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Receiving K6BEN in south San Francisco bay area
For those viewing NASA-TV on the Internet, video stream has minute or two delay.
Audio Re-transmission on 145.585 MHz:
Audio portion of NASA TV was retransmitted on 145.585 MHz (simplex).
NASA-TV schedule in PDF or XLS format for up-to-date info which includes mission events, see http://www.nasa.gov/multimedia/nasatv/mission_schedule.html
Daily schedule at http://www.nasa.gov/multimedia/nasatv/MM_NTV_Schedule.html
Launch schedules at http://www.nasa.gov/missions/highlights/schedule.html
Schedule of NASA TV during Shuttle Missions http://spaceflight.nasa.gov/realdata/nasatv/schedule.html
Streaming video of NASA TV at http://spaceflight.nasa.gov/realdata/nasatv/index.html
Image showing diagram of re-transmission system
STS-114 launch video captures:
These images are from a VCR in a home in San Jose that taped reception of K6BEN. Reception tend to be good and bad. These are not pristine commercial, broadcast quality, sugarcoated, ideal, etc. These are actual received images of video received with a home VCR, uncut, direct from NASA with all the techie stuff in between. There may be hum bars or smudges due to interference of linked repeater signals (ATV does not interfere with linked repeater signals, it is the other way around). Other stations in the south bay may not see this interference.
Below are miscellaneous footage transmitted prior to launch of shuttle preparations showing control console for tracking cameras, installation of a C-band radar, handsewing of thermal protection material in the nose cone, and installation of the rudder onto Discovery. A good illustration of the large numbers of people involved.
Photos of the media at Ames during STS114 mission (click here)
STS-114 Website:
http://www.nasa.gov/returntoflight/main/index.html
Ames Wind Tunnel Test Results:
Our wind tunnels were in the media spotlight just after a series of tests of damaged thermal blankets in air flows. Click here for some images from NASA-TV via the K6BEN-ATV repeater.
For more on the wind tunnel facilities that performed tests on the thermal blankets, see http://windtunnels.arc.nasa.gov
SRB Video Stills: A fascinating view from the SRBs during launch. A videofile may be added to this site later.
Click here for SRB video captures.
Re-transmission equipment:
A photo gallery was made showing our setup here at the AARC. Click here for photos.
We updated our station equipment:
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| Equipment used for retransmitting NASA-TV. | Re-location of Videolynx 1.2GHz video transmitter | |
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| ATV uplink and downlink antennas. | ATV uplink and downlink monitors. |
Here is the equipment used for retransmitting NASA-TV video and audio. The large TV set is connected to Ames Vidnet and a composite video is sent to a video titlemaker. Output of the video title maker is connected to the small rackmount monitor on the left and that monitor’s output is connected to the VideoLynx Z23B transmitter (small beige box on right). This transmitter delivers 2 watts to a loop yagi antenna. A VCR is tuned to the K6BEN-ATV output and viewed with the small rackmount monitor on the right.
The rack behind the TV set contains a 50 watt transmitter for the 145.585 MHz audio retransmission.
Other items seen in this photo is a smaller TV/VCR tuned to another NASA channel that would show other feeds such as Florida weather maps, however, mostly it is regular NASA-TV we use to tape specific broadcasts. Rack on the left are video processing equipment (excess government property) acquired by the AARC. This rack contains a vectorscope and a timebased corrector that cleans up the video sync pulses and color levels. Professional broadcasters use equipment like this for quality video transmissions.
Image showing basic diagram of the ATV network, click for enlargement.
Image showing diagram of re-transmission system, click for enlargement.
This is the 1.2GHz loop yagi antenna aimed at the K6BEN video repeater site. Video capture of this same antenna is below. The UHF yagi antenna is aimed at the K6BEN-ATV repeater site.
Here is a 2 meter J-pole antenna for the 145.585 MHz audio retransmission of NASA-TV. Probably the best VHF antenna, it was built by the American Legion Post 380. They constructed and sold many of these in past years but unfortunately no more. Not only are the American Legion J-pole antennas effective radiators, the SWR is virtually 1.0 with no reflections. Recently, this antenna was raised from 25 feet to 40 feet AGL.
I monitored the K6BEN repeater output with this VCR and TV set in my office. The antenna is a custom design by Walt KK1CW.
Evaluation:
During June 2005, tests were done with a 1.2 GHz video transmitter and a loop yagi antenna for uplink to the hilltop K6BEN-ATV repeater. Downlink signal was taped and video captures were made to illustrate the results seen below. Some areas in south bay get better reception, AARC shack is in a high RFI noise area and TV sets are vunerable to RFI. Other stations reported the video uplink signal to be very clear (P5 picture). Our reception at the AARC shack that is a little less that P4.
The 1.2 GHz loop yagi antenna owned by Walt (A6JT) narrowly escaped destruction during a cleanup. Antenna was mounted on the existing VHF/UHF antenna mast. Some of the rings were bent but were restored. This video capture on the right of an evaluation transmission shows the antenna.
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