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V or H

Posted: Mon Mar 19, 2018 3:10 pm
by G1BVI
The launch of Es hail sat is probably soon, so I am getting my receive station set up.
80cm dish, one of Darkos modified dual output LNBs and a MiniTiouner.

I was wondering what is the proposal for polarisation.
The Minitiouner puts the supply volts on the F connector pin and most amateurs use 13.8V power supplies.
This means that it will be in vertical mode.
From memory a LNB requires 15.5 to 18V for Horizontal polarization.

Not sure if I want to push my supply up that high for fear of damaging the mini tiouner and my other kit.

If not I assume we will have to remove the link on Minitiouner that puts a voltage on feed and use a Bias T and feed a suitable voltage.

Does this mean that the amateur standard is going to be transmitting vertically polarized?
My LNB has a LO of 9.3887 Ghz not 9.75 Ghz so what frequency should I set my Minitiouner for Es Hailsat?

If I set up dish with a standard LNB to align it, is there a scan function in minitiouner software to search for a signal?

Hope someone can guide me.

Thanks in advance

73

Nick

Re: V or H

Posted: Mon Mar 19, 2018 3:15 pm
by g0mjw
The minitouner V2 was designed with a DC-DC converter to allow this. However, if you are concerned there is nothing to stop you feeding 18V, via an appropriate fuse, into the side of the link that goes to the tuner bias T. You could also adopt the radical solution of rotating the LNB by 90 degrees.

Mike

Re: V or H

Posted: Mon Mar 19, 2018 3:41 pm
by G1BVI
Thanks Mike.
Looking at the schematic the input feed goes to the DC to DC converter to limit the voltage to 3.8V thus protecting the minitiouner but not other kit hi hi.

I think I will make another supply that I can switch between the two voltages to feed the tuner.

The other question I forgot to ask is how to switch between LNB outputs.
Can anyone recommend a suitable 22 khz tone generator?

73
Nick

Re: V or H

Posted: Mon Mar 19, 2018 4:04 pm
by g0mjw
Another option is to use a spare satellite receiver with a loop through capability. These have all the appropriate driving circuitry.

If not, Ron Mount developed a DiSEqC board and it was published in CQ-TV250. See here viewtopic.php?f=10&t=4415&hilit=g7doe some small changes to the code will do what you want.

Mike

Re: V or H

Posted: Mon Mar 19, 2018 8:48 pm
by G8GKQ
Nick

There's a good authoritative summary of Es'hail 2 to download here: https://forum.nasaspaceflight.com/index ... 139;sess=0. The frequencies and polarities are on slide 14.

The DATV downlink is from 10481 - 10489, so with your LO of 9388.7. you'll need to tune between 1092.3 and 1100.3 MHz. There won't be a single ATV frequency in there, probably initially a beacon transmission with continuous video at one end of the band, with the rest of the bandwidth available for normal DATV or RB-TV transmissions.

Some of the BATC members are involved in the development of a web-based spectrum monitor to help with frequency coordination and signal identification.

Dave, G8GKQ

Re: V or H

Posted: Tue Mar 20, 2018 9:38 am
by G1BVI
I will take a look at the DISEqc article.

Thanks for the link too Dave very informative presentation.
I only have the Minitiouner for receiving.

Id it possible to set a scan up in the software.

The spectrum monitor sounds an interesting new development.

Thanks again to all

73

Nick

Re: V or H

Posted: Tue Mar 20, 2018 6:58 pm
by G1BVI
I have just upgraded the shack PC from a lap top to a Windows 10 desk top with decent monitors. and re installed MiniTioune.

I then noticed that there is a 22kHz radio button in the tuner section .
I had missed that before.

I have gone through the ini file changing my call sign etc and the video mode is left at the default of 3.

When I open mini tioune however it is not full screen.
How can I get it to fill my screen?
The square in the top right is greyed out.

On the desktop short cut properties is set to normal qindow.
If you set it to maximum you get grey fill in to the right and bottom of screen.

If you try and drag the right side and bottom out you get a grey fill in.

How do you get the GUI to expand to the full screen size ?

Thanks in advance

73

Nick

Re: V or H

Posted: Wed Mar 21, 2018 1:08 pm
by G4EWJ
By pressing the ESC key or clicking the MiniTioune video display window, you can change the size of the video display window and that gives some full screen video display window options. I don't think that there's any way of expanding the other options to full screen.

Brian