ISS - Mission Control Comm Check
Today's ISS crew schedule shows VHF comm checks from the Russian segment while over North America. Ground stations are at White Sands and Wallops.
The pass is from 20:00 UTC (west coast) to 20:15 UTC (east coast).
VHF-1 is 143.625 MHz FM, there may also be something on VHF-2 at 130.167 MHz.
Bob Christy
Note: When the VHF-1 transmitter is Running, the Amateur Radio receivers in the 2-meter band will go deaf (Receiving on 145, 490, 145.200, 145.990). This is because the Transmitting antenna for VHF-1 is less than 50 feet away from the Amateur Radio antennas.
The VHF-1 transmitter is usually left running for a few hours at a time for ground stations to test against. If you wish to test this theory, just try to ping the Amateur radio packet station ISS during a VHF-1 transmitter test.
When VHF-1 is transmitting, you will not see any packet activity, other than internally generated Beacons on 145.800 (down 145.800, uplink 145.990). When VHF-1 shuts down, normal packet access will resume.
Marex discovered this problem with the Mir Amateur Radio station. We then custom designed a filter by DCI, to resolve the issues. No such filter exists on ISS.
http://www.marexmg.org/documents/DCIFilterProject1.doc
WF1F, www.marexmg.org
--- On Wed, 7/14/10, Bob Christy bob@zarya.info wrote:
From: Bob Christy bob@zarya.info Subject: [amsat-bb] ISS - Mission Control Comm Check To: amsat-bb@amsat.org Date: Wednesday, July 14, 2010, 4:47 AM Today's ISS crew schedule shows VHF comm checks from the Russian segment while over North America. Ground stations are at White Sands and Wallops.
The pass is from 20:00 UTC (west coast) to 20:15 UTC (east coast).
VHF-1 is 143.625 MHz FM, there may also be something on VHF-2 at 130.167 MHz.
Bob Christy _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
A couple of corrections to Miles' post.
Packet is on 145.825 simplex.
VHF-1 does de-sense the D700 radio but not completely (I have see a station break through) but it takes a big gun to do so.
The VHF-1 transmitter is only planned to be keyed when in range of the US ground stations as indicated by the crew timeline (10-20 minutes depending on the orbit and number of ground stations in the footprint).
Kenneth - N5VHO
-----Original Message----- From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org] On Behalf Of MM Sent: Wednesday, July 14, 2010 7:29 AM To: amsat-bb@amsat.org; Bob Christy Subject: [amsat-bb] Re: ISS - Mission Control Comm Check
Note: When the VHF-1 transmitter is Running, the Amateur Radio receivers in the 2-meter band will go deaf (Receiving on 145, 490, 145.200, 145.990). This is because the Transmitting antenna for VHF-1 is less than 50 feet away from the Amateur Radio antennas.
The VHF-1 transmitter is usually left running for a few hours at a time for ground stations to test against. If you wish to test this theory, just try to ping the Amateur radio packet station ISS during a VHF-1 transmitter test.
When VHF-1 is transmitting, you will not see any packet activity, other than internally generated Beacons on 145.800 (down 145.800, uplink 145.990). When VHF-1 shuts down, normal packet access will resume.
Marex discovered this problem with the Mir Amateur Radio station. We then custom designed a filter by DCI, to resolve the issues. No such filter exists on ISS.
http://www.marexmg.org/documents/DCIFilterProject1.doc
WF1F, www.marexmg.org
--- On Wed, 7/14/10, Bob Christy bob@zarya.info wrote:
From: Bob Christy bob@zarya.info Subject: [amsat-bb] ISS - Mission Control Comm Check To: amsat-bb@amsat.org Date: Wednesday, July 14, 2010, 4:47 AM Today's ISS crew schedule shows VHF comm checks from the Russian segment while over North America. Ground stations are at White Sands and Wallops.
The pass is from 20:00 UTC (west coast) to 20:15 UTC (east coast).
VHF-1 is 143.625 MHz FM, there may also be something on VHF-2 at 130.167 MHz.
Bob Christy _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
_______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
participants (3)
-
Bob Christy -
MM -
Ransom, Kenneth G. (JSC-OC)[BARRIOS TECHNOLOGY]