Posts Tagged ‘SSTV’
More SSTV from the ISS
The SSTV activity had been due to last three days starting on Saturday but commencement was delayed by the NASA space walk.
Receiving the signal and decoding is relatively straightforward due to relatively high power used (around 25W) however getting a perfect image is a challenge and dependant on a number of factors.
- The timing of the overhead pass. Due to the time taken to transmit the image and the three minute delay between each image it is possible to only be in reception range for the end of one image and the start of the next.
- The ISS is moving quickly and so the transmission suffers noticeable Doppler shift. FM is more immune to the effect but for optimal performance adjustment of the tuned frequency is required especially on high elevation passes (more information).
- The ISS moves position, both in direction and elevation as it moves across the sky and will show up the peaks and troughs in a static antennas radiation pattern. This leads to bands of noise when the signal level falls. The use of a rotatable (and if possible tiltable) antenna (or even an handheld one) is the dirigour mode of operating satellites (and the ISS) for serious enthusiasts.
- Noise and local interference will also obviously affect the image.
Mission Control |
I opted a two pronged approach, the Yaesu FT857D connected to my rotatable four element YAGI which is mounted horizontally for SSB and the old TRIO/KENWOOD TR9000 was connected to the X50 dual-band collinear mounted vertically.
I had two copies of the MMSSTV program running on separate laptops The TR9000 was left running largely unattended tuned to 145.800MHz, while the FT857D was tweaked to the optimum frequency while the YAGI antenna was rotated to the correct azimuth during the pass.
All adjustments were done manually and I use the Orbitron program for prediction and under the Rotor/Radio tab the frequency and azimuth are shown and updated during the pass (as can be seen in the screen show below)
I missed the first low elevation at 11:07UTC, but was able to monitor and decode images on all the remaining passes during the day, with some excellent results, the images show the full images decodes on both radio set ups as a comparison.
FT857D - Yagi |
TR9000 - Collinear |
FT857D - Yagi |
TR9000 - Collinear |
FT857D - Yagi |
TR9000 - Collinear |
FT857D - Yagi |
TR9000 - Collinear |
FT857D - Yagi |
TR9000 - Collinear |
I was especially pleased when one of my best images was featured on the Amsat-UK and the Southgate Amateur Radio News websites.
What was slightly worrying and it also happened during the last SSTV activities were some operators transmitting on the downlink frequency even during a pass, what sounded like someone keying up was responsible for the single noise line on another perfect image. I even received an unexpected SSTV image, complete with a call sign while the system was waiting for the next pass. I won't publish it here as everyone makes mistakes.
The experiments are continuing today but I am in work so will just leave an automated set up running on the collinear.
Judging by the messages on social media these SSTV activities seem to have captured the imagination of a lot of operators and several members of my local club South Kesteven Amateur Radio Society (SKARS) had their first go with some excellent results and are hooked! The images can seen on the SKARS Facebook page
Long may the activities continue, hopefully started to transmit some live images from space.
LHS Episode #121: Freudian Linux
It’s the first episode of 2014, and we start the year off right: by talking about philosophy. Say what? Yep, that’s right. Trust us, it’s a lot more entertaining that it might at first sound. We have a special guest on the program, Ted (WA0EIR), who brings a through-provoking topic with him. Then we have a bunch of the usual suspects, including short topics on Linux, amateur radio, science and more. There is even feedback, info on our Indiegogo campaign for Hamvention and our Raspberry Pi giveaway. Don’t miss it!
73 de The LHS Guys
Show Notes #102
Episode #102 Audio (Listen Now):
Introduction:
- Rob from the MintCast podcast is on the show tonight filling in for the nomadic and enigmatic Richard.
Announcements:
- The 2013 Dayton Hamvention is coming up May 17-19 in Dayton, Ohio. We are still in need of donations. Please keep ‘em coming.
- The Wouff Hong Podcast, member of the Black Sparrow Media Network, have released their first episode. If you don’t subscribe to the BSM aggregate feed, you can find them at the link above. Good episode, and they mention LHS.
- Rob and Russ use BeyondPod on Android as a podcast manager.
