DiSEqC? 1.2

Has anyone worked with DiSEqC? 1.2 or other versions that communica te with a positioner for a kU band dish? Commercial units are typically $400 and up. I've found a few old references to a DIY controller using a PIC, but no code or much else. A Horizon to Ho rizon mount isn't difficult to build, and a gear drive with a stepper would be fairly simple as well. I want to try FTA satellite TV, without spending $1000.

Reply to
Michael Terrell
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you can turn the dish with your hand.

Reply to
Johann Klammer

nicate with a positioner for a kU band dish?

nces to a DIY controller using a PIC, but no code or much else. A Horizon t o Horizon mount isn't difficult to build, and a gear drive with a stepper w ould be fairly simple as well. I want to try FTA satellite TV, without spen ding $1000.

Not when it has to be over 15 feet in the air, to clear a tree. I'm disable d and I have trouble walking. I'm not about to drag out a ladder and climb it every time I want to change channels. The receiver can store the positio ns, along with the channels so you just use the remote to select the channe l.

Reply to
Michael Terrell

No idea about DiSEqC, but...

I've been thinking about building a home-brew alt-az rotator for my 1.5m galvanised steel dish. The trouble is to make the mechanism strong and stable enough to withstand wind gusts.

My thoughts have run along the idea of using two lazy-susan bearings mounted on a round pole, say 50-100cm apart in height, with timber verticals joining them. A windscreen-wiper motor below the bottom one can deal with azimuth, using a bicycle chain drive for example.

Then the dish itself is mounted near the top on a see-saw pivot with a counter-weight, and using a linear actuator that forms a triangle from a bottom pivot attached near the bottom lazy susan. That would deal with altitude.

It shouldn't require much or any metal fabrication to make this reasonably strong and durable. It might be interesting keeping the encoders dry though.

Let me know if you do build something, Michael.

Clifford Heath

Reply to
Clifford Heath

Nope. All the DBS stuff I installed or repaired used a fixed Ku or Ka band dish, and multiple LNB's to switch between satellites. The only motors I've had to deal with were in ancient C-band dishes and fine alignment large (12 meter) dishes that had to deal with separating multiple satellites in a single orbital slot. If there was any DiSeq technology involved, it was well hidden inside the controllers and actuators.

You mean an equatorial mount? They might be easy to build, but they are a nightmare to align properly. The satellites are spaced 2 degrees apart with an accuracy of 0.1 degrees. To insure that you don't get interference from the satellites in an adjacent slot, you'll need about +/-0.6 degree horizontal positioning accuracy. That's not easy to do with either an "arm-strong" rotator, or an electromechanical equivalent. The typical home C-band dish is basically an equatorial mount driven by a linear actuator. That's probably what you will end up using.

How many of these birds can you see?

Incidentally, when I was involved in moving these dishes around the property: I had considerable difficulty just finding the right satellite, much less positioning the dish to the optimum location. Never mind the protocols or code. Worry about the mechanical problems first.

If you're going to do it with worm or spur gears, think about backlash problems. I suggest you start with a simple Ku band 0.6 meter dish and J-mount and use it to try an find a satellite. That should give you a clue as to how critical dish alignment can be. Incidentally, for Ku FTA, the minimum dish size is about 1.0 meters dia. DBS (DirecTV and Dish) dishes won't work.

I might have a present for you. I inherited several older FTH (Free To Air) receivers and pile of DISEq switches from a friend. The receivers have been modified to decrypt Dish DBS programming. I think that I can put the original firmware back so you can use it for FTH. The catch is that I just closed down the office and everything is now scattered around the house and decks. I can't find anything. It will rain in about a month and everything on the decks will likely be soaked. Can you wait a month or more? Email in signature works. Remind me if I forget.

"Free to Air (FTA) Satellite Dish Setup"

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Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
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Reply to
Jeff Liebermann

Yes, I was thinking of the old portable RADAR systems that I serviced.

Those C band actuators are actually 24 volt trailer jacks. /they use an int ernal leadscrew to adjust the length of the arm. I've rebuilt many of them, and even straightened one that was bend by high winds.

They recommend a 30" minimum dish, but I should have one of those old dishe s from the Radio Shack systems that was 1.5 meters.. A rigid mount with the dish on a good set of bearing blocks will take care of play in the mount. Driving the leadscrew directly from a stepper , and a djustable end bearings will take care of the backlash. Unlike C-band, the e ntire arc is from 87 to 125 degrees, or 38 degrees from end to end. That si mplifies the design, compared to large and heavy C-band antennas.

