Hello and welcome to this section of my homepage, which is dedicated to my hobby Amateur Radio.
My name is Matthias Bopp and I am a German ham radio amateur, holding my respective license and callsign DD1US since 1979.
I am a member of DARC (Deutscher Amateur Radio Club) and AMSAT (the Radio Amateur Satellite Corporation).

I used to work mostly on VHF / UHF / SHF frequencies but since 2003 also operate sometimes on the HF bands.

Below you can find some pictures of my "Shack". That's how radio amateurs call their room with the equipment, which includes in my case transceivers for various operations modes like ATV, FAX, SSTV, FM, SSB, satellite communication and Packet Radio. As radio amateurs have the privilege to build their equipment (e.g. receivers, transmitters, amplifiers and antennas) on their own you can see that I also have a lot of test equipment.

The propagation conditions are different on the various frequency bands and vary over time. They are a function of a number of parameters like the status of the ionosphere.

The link on the left shows a map with the Maximum Usable Frequencies (MUFs) for 3000 kilometer radio signal paths. The map also shows the present grayline and other important features for long distance contacts (DX).

Especially on HF but also on VHF and sometimes on UHF the magnetic field of the earth has a strong impact on the propagation of the respective waves. One of the associated phenomena are reflections at Aurora zones which can influence the propagation of radio waves and provide DX conditions. On the right please find a link to present magnetometer data and predictions of the Aurora probability in Germany. The further the cursor is moving to the lower right corner the higher the likelihood for an Aurora.

Amateur Television (ATV) was one of the operating modes I like most. I used to build most of my equipment myself. Shown in the photograph below is my home-brew FM-ATV dual band transmitter (for the 1.2 and 2.4 GHz bands).

During the operation via my local ATV-repeater DB0PE I received the ATV signal at 1.2 GHz using a long Yagi and transmitted my live video ATV signal at 2.4 GHz using a segment dish antenna from Connifer. To allow full-duplex operation the repeater featured an additional 435MHz voice input. I used one of my omni-directional multi-band stacked ground-plane antennas for this input. Unfortunately DB0PE is no more operational in ATV and thus I have presently no more opportunity to operate ATV.

In the pictures above you can see my present VHF/UHF/SHF antennas which are mostly omni-directional aerials

Sometimes I am also using repeaters here in the area. Most of them are for voice but some are also for Packet Radio or ATV. If you want to contact me you can see in the table below, which repeaters I can access from my home and in which of the various operating modes.

10m FM repeater
 

2m FM repeater
 

70cm FM repeater
 

23cm FM repeater
 

ATV repeater
 

Packet Radio digipeater
 

The next map shows the location of the above listed repeaters with reference to my own location. This map was generated using the excellent Freeware program "Radiomobile". Please note that the full resolution map which you get when clicking on the picture below is 3 MBytes large and the download may take some time.
 

If you are not in my area and thus cannot reach me directly or via one of the repeaters listed above we could also try to get in contact using "Echolink". This is a technology which links amateur radio repeaters via the Internet and thus allows worldwide contacts. In addition it also provides the possibility to access the repeaters from any PC with a Internet connection. Access is only available for radio amateurs holding a valid license. My node numbers are 63949 for my callsign DD1US and 518482 when operating my simplex Echolink gateway.

Many people think, that Radio Amateurs use only the short wave (HF) frequency bands. I guess this is based on the historical use of Amateur Radio as a low cost medium to talk to friends all over the world as well as an efficient wireless system for emergency cases. Not very long time ago private world-wide communication was not very common as long distance phone calls were very expensive.

Today people can use a simple Internet connection to talk to friends all over the world almost free of charge. However it is still fascinating to use the HF bands with their specific propagation characteristics. On the right picture you see a part of my antenna system for the HF bands. The antennas are mounted on a mast which can be rotated 360°. The 3-band dipole is used for 10m, 15m and 20m and on top is a 4 element Yagi for the 6m band. I use the 3-band dipole also to receive the russian satellites with HF downlinks. In addition I also use a W3DZZ wire dipole for 40m and 80m bands. I use an ICOM IC-735 transceiver with approx. 100 Watts output power. I am not very active on the shortwave bands but if you are interested I will be happy to arrange a sked.

When using the 4 element Yagi (extended HB9CV antenna) on 50 MHz very nice contacts are possible. The 6m band is sometimes called the "magic band" because all of a sudden very strong signals from stations far away come up and disappear just as fast shortly later. Clicking on the little map below left you can see a larger map, which will show how many contacts and countries can be worked during one afternoon with reasonable good conditions on 6m (example data are from June 27th 2004). Actually my contact bridging the longest distance during that day is not shown, because it was outside of Europe: it was a QSO (contact) to the East coast of the USA to W1FC (>6000km distance).

