For London UK
Sunday, 14 August 2016
Saturday, 13 August 2016
VP2ETE DX contact Saturday night
Saturday night using 100 Watts and an atas mobile auto-tuning antenna we worked :
SSTV mode PD120 transmissions on 145.800 MHz FM Aug 15-16
What is SSTV:
This is a way of transmitting pictures over the air, the picture is encoded into sound and sent via a transmitter. The picture is divided into lines and each line is sent one by one. You will see the picture build up infront of you.
The sound is received by another radio and a computer can decode the sound into the picture.
SSTV from the International space station is transmitted on 145.800 FM and is analogue.
This is good because if you get any interference you just miss a line or 2 of the picture (scratchy) not the whole thing.
The Event
Apparently the crew have been requested to reconfigure the equipment to PD120 according to Amsat UK site. The MAI-75 Experiment will transmit SSTV images using PD120 mode on 145.800 MHz FM over the course of a few orbits as the space station passes over Moscow. Operators in Europe and South America will have the best chances to receive images. Operators along the US East Coast may have one chance on August 16.
What can you do to take part?
Firstly how do you know where the space station is and when it will be near you?
Take a look at the NASA site: https://spotthestation.nasa.gov/sightings/ and enter your details.
You will get a list of approximate time the ISS will be in your location.
If you have a 144 scanner or radio tune into 145.800 open your squelch and listen for the fax like sounds.
A simple $40 beofeng Chinese radio is enough to get the signal.
Use your phone to record the signal.
Go outside, take your kids outside you don't need to be high up, just clear view of the sky...
Take pictures of your attempts and share them back to us..
Go outside, take your kids outside you don't need to be high up, just clear view of the sky...
Take pictures of your attempts and share them back to us..
If you don't have a radio you can use a web based radio (SDR) to pick up the signal: http://websdr.org.
For UK reception we tend to use: http://websdr.suws.org.uk/ select 146, tune to 145.800 FM
Use the record facility and download the file to your desktop.
Now my biggest suggestion here is to record the sound and decode it later on, trying to get the computer ready can be a pain on your first attempt.
You can of course use a more specialist cable connected between your radio and computer, but this article is aimed to help give everyone a chance in the simplest way possible.
If you are lucky enough to record a signal (please do share with us!) now you will need to decode it into a picture.
Android hone or tablet you can use: https://play.google.com/store/apps/details?id=xdsopl.robot36
iOS SSTV App https://itunes.apple.com/gb/app/sstv/id387910013
For your PC / windows you can use:Free MMSSTV Slow Scan TV software http://hamsoft.ca/pages/mmsstv.php
On the raspberry pi (1,2 and 3) you can install QSSTV: http://users.telenet.be/on4qz/qsstv/manual/installation.html
More on this later....
Once your decoding software is installed you just need to feed in your recorded SSTV sounds and within a few minutes you should have some pictures.
Here are a few images we got in the last year on these special events.
**Please do ask us question or for help... we are here for you!!**
Tuesday, 9 August 2016
Saturday, 6 August 2016
kg5cci: My Station - A Reference Post
The #1 question I get asked with regards to Ham Radio is "What kind of equipment do you use to operate on the Satellites?" - worded in about 47 different possibilities. I plan to make this post the one stop shop for my current AMSAT Station configuration, and I'll update it as needed if any life changing modifications are required.
So, how do I work Satellites? It comes to 4 things really.
I start with the Antenna because it paramount to successful operation on the birds. Yea Yea, you've heard it all before 'the antenna is the biggest part of your station' yada yada.. Well, I mean it. If your antenna system sucks, then don't even bother trying to get on the birds. Really. Seriously. Just go away. You'll end up transmitting in the blind and being deaf as a post and ruining the bird for everyone else. Whatever antenna you decide to use it needs to have some GAIN on it. I personally use two different varieties of Arrow Antennae (a small version and a big version.. more about that in a later post) for my operations and they work fantastically. You also may see me playing around 'cheap yagis' from time to time.. These are home-brewed gain antennae made out of plywood and welding rod. They also work pretty good. Any other type of gain antenna will work, but you're dealing with very weak signals, mostly < 1W, and so gain is absolutely required. Anyone who tells you it isn't, isn't a very successful operator.
Now we're getting into some places where there is room for interpretation. At it's heart, you need a rig (or rigs) capable of operating on the band and mode the Satellite is transmitting and receiving on. Simple enough right? At the moment my rig of choice for Satellite operation is my Icom 821h. It is a 2M/70cm dual VFO, full duplex, all mode rig. It has some nice features like VFO lock, RIT and some other things that make it nice for bird operation, plus it will do anywhere from 2W-30W on 70cm and 5W-40W on 2m - which is more than enough to get into the birds with a strong signal to overcome QRM when needed, but not enough I have to do a RF field study when running at modest levels (Or using AO-7(B) you QRO numpties). You will also see me using my 857d on occasion, and pairing it with a random HT. Sometimes if I'm doing just the FM birds, I'll be using my FT2900 in the Jeep as one side of the equation. Sometimes you'll see me using my FunCube Dongle Pro+ to receive SDR style. There's really a lot of choices here. Some work better than others, but you can make a whole lot of things work if you try.