SES 2 (87.0 W) Galaxy 28 (89.0 W) Galaxy 17 (91.0 W) Galaxy 3C (95.0 W) Galaxy 19 (97.0 W) Galaxy 16 (99.0 W) SES 3 (103.0 W) AMC 15 (105.0 W) Eutelsat113 (113.0 W) Eutelsat117 (116.8 W) Galaxy 18 (123.0 W) AMC 21 (125.0 W)

I had to replace a C-band dish that was ripped off the steel pipe, and the pipe was bent. I couldn't convince the owner that it had to be plumb, and i t was over 15% off after a storm. I ended up usingg a wide nylon towing st rap and his customize van to repeatedly jerk the top of the pipe until it w as usable.

Jeff, I installed and maintained multiple feed 5 Meter dishes for CATV Head ends. That included converting them from Cassegrain to prime focus. One was real fun. It was a SA dish, and conversion kit. The assembly drawings were wrong. the way it was drawn had the wrong focal length. I could sweep it 1

5 degrees and still have a poor signal through the entire range. Once we ha d the proper instructions, it worked like a charm. I installed an early Dis h system for my dad. It wasn't that hard to aim, and fine tune.

Thanks. I have a new in the box FTA receiver sitting here, along with a new LNB and mounting bracket so don't worry about it, for now. it is a GTMedia V8X HD Satellite Receiver.

I am using kA band for internet.It sucks, but it was the only service avail able after Spectrum refused to repair thir crap. It looks like Fiber is get ting closer to my place. I've seen the county's trucks installing plastic c onduit into new areas. I will gladly dump Hughesnet, if it becomes availabl e.

Reply to
Michael Terrell

cate with a positioner for a kU band dish?

es to a DIY controller using a PIC, but no code or much else. A Horizon to Horizon mount isn't difficult to build, and a gear drive with a stepper wou ld be fairly simple as well. I want to try FTA satellite TV, without spendi ng $1000.

It looks like I will have to design and build an analyzer for DiSEqC? ?? 1.2 too see the commands being sent to steer the motor, along with t he commands to store positions, and to recall them before I can build a wor king positioner.

Reply to
Michael Terrell

Eutelsat DiSEQc specs: See the bus specs and positioner app notes.

DiSEqC Protocol and Low-Noise Block Voltage

More:

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Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
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Reply to
Jeff Liebermann

te:

unicate with a positioner for a kU band dish?

ences to a DIY controller using a PIC, but no code or much else. A mount to allow tracking isn't difficult to build, and a gear drive with a stepper d riving a leadscrew would be fairly simple as well. I want to try FTA satell ite TV, without spending $1000.

?? 1.2 too see the commands being sent to steer the motor, along with t he commands to store positions, and to recall them before I can build a wor king positioner.

I found a zip file of all their documents after my last post

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I also found where someone used an Arduino to track the sun with DiSEqC ? 1.2 I will download their code to see if it has anything useful. It is the opposite of what I need, but it might lead to another project. Ma ybe a test set to test the switches and motors.

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Thanks, Jeff.

Reply to
Michael Terrell

Nice. I've wanted to build something like that for a solar power tracker using commonly available TVRO hardware. Yet another project.

I also found manual exert on controlling LNB's and Diseqc switches. Might be useful for something: "DiSEqC COMMANDS" It's part of the manual on their RangerNeo 2 spectrum analyzer. See the manual sections highlighted in bold text at: On the data sheet (Pg 22): it indicates that it has a built in Diseqc controller: DiSEqC commands Elementary DiSEqC commands are available from a drop-down list. They can be combined to form macros which can also be associated to a channel table. and: DiSEqC 2.x generator (DiSEqC 1.2 commands implemented) dCSS / SCD 2 (EN50607) and SATCR/SCD (EN50494)

Drivel: Looks like fire weather again on the left coast. It will be

104F today, low humidity, with possible high winds. If a fire starts today, it will likely spread quickly. Instead of playing on the computer, I'm going to load the car up with my survival kit and hope for the best. To be continued, I hope.
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Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
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Reply to
Jeff Liebermann

? 1.2 I will download their code to see if it has anything useful. It is the opposite of what I need, but it might lead to another project. Ma ybe a test set to test the switches and motors.

I'll check those out, and if I find anything else interesting, I'll sha re it here.

It was 60F here in N Central Florida yesterday morning. We finally had a break in the rain. I try not to go outside when it's wet, because I'f fall en several times.

I leave some supplies in my van, in case I have to bug out. Take care, a nd God Bless!

Reply to
Michael Terrell

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