SATELLITE MODE

r2dze
Posts: 8
Joined: Tue Sep 14, 2021 2:20 pm

Re: SATELLITE MODE

Post by r2dze » Tue Sep 14, 2021 3:11 pm

Really like the new sat mode, so nice and simple, no need to have a PC around to keep the frequency. Here is my setup and gratitude to the team making it possible! - https://youtu.be/XPU-AwkOvCA?t=515


youtu.be/XPU-AwkOvCA


Thank you!

What might be an extra wish is to be able to somehow get az/el data out of the radio via programming port in order to control antenna rotator as well. Though not sure if it is possible to push data to the port in easily accessible serial mode.

VK3KYY
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Re: SATELLITE MODE

Post by VK3KYY » Tue Sep 14, 2021 9:46 pm

r2dze wrote:
Tue Sep 14, 2021 3:11 pm
Really like the new sat mode, so nice and simple, no need to have a PC around to keep the frequency. Here is my setup and gratitude to the team making it possible! - https://youtu.be/XPU-AwkOvCA?t=515


Thank you!

What might be an extra wish is to be able to somehow get az/el data out of the radio via programming port in order to control antenna rotator as well. Though not sure if it is possible to push data to the port in easily accessible serial mode.
Yes. It would be easily possible to send the Az / El to the USB.

The main problem is that you would need to make a special USB / Microphone cable, because the normal speaker mic cables don't have the USB connections :-(

So you would need to make your own plug from a 2.5 and 3.5mm jacks

I know someone made a splitter cable buy buying some 3.5mm and 2.5mm extension cables and cut them.

3.5mm spliter cables are common for audio but 2.5mm splitters are not easy to buy :-(

If you have a motorised system, and want to build a cable, let me know and I could modify the firmware for you to send the Az / El via USB serial, but you would also need to have some PC or RPi program to use that data

r2dze
Posts: 8
Joined: Tue Sep 14, 2021 2:20 pm

Re: SATELLITE MODE

Post by r2dze » Wed Sep 15, 2021 10:35 am

Hello, Roger. Understood, thanks!

I have no problems with cabling, already made several programming ones from 2.5+3.5mm jacks to plug to raspberry pies for the hotspot mode.

As for rotator i have built one based on designs (https://sarcnet.org/rotator-mk1.html) of Julie VK3FOWL and Joe VK3YSP last year, here it is up and running

youtu.be/hkSU5nQm_dI

Right now it is arduino inside controlling motors and getting elevation and azimuth data fed from PC GPredict software.

Having el/az data from DM-1801 via USB/Serial would potentially allow to eliminate the PC part completely! Though not sure arduino would suffice to connect to USB protocol and i probably would need at least raspberry pi in between. But need to investigate it still though on whether it is possible to easily get USB data to arduino directly...

VK3KYY
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Location: Melbourne, Australia
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Re: SATELLITE MODE

Post by VK3KYY » Wed Sep 15, 2021 11:20 am

r2dze wrote:
Wed Sep 15, 2021 10:35 am
Hello, Roger. Understood, thanks!

I have no problems with cabling, already made several programming ones from 2.5+3.5mm jacks to plug to raspberry pies for the hotspot mode.

As for rotator i have built one based on designs (https://sarcnet.org/rotator-mk1.html) of Julie VK3FOWL and Joe VK3YSP last year, here it is up and running

youtu.be/hkSU5nQm_dI

Right now it is arduino inside controlling motors and getting elevation and azimuth data fed from PC GPredict software.

Having el/az data from DM-1801 via USB/Serial would potentially allow to eliminate the PC part completely! Though not sure arduino would suffice to connect to USB protocol and i probably would need at least raspberry pi in between. But need to investigate it still though on whether it is possible to easily get USB data to arduino directly...
You would need something like a Raspberry PI, becuase the OpenGD77 firmware can only operate as a USB client, and the Arduino also can only operate as a USB client.
The RPi can operate as a USB host, and the GD77 will appear as a normal COM device.

Technically you need to configure the "udev" rules for the USB device but its not complex.

However I don't know how you interface to the Arduino from the PC, perhaps it sends data to the Arduino as a serial device.