Lots of different options here - I'll just go over a few that make my life easier. First - a headset. I use a Heil Pro Micro. When one hand is holding your antenna, and the other is trying to adjust the dial and write stuff down, having a headset is practically a necessity. Also in this picture, you'll see a battery. This is a personal preference thing, and you can read more about them in my Battery Powered blog entry, but I like the LiFePo4 battery packs for normal operation.
You'll also see in this picture a few more extras. There's Heil Audio footswitch that is used as my PTT button. See above necessity to have 4 hands to see why this is nice. I've also got a little cheap foldable table I bought at Home Depot to put everything on when I'm out in the field... It's the perfect height and perfect size. Finally I've got a big tub that all my gear goes into for easy packing. I'll almost always have pencil and paper.. sometimes I use a voice recorder, sometimes I'll have an external speaker on a tripod and a camera too.. it all just depends on what I'm trying to accomplish with that pass.
That's how I Satellite.
So, how do I work Satellites? It comes to 4 things really.
1: Antenna:
I start with the Antenna because it paramount to successful operation on the birds. Yea Yea, you've heard it all before 'the antenna is the biggest part of your station' yada yada.. Well, I mean it. If your antenna system sucks, then don't even bother trying to get on the birds. Really. Seriously. Just go away. You'll end up transmitting in the blind and being deaf as a post and ruining the bird for everyone else. Whatever antenna you decide to use it needs to have some GAIN on it. I personally use two different varieties of Arrow Antennae (a small version and a big version.. more about that in a later post) for my operations and they work fantastically. You also may see me playing around 'cheap yagis' from time to time.. These are home-brewed gain antennae made out of plywood and welding rod. They also work pretty good. Any other type of gain antenna will work, but you're dealing with very weak signals, mostly < 1W, and so gain is absolutely required. Anyone who tells you it isn't, isn't a very successful operator.
2. Good Coax:
OK, so that picture isn't actually the coax I use, but it's an example of a station owned by a guy who get's it, and thus, makes the point more dramatic. Use the best coax you can afford, and is practical for your station. In that picture, 7/8th hardline works... In my station, I use 2x 8' pieces of Times LMR-240. I almost emphasize coax as much as I emphasize using the proper antenna, because there's no way you can cause more damage to your ability to hear than using cheap lossy coax. Make sure to have the proper terminators on each end, that are high quality silver Amphenols, and make sure the coax is in good condition. Test it regularly to make sure it's as close to 0db loss as possible. I have gotten by with RG58 and RG8X in the past, but only on very short runs (like < 12") and usually only then for a novelty. When dealing with VHF/UHF frequencies, anything shy of LMR just doesn't cut it if you want to be a serious op.
3. Rig
Now we're getting into some places where there is room for interpretation. At it's heart, you need a rig (or rigs) capable of operating on the band and mode the Satellite is transmitting and receiving on. Simple enough right? At the moment my rig of choice for Satellite operation is my Icom 821h. It is a 2M/70cm dual VFO, full duplex, all mode rig. It has some nice features like VFO lock, RIT and some other things that make it nice for bird operation, plus it will do anywhere from 2W-30W on 70cm and 5W-40W on 2m - which is more than enough to get into the birds with a strong signal to overcome QRM when needed, but not enough I have to do a RF field study when running at modest levels (Or using AO-7(B) you QRO numpties). You will also see me using my 857d on occasion, and pairing it with a random HT. Sometimes if I'm doing just the FM birds, I'll be using my FT2900 in the Jeep as one side of the equation. Sometimes you'll see me using my FunCube Dongle Pro+ to receive SDR style. There's really a lot of choices here. Some work better than others, but you can make a whole lot of things work if you try.
4. Accessories
You'll also see in this picture a few more extras. There's Heil Audio footswitch that is used as my PTT button. See above necessity to have 4 hands to see why this is nice. I've also got a little cheap foldable table I bought at Home Depot to put everything on when I'm out in the field... It's the perfect height and perfect size. Finally I've got a big tub that all my gear goes into for easy packing. I'll almost always have pencil and paper.. sometimes I use a voice recorder, sometimes I'll have an external speaker on a tripod and a camera too.. it all just depends on what I'm trying to accomplish with that pass.
That's how I Satellite.
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