- Roy, KK4ATD, will be in Atlanta at RARSfest as an ambassador for LHS. If you’re anywhere near Raleigh, NC on Saturday, March 30, 2013, stop by and say hello. [LHS will NOT be present at RARSfest this year. Sorry for any confusion. -Ed]
- The sponsored ads in the right column of the LHS web site actually make us a not insignificant amount of money when you click on them. If you want to help us out without donating your own money, please click on an ad when you visit our site. We get money in our donation box, and you don’t lighten your own pockets. Thank you!
Topics:
- Visit KE8P’s blog. One of the articles documents using a Raspberry Pi as a temperature monitor.
- KK4ATD has developed Hamux, a 64-bit, CentOS-based Linux distribution with ham radio applications. This is a “live” CD image, so you can boot it from CD and try it before installing. At 698MB, it just barely fits on a CD.
- Our hosts embark on a brief digression about Douglas Adams.
- Slow Scan TV (SSTV)SSTV is a method of sending still images using radio frequencies on the HF bands. FSTV (fast-scan TV), which is typically done on VHF and UHF frequencies at distances up to a couple hundred miles, is similar to broadcast TV.In order to operate SSTV, you’ll need a radio (and a license to transmit), a computer, a sound card interface to connect them to each other, and software. For Linux, we have QSSTV. The current version is 7.1.7, released on January 4, 2012. It is compatible with the Ham Radio Control Libraries (hamlib) for controlling the radio.Russ gives a brief overview of the various configuration options and interface of QSSTV.
- Rob is not a ham, but has considered obtaining his license. Unfortunately, he lives in an area with deed restrictions that prohibit outside antennas. What are his options? There are several resources on the web for ham operation with antenna restrictions. Some of these are:
- http://www.stealthamateur.com/
- http://www.g4ilo.com/stealth.html
- http://www.iw5edi.com/ham-radio/?attic-antennas,131
Though in Rob’s case, with aluminum foil-lined roof tiles, attic antennas are not likely to work very well.
Other possibilities: using EchoLink, IRLP, operating mobile or portable. Perhaps tossing up a temporary wire antenna in the back yard, operate, then take it down.
Rob and Russ discuss the various options, potential for TVI, and VEC testing opportunities.
Feedback:
- David, KE0AZ, writes to say he’s sorry to see Richard to go, but will continue to listen.
- Frank, K4FMH, would like to see more technical content in future episodes.
- W. Lynn writes to say that the Belton HamExpo will be April 20, 2013 in Belton, TX.
- Gary, KE2YK, will miss Richard, too. He also appreciates the mention of Linux Mint 14 as it reminded him to give it a try.
- Pete, VE2XPL and the host of the wAVEgUIDES podcast, sends his congratulations on 100 episodes and best wishes for Richard.
- Gary, KE2YK, also sent comments about episode 101, including a link to his review of the Raspberry Pi.
- Brian, WB4ES, sends his thanks for Richard’s introduction to JT-75 screencast. (Available to subscribers.)
- There are more comments on LHS Facebook Page.
Contact Info:
- Contact Russ at [email protected] or [email protected].
- Listen to the live stream every other Tuesday at 8:00pm Central time. Check the LHS web site for dates.
- Leave us a voice mail at 1-909-LHS-SHOW (1-909-547-7469), or record an introduction to the podcast.
- Sign up for the LHS mailing list.
- LHS merchandise is available at the Merch link on Web site. Check out the Badgerwear or buy one of the other LHS-branded items at PrintFection.com/lhs or Cafe Press. Thanks!
- Thanks to Dave from Gamma Leonis for the theme music.
Music:
- “Insanity” by Mad Mav from the album Black Sheep, courtesy of Jamendo.
- “Strike the End” by Convergence from the album Points of View, courtesy of Jamendo.
LHS Episode #102: Run, It’s George Lucas!