I live in a small village in a valley, which is surrounded by hills in most directions. You can see more details of my terrain if you click on the 3D picture to the right (north is up). Unfortunately those hills block my transmissions at low elevation angles and thus I am handicapped with respect to terrestrial communication at very high frequencies (UHF and SHF). This is one of the reasons why I became very fond of satellite operation using the various OSCAR (orbiting satellite carrying amateur radio) and RS (russian satellites) satellites. Operation via those satellites built by radio amateurs around the world is possible by transmission of voice (SSTV, FM), morse code (CW), data transmissions (packet radio) as well as still pictures (FAX) and slow scan television pictures (SSTV).

 Satellite communication is challenging because many parameters of the ground station have to be controlled carefully and simultaneously. The signals of the low earth orbiting satellites (LEOs) can be very strong, such that communication even by a hand held portable transceiver using an omni-directional antenna is possible. However some of the satellites have a highly elliptical orbit and in apogee the satellite is approximately 40000 km away and thus the signals can be also very weak.

Therefore directional antennas and low noise receivers have to be used. For me it is one of the rewarding areas to build and optimize the ground station. On the right picture please see my antenna system which I used to have for satellite operation. It is presently taken down for renovation of the room but planned to be put up again in the near future. On this photography you see (from left to right) a 2m X-Quad antenna, a 13cm helical antenna, a 23cm helical antenna array and a 70cm X-Quad antenna. The antenna system can be rotated both, in azimuth and elevation, manually or fully automated by a satellite tracking program running on a Windows PC.

To be able to appraise the system sensitivity regularly test signals with well defined power levels (called ZRO tests) used to be transmitted by the control stations. During these tests Morse code was transmitted and the signal of the satellite was attenuated precisely in 3 dB steps until the signal was very weak (level 9 means 27dB below the regular level of the satellites beacon). I spent some time to optimize my station and was finally able to receive down to level 8 using very small antennas (the 2m and 70cm X-Quad antennas you can see on the picture above).

On AO-10 and AO-13 ZRO transmisions were conducted both, 2m (145 MHz) and 70cm (435 MHz) band. If you would like to listen to such a ZRO transmission you can click on the picture to the right. This image is a visualization of the audio signal with frequency increasing from left-to-right and time bottom-to-top. You will hear the ZRO transmission from Andy McAllister conducted on 2m band on April 24th 1993. The sound track is 6 minutes long and contains continuous data, starting with ZRO level 8 (CW signal 24dB below the beacon) including level 9 (-27dB) and level A (-30dB) signal, finishing with the "End of Test" message at full power. Many thanks to Darrel AA7FV for this record.

Another aspect of the ham radio hobby can be to try to reach as many stations in other countries or continents as possible. One can apply for various diplomas confirming the achievement of certain criteria. Furthermore there are regular competitions called contests, when individual ham radio operators or whole groups try to make as many contracts to stations as far away as possible in a given time.
While I am not very fond of diplomas and contests I applied for one which is shown on the left. A friend in Zimbabwe arranged it while travelling to different locations and operating via AMSAT Oscar 13.

The present status of all Amateur radio satellites can be found on the Homepage of AMSAT. Please click on the AMSAT picture on the right to see this excellent summary in English language.

A table with a summary of recent reception records is provided by David Carr KD5QGR. Please click on the icon on the left to access this page. If you receive satellites yourself please also submit your report on this page, thanks !

N2YO provides a web based satellite tracking tool which calculates the present locations of various satellites and includes a nice graphical display. If you click on the picture on the right you can access his program online and get real time data based on always up-to-date keplerian elements.

Most recently I started to operate an APRS internet gateway. My gateway feeds digital signals, which are received on VHF from various satellites (including NO-44, NO-60, NO-61 all on 145.825 MHz) as well as the ARISS experiment of the international space-station ISS (145.800 MHz) live to the internet. This enables the control stations and other interested people to monitor the traffic and the telemetry of the satellites while they have no direct access to the satellites as they are above other parts of the globe. The more gateways are operated, the better the coverage. You can access the worldwide collected data by clicking on the picture to the left. It is also possible to use the uplink of the satellites to communicate online with other Ham Radio operators.

The various AMSAT groups worldwide are continuously looking for support for their next generation programs. This can be actual support in building satellites or components or a financial support of the projects.  

One of the next major projects which is presently in preparation by AMSAT in Germany is P3Express. As this will be a satellite in a highly elliptical orbit it will allow the users worldwide contacts. AMSAT needs also your support and if you would like to donate to this program please visit the dedicated website www.p3e-satellite.org. You will receive a nice gift card like the one shown on the right.