BTW.

I think your "rotator" is not able to control polarisation. I noticed when manually pointing my beam, that often the polarisation needs to be at 45 deg etc.
I suppose a cross yagi or something with circular polarisation would be better.

r2dze
Posts: 8
Joined: Tue Sep 14, 2021 2:20 pm

Re: SATELLITE MODE

Post by r2dze » Wed Sep 15, 2021 4:09 pm

VK3KYY wrote:
Wed Sep 15, 2021 11:20 am
I think your "rotator" is not able to control polarisation. I noticed when manually pointing my beam, that often the polarisation needs to be at 45 deg etc.
I suppose a cross yagi or something with circular polarisation would be better.
True, no polarization control in rotator and you are right, cross-yagi is what i have long plans to build or acquire as well as sometimes polarization mismatch between antenna and sat signal makes it inaudible.

VK3KYY
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Location: Melbourne, Australia
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Re: SATELLITE MODE

Post by VK3KYY » Wed Sep 15, 2021 9:00 pm

Perhaps we should add an option called Data, which when enabled sends

AZ:DDD
EZ:DD

r2dze
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Joined: Tue Sep 14, 2021 2:20 pm

Re: SATELLITE MODE

Post by r2dze » Thu Sep 16, 2021 7:24 am

VK3KYY wrote:
Wed Sep 15, 2021 9:00 pm
Perhaps we should add an option called Data, which when enabled sends

AZ:DDD
EZ:DD
Would be great to start testing connectivity with rotator!

Format supported by hamlib / rotator control library (http://hamlib.sourceforge.net/html/rotctl.1.html) is the following:
'Azimuth' and 'Elevation' are floating point values.
Azimuth can be -180 to 540 depending on the rotator to allow for rotators facing south and the capabilities of the rotator.
Elevation can be -20 to 210 depending on the rotator.
For example:
P 163.0 41.0
What i also realized, having data cable plugged in, audio feed will be muted. So either custom cable to have both external speaker and data connectivity would be needed, or the one connected to rotator to be used for TX, and another radio for RX.

VK3KYY
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Re: SATELLITE MODE

Post by VK3KYY » Thu Sep 16, 2021 7:33 am

Yes.

Plugging in a cable mutes the audio. So you'd need to use an external speaker / mic, and a spitter cable.

VK3KYY
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Re: SATELLITE MODE

Post by VK3KYY » Tue Sep 21, 2021 1:08 am

r2dze wrote:
Tue Sep 14, 2021 3:11 pm
Really like the new sat mode, so nice and simple, no need to have a PC around to keep the frequency. Here is my setup and gratitude to the team making it possible! - https://youtu.be/XPU-AwkOvCA?t=515


youtu.be/XPU-AwkOvCA


Thank you!

What might be an extra wish is to be able to somehow get az/el data out of the radio via programming port in order to control antenna rotator as well. Though not sure if it is possible to push data to the port in easily accessible serial mode.

Did you try without the duplexer

If you have separte feeds to the 2 driven elements of the 2m and 70cm yagi's, then you may not need the duplexer, and it may improve the performance of the antenna if you don't have the duplexer.

r2dze
Posts: 8
Joined: Tue Sep 14, 2021 2:20 pm

Re: SATELLITE MODE

Post by r2dze » Tue Sep 21, 2021 8:37 am

VK3KYY wrote:
Tue Sep 21, 2021 1:08 am

Did you try without the duplexer

If you have separte feeds to the 2 driven elements of the 2m and 70cm yagi's, then you may not need the duplexer, and it may improve the performance of the antenna if you don't have the duplexer.
My antenna is single cable fed by design, so no way to work in duplex two station cross-band without duplexer. However I am pretty sure when one station would TX full power and another is RX at different band using the same antenna setup separately fed, the receiving one would be almost completely blocked by the strong signal of another, even though they are on different bands. Just tried it with two stations in proximity - and yes, receiving one getting signal readings and noise becomes lower, when another is TX on a different band. So that having duplexer which is isolating 2m and 70cm bands by additional 60+db is a benefit. In band through losses of the duplexer are quite low.

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