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This Week in Amateur Radio News for Friday 22 June 2018
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TWIAR via rec.radio.info Admin
Jun 22, 2018, 11:46:19 PM6/22/18
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via HACKADAY: Portable Ham Radio Design Fosters Experiments
Posted: 22 Jun 2018 07:26 PM PDT
https://ift.tt/2tdGbdd
[Charlie Morris] has been busy building a portable ham radio rig and
documenting his progress in a series of videos. You can see the first one
below. There’s four parts (more if you count things like part 4 and part 4a
as two parts) so far and it is always interesting to see inside a build
like this, where the choices and tradeoffs are explained.
The first part covers the Si5351 VFO and the associated display. There’s
very little to the VFO other than off-the-shelf modules including an
Arduino. You can also see the portable Morse code key which is actually a
micro switch. The second part experiments with audio amplifiers. [Charlie]
looked at the NE5534 vs discrete amplifiers. He was shooting for lowest
current draw that was usable. Other parts discuss the RF amplifier and the
receiver. Despite the VFO, there is quite a bit of non-module parts by the
time things start shaping up.
///////////////////////////////////////////
CAMSAT Offers More Details on New Satellites, One Carrying HF Transponders
Posted: 22 Jun 2018 07:26 PM PDT
https://ift.tt/2sZHkFi
CAMSAT, China’s Amateur Radio Satellite organization, has offered
additional details about the three Amateur Radio satellites it plans to
launch later this year. Two of the satellites, designated CAS-5A and CAS-6,
will carry transponders, and one of them will offer HF capability. CAMSAT’s
Alan Kung, BA1DU, told ARRL that the 6U CAS-5A will carry two HF
transponders and two V/UHF transponders. The plentiful equipment package
includes an H/T (21/29 MHz) mode linear transponder, an H/U (21/435 MHz)
mode linear transponder, an HF CW telemetry beacon, a V/U linear
transponder, a V/U FM transponder, a UHF CW telemetry beacon, and UHF AX.25
4.8k/9.6k baud GMSK telemetry.
///////////////////////////////////////////
Former Radio Amateur-Astronaut Named as Spains Minister of Science
Posted: 22 Jun 2018 07:26 PM PDT
https://ift.tt/2yfMLps
Amateur Radio operator and European Space Agency (ESA) astronaut Petro
Duque, ex-KC5RGG/ED4ISS, has been named as the Minister of Science in the
new Spanish government. Duque, 55, first went into space aboard the Shuttle
Discovery in 1998, and in 2003 he spent a week on the International Space
Station, carrying out Amateur Radio on the International Space Station
(ARISS) contacts with two schools in Spain.
Duque went to the ISS under a commercial agreement between the Russian
space agency and the ESA. He also conducted a series of scientific studies
during his ISS stay. Duque was Spain’s first astronaut.
///////////////////////////////////////////
via HACKADAY: The History and Physics of Triode Vacuum Tubes
Posted: 22 Jun 2018 07:26 PM PDT
https://ift.tt/2tsshnG
The triode vacuum tube might be nearly obsolete today, but it was a
technology critical to making radio practical over 100 years ago. [Kathy]
has put together a video that tells the story and explains the physics of
the device.
The first radio receivers used a device called a Coherer as a detector,
relying on two tiny filaments that would stick together when RF was
applied, allowing current to pass through. It was a device that worked, but
not reliably. It was in 1906 that Lee De Forest came up with a detector
device for radios using a vacuum tube containing a plate and a heated
filament. This device so strongly resembled the Fleming Valve which John
Fleming had patented a year before, that Fleming sued De Forest for patent
infringement.
After a bunch of attempts to get around the patent, De Forest decided to
add a third element to the tube: the grid. The grid is a piece of metal
that sits between the filament and the plate. A signal applied to the grid
will control the flow of electrons, allowing this device to operate as an
amplifier. The modification created the triode, and got around Fleming’s
patent.
///////////////////////////////////////////
ARISS-Russia Testing Undeployed CubeSats from ISS
Posted: 22 Jun 2018 07:26 PM PDT
https://ift.tt/2KcOTDf
ARISS-Russia is making FM transmissions on June 20 and 21 from two of its
Tanusha series of CubeSats, now aboard the International Space Station.
Russia’s ARISS organization has been developing the spacecraft in
collaboration with Southwest State University in Kursk.
Two earlier Tanusha CubeSats were hand-deployed by cosmonauts last August
and are performing cluster flight experiments through communication links.
Plans call for hand-deploying Tanusha 3 and 4 this August.
On June 20, Tanusha 3 was to be connected to one of the ARISS antennas on
the ISS Service Module to transmit greetings from students in several
languages on 437.05 MHz.
ARISS Russia is set to repeat the process on June 21 0730 – 1200 UTC on the
same frequency. The ARISS-Russia team also plans to retransmit these
signals on the standard ARISS 2-meter downlink, 145.80 MHz, using the JVC
Kenwood TM-D700 radio now on the ISS.
