some info on a tracking
upgrade
for the Viestikallio OH2Z SCR-584 pedestal
- some small antenna experimenting
with AO-40 during orbit 1362 (17.10.2003)
- see end of this
page for Helsinki night
time laser experiments (17.6 km) (01.09.2003)
- added JA1ATI optical
communications
experiments page
- Finlands very first amateur DVB transmissions, more here
(04.05.2003)
- a piece of history: AO-21 audio
(453k) as received many years ago with a simple handie talkie and
rubber duck antenna
- a single image (128k)
of the G3RUH
9600 bit/s and higher modem for e.g. AO-40
- notes on modifying the XRF187S
FET
transistor from 950 MHz to 1.3 GHz (12.02.2003)
- added some photos of my KP11KK
satellite/radio astronomy/SETI experimentation site
- some notes on modifying surplus NERA PPL LO's
for millimetrewave use (in Finnish) (11.02.2003)
- some highly experimental (!) 2.4 and 1.3 GHz can feeds
for dishes :-) (10.02.2003)
- a compilation of the current Finnish microwave &
millimetrewave distance
records (24.07.2002)
- the OH2RTE ATV repeater
subpage (in
Finnish) (14.06.2002)
- a brief report describing my portable operation during orbit 728
(in Finnish) (02.06.2002)
- prototyping a 10.7 -> 30 MHz converter
for microwave noise temperature measurements (11.05.2002)
- some notes on using my 3 meter
Telefunken
dish on 2 meters - I just HAD to get into that repeater ! (in
Finnish) (07.04.2002)
- some photos of my F1EHN EME antenna
tracking
boards for controlling dish antennas (20.04.2002)
- dirt cheap C band waveguide
load for
use in a Dicke radio telescope front end (19.04.2002)
- astrospectrometry with Jorma Ryske (see Optical Projects for
more): Vega
(17.04.2002)
- some new info on a 10 GHz band
polarimeter
for detecting solar flares (near bottom of page) (17.04.2002)
Updated 10.01.2010