Here we are, two episodes past the Richardocalypse and the calendar hasn’t run out yet! This time around, I’d like to thank Rob from MintCast for once again stepping in to be a co-host on the show, filling in the left big toe of the shoes once worn by The Richard himself. Since I barely fill a pinky toe, myself, that’s really saying something. In this episode we go a little ham nutty with Linux thrown in. Topics range from slow-scan television to licensing requirements to Rob asking, “What do I need another damned hobby for??” That question and many others answered in this fabulous installment of Linux in the Ham Shack.
73 de Russ, K5TUX
SSTV on an iOS Device
From the “Oh, How Cool is That?!” department, is a video to round out a week’s worth of Ham Radio videos, showing an iOS device, (iPhone,iPod Touch,iPad) decoding an SSTV signal. I have seen a bunch of Ham Radio apps on the iTunes App store, but I seemed to miss this one. According to the link in the video’s description, the SSTV Decoder app is made by Black Cat Systems, who also make a few other Ham Radio programs for Macs. The webpage says “.. Just connect it to an HF radio (or even set it next to the radio’s speaker), tune in an SSTV frequency, and watch the pictures.” From the video I didn’t see a directly connected cable from the iPod Touch, so I’m guessing that they are using a 4th Generation iPod Touch with a built in microphone and have it sitting close to the radio to hear the SSTV tones. Still, it looks like it received a nice picture. But they could also have been replaying pre-recorded picture on the device too. Either way, it’s cool!
73.
Rich also writes a Tech blog and posts stories every Tuesday and Thursday on Q103, Albany’s #1 Rock Station website, as well as Amateur Radio stories every Monday thru Friday on AmiZed Studios and hosts a podcast called The Kim & Rich Show with his fiance’ Kim Dunne.
ARISSat-1 One Month in Service
This one is going to be a little short, but here is some highlights of the ARISSat-1 on the event of it’s 1 month of service, and the 1 month of me trying to still receive it. While I am not bitter, I do cry myself to sleep sometimes at night, knowing I may never get to hear it. And if you believed that last sentence, I have some bridges in New York City I would like to offer you a great deal on.
So, here are some of the articles I have posted about ARISSat-1:
Watch ARISSat-1 Deploy on NASA TV [VIDEO]
Track and Watch ARISSat-1 on The Go!
ARISSat-1 the Easy Way [VIDEO]
Also, Douglas, KA2UPW/5 has reported that over 3000 frames of telemetry data has been sent in from the satelitte in the last 2 days. So things are still looking good. If you have any images from the SSTV on the satellite, please share them. I would love to see them.
Now, I haven’t really added much more on the ARISSat-1 because I didn’t want to get too bogged down with it. There are a ton of other stores I wanted to touch on as well. And I will be as we move forward. One of which is an Apple Cider Mobile as Autumn approaches and Apple Cider becomes the new beer for the evenings. Along with cider donuts and cheese curds and all the other goodies you can get at those small stores at family apple orchards here in Upstate NY. All this makes for a fun night at the radio on my favorite 2 meter repeater.
73.
Rich also writes a Tech blog and posts stories every Tuesday and Thursday on Q103, The Rock of Albany’s website, as well as Amateur Radio stories every Monday thru Friday on AmiZed Studios and hosts a podcast called The Kim & Rich Show with his fiance’ Kim Dunne.
Watch ARISSat-1 Deploy on NASA TV [VIDEO]
It’s the big news of the week for Amateur Radio. ARISSat-1 will be deployed today from the International Space Station thanks to 2 Russian Cosmonauts. The satellite will have 4 Slow Scan TV cameras as well as a CW and BPSK beacon. According to what I have read you’ll be able to pick it up with just a simple hand held and a quarter wave whip antenna. I plan on testing that statement out myself.It’ll also have on board, a cross-band linear transponder for SSB/CW work. A little something for everyone. I’m thinking the SSTV is going to be what I am shooting for. AMSAT-NA has a special page setup with more information on how to receive signals from the satellite. Below is the live feed from NASA-TV. The Sat is being deployed at 14:00 UTC.
73.
Rich also writes a Tech blog and posts stories every Tuesday and Thursday on Q103, The Rock of Albany’s website, as well as Amateur Radio stories every Monday thru Friday here on AmiZed Studios.