The next SSTV transmissions are planned for June 29 – July 1, with images
commemorating the various satellites the ARISS-Russia team has developed
and hand-deployed from the ISS. This will include SuitSat-1/Radioskaf-1,
deployed in February 2006. — Thanks to ARISS-Russia
///////////////////////////////////////////
via HACKADAY: Portable Ham Radio Design Fosters Experiments
Posted: 22 Jun 2018 07:26 PM PDT
https://ift.tt/2tdGbdd
[Charlie Morris] has been busy building a portable ham radio rig and
documenting his progress in a series of videos. You can see the first one
below. There’s four parts (more if you count things like part 4 and part 4a
as two parts) so far and it is always interesting to see inside a build
like this, where the choices and tradeoffs are explained.
The first part covers the Si5351 VFO and the associated display. There’s
very little to the VFO other than off-the-shelf modules including an
Arduino. You can also see the portable Morse code key which is actually a
micro switch. The second part experiments with audio amplifiers. [Charlie]
looked at the NE5534 vs discrete amplifiers. He was shooting for lowest
current draw that was usable. Other parts discuss the RF amplifier and the
receiver. Despite the VFO, there is quite a bit of non-module parts by the
time things start shaping up.
///////////////////////////////////////////
CAMSAT Offers More Details on New Satellites, One Carrying HF Transponders
Posted: 22 Jun 2018 07:26 PM PDT
https://ift.tt/2sZHkFi
CAMSAT, China’s Amateur Radio Satellite organization, has offered
additional details about the three Amateur Radio satellites it plans to
launch later this year. Two of the satellites, designated CAS-5A and CAS-6,
will carry transponders, and one of them will offer HF capability. CAMSAT’s
Alan Kung, BA1DU, told ARRL that the 6U CAS-5A will carry two HF
transponders and two V/UHF transponders. The plentiful equipment package
includes an H/T (21/29 MHz) mode linear transponder, an H/U (21/435 MHz)
mode linear transponder, an HF CW telemetry beacon, a V/U linear
transponder, a V/U FM transponder, a UHF CW telemetry beacon, and UHF AX.25
4.8k/9.6k baud GMSK telemetry.
///////////////////////////////////////////
Former Radio Amateur-Astronaut Named as Spains Minister of Science
Posted: 22 Jun 2018 07:26 PM PDT
https://ift.tt/2yfMLps
Amateur Radio operator and European Space Agency (ESA) astronaut Petro
Duque, ex-KC5RGG/ED4ISS, has been named as the Minister of Science in the
new Spanish government. Duque, 55, first went into space aboard the Shuttle
Discovery in 1998, and in 2003 he spent a week on the International Space
Station, carrying out Amateur Radio on the International Space Station
(ARISS) contacts with two schools in Spain.
Duque went to the ISS under a commercial agreement between the Russian
space agency and the ESA. He also conducted a series of scientific studies
during his ISS stay. Duque was Spain’s first astronaut.
///////////////////////////////////////////
via HACKADAY: The History and Physics of Triode Vacuum Tubes
Posted: 22 Jun 2018 07:26 PM PDT
https://ift.tt/2tsshnG
The triode vacuum tube might be nearly obsolete today, but it was a
technology critical to making radio practical over 100 years ago. [Kathy]
has put together a video that tells the story and explains the physics of
the device.
The first radio receivers used a device called a Coherer as a detector,
relying on two tiny filaments that would stick together when RF was
applied, allowing current to pass through. It was a device that worked, but
not reliably. It was in 1906 that Lee De Forest came up with a detector
device for radios using a vacuum tube containing a plate and a heated
filament. This device so strongly resembled the Fleming Valve which John
Fleming had patented a year before, that Fleming sued De Forest for patent
infringement.
After a bunch of attempts to get around the patent, De Forest decided to
add a third element to the tube: the grid. The grid is a piece of metal
that sits between the filament and the plate. A signal applied to the grid
will control the flow of electrons, allowing this device to operate as an
amplifier. The modification created the triode, and got around Fleming’s
patent.
///////////////////////////////////////////
ARISS-Russia Testing Undeployed CubeSats from ISS
Posted: 22 Jun 2018 07:26 PM PDT
https://ift.tt/2KcOTDf
ARISS-Russia is making FM transmissions on June 20 and 21 from two of its
Tanusha series of CubeSats, now aboard the International Space Station.
Russia’s ARISS organization has been developing the spacecraft in
collaboration with Southwest State University in Kursk.
Two earlier Tanusha CubeSats were hand-deployed by cosmonauts last August
and are performing cluster flight experiments through communication links.
Plans call for hand-deploying Tanusha 3 and 4 this August.
On June 20, Tanusha 3 was to be connected to one of the ARISS antennas on
the ISS Service Module to transmit greetings from students in several
languages on 437.05 MHz.
ARISS Russia is set to repeat the process on June 21 0730 – 1200 UTC on the
same frequency. The ARISS-Russia team also plans to retransmit these
signals on the standard ARISS 2-meter downlink, 145.80 MHz, using the JVC
Kenwood TM-D700 radio now on the ISS.
The next SSTV transmissions are planned for June 29 – July 1, with images
commemorating the various satellites the ARISS-Russia team has developed
and hand-deployed from the ISS. This will include SuitSat-1/Radioskaf-1,
deployed in February 2006. — Thanks to ARISS-Russia
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