Furthermore I had various contacts to the cosmonauts and astronauts in the space stations MIR, the US Space Shuttles and the International Space Station ISS. Below please find some examples. An extensive collection with historical sound tracks related to Satellites, Space ships and Satellite Communications is available in the "Sounds from Space" section of this website.

Following a contact (QSO), ham radio amateurs exchange (QSL) cards for the confirmation. On the left you can see such a card which I received from the space station MIR. On the right you can see my own QSL card.

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In October 1994 Dr. Ulf Merbold, DB1KM, stayed 4 weeks onboard the space station MIR participating in the "Euromir 94" mission. I had the chance to talk to him on 2m. If you would like to listen to part of my contact with Ulf, using the callsign DP3MIR, please click on the button at the left.

During the mission "Euromir 95" Dr. Thomas Reiter, DF4TR, stayed 6 months onboard the space station MIR. During this time he was also active in Amateur Radio using the callsign DP0MIR. I had 4 voice contacts with Thomas using FM simplex mode in the 2m band (frequency 145,975MHz). The first audio file was recorded on October 4th 1995 around 6 am UTC. The second file was recorded during another contact some days later.

For some time the Ham Radio equipment onboard the MIR space station was configured as a voice repeater. If you would like to listen to a contact with Torsten DG7RO operating at the club station DL0TZ please click on the button at the left.

If you like, you may have a look at some pictures I received directly from the MIR space station in December 1998. The transmission was Slow Scan Television (SSTV, sub mode Robot). During the first two pictures the camera was directed out of the window showing part of the space station. The 3rd picture shows the crew operating the HAM radio equipment.

Meanwhile the ham radio equipment onboard the International Space Station (ISS) is also activated and in October 2002 I had a first voice contact with cosmonaut Valery G. Korzun, Expedition Five mission commander. On the left you see Valery using the amateur radio equipment in the functional cargo block (FGB) of the ISS.

If you are interested, where the international space station ISS is presently located and whether you may be able to listen to its transmissions or watch it in the twilight, the picture to the right shows you its current location.

 (courtesy of ESA&Heavens-Above) 

In addition the link below will get you to a simulated real time view of the Earth, as if watched through the round window of the US Destiny Lab on ISS. Please note that quite often you will only see the blue ocean as Earth is mo stly covered by water.

As you probably already noticed based on the descriptions above I am very interested in Space Communications overall. Therefore I decided to add a page with historical sound tracks related to Satellites, Space ships and Satellite Communications. I hope you will enjoy browsing it. Please click on the picture on the right to access these pages which I named "Sounds from Space".

In spring 2008 we started a restructuring of our home and I had to remove all coax-cables from my shack to my antennas. Therefore I built a little portable setup to be able to listen to various satellites when sitting in our garden. Even after completion of the renovation I kept the setup comprised of the following antennas which can be attached to a little tripod: an omni-directional antenna covering the frequency range from 0.5-1500 MHz, a logarithmic-periodic antenna covering the frequency range from 800-2000 MHz and a helix antenna covering the frequency range from 2000-2600 MHz. All antennas have adequate low noise amplifiers directly attached to them and the AOR AR-8600 all-mode receiver covers the full frequency range 0.5-3000 MHz. The amplifiers as well as the receiver feature integrated rechargeable batteries and thus the setup is operational within seconds.

Another very interesting mode is Faxsimile (FAX). Here, besides ham radio operation, also the reception of polar orbiting weather satellites (LEOs) is possible. I built the necessary FM receiver (shown on the left side). With this receiver and my 2m X-Quad antenna I receive the automatic picture transmissions (APT) of the NOAA and Meteor weather satellites at 137 MHz and decode it with the sound card of my PC. The complete station is running fully automated and is controlled by a PC.

If you click on the icons below you can see some of the weather satellite APT pictures which I received. Behind each of the icons is actually a little collection of pictures.

METEOR 2-1

NOAA12

METEOR 3-5

NOAA14

NOAA15

If you want to listen to such APT transmissions, please click on the receiver icons below. You can learn more about such transmissions on my page "Sounds from Space".

Russian
METEOR
weather
satellites

US
NOAA
weather
satellites

Starting 2006 I built up a little portable station in our summerhouse. I am mostly using this little station to monitor the bands and occasionally also operate on the upper HF bands (10m and 15m). Please click on the picture to the right to get to this page showing the setup and examples of operation logs.

In January 2010 I started a new job and now have an additional home in Freiburg/Breisgau. In my loft house which is located downtown Freiburg I presently only operate a little portable station using FM on 2m/70cm/23cm. You can find some more information about my portable station when clicking on the view of my house on the left.