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1  VSAT technology and installation / Hub and VSAT satellite equipment for sale and wanted / For sale: Parts for a motorised Hughes Direcway antenna.
 on: Apr 4th, 2020 at 6:45pm 
Started by Admin1 | Post by Admin1  
For sale: Parts for a motorised Hughes Direcway antenna.

The parts shown in the images below are to be sold as seen. There is no indoor antenna control unit or a Direcway / Hughesnet modem.  The seller is therefore unable to test and it is not known if the kit is in working order.

...
View of the motorised Direcway antenna.

...
Views of some electrical part with word "HALO" visible.

If you search the internet further you may hopefully find more details of the actual manufacturer of the control box and electronics. It seems me that the same indoor control unit and motor mechanism are being used by a number of resellers, each with their own ideas of antenna size, purpose (VSAR or satelite TV).

Hopefully these items will be valued by some enthusiast who can either buy the relevent indoor control box or otherwise develop such a controller. I speculate that it might provide the basis for some student engineering project!.

There are approximate similarities with advertised motorised antennas on the internet intended to be used on RVs, campervans and mobile homes.

See examples:

Altech-UEC-Halo-satellite-dish.html

ebay for sale: Halo-ST85-Automatic-Satellite-TV-Dish

The antenna positioning motors and mechanisms allow the dish to be repointed once the vehicle is parked up at a new location. With an additional controller, and modifications to the RF assembly to remove the transmitter and perhaps with a new or repurposed LNB the equipment might be made to receive satellite TV (receive only).

I should emphasise that the equipment parts are untested and may not work. Significant skill and new parts will be needed to make use of them.

If you are interested in buying these parts please email me eric@satsig.net quoting reference "27/03/2020, 18:15" and I will forward your email to the seller.

Best regards, Eric (on behalf of the seller)

2  VSAT technology and installation / Hub and VSAT satellite equipment for sale and wanted / Wanted: New or Used iDirect 5100 routers
 on: Mar 30th, 2020 at 9:14pm 
Started by Admin1 | Post by Admin1  
Wanted: Quantity = 20.    New or Used iDirect 5100 routers

If you can help please email:   neil@satcomsolutions.org

Best regards, Eric

3  Anything else / General and other topics / OneWeb files for Chapter 11 bankruptcy.
 on: Mar 30th, 2020 at 5:15pm 
Started by Admin1 | Post by Admin1  
OneWeb files for Chapter 11 bankruptcy.

OneWeb has so far launched 74 satellites for its low erath orbit (LEO) constellation, intended to work with 44 earth station teleport hubs, about half of which are either completed or in development. Work has also been done on customer terminals. Successful demonstration tests have shown broadband speeds in excess of 400 Mbps and latency of 32 ms.

The Company and certain of its controlled affiliates have voluntarily filed for relief under Chapter 11 of the Bankruptcy Code in the U.S. Bankruptcy Court for the Southern District of New York.

The Company intends to use these proceedings to pursue a sale of its business in order to maximize the value of the company.

For more information read the full press release here:

OneWeb files files for Chapter 11 bankruptcy.

Wishing them well, both business wise and heath wise.

Best regards, Eric.

4  VSAT technology and installation / iDirect Forum: hubs and terminals / Re: TAC login
 on: Mar 28th, 2020 at 11:25am 
Started by ydh - Ex Member | Post by Admin1  
Determining the correct output power setting from the modem that will cause your BUC to saturate is not easy.

The purpose is to define the maximum value for operational use, that will never be exceeded. The value varies accoring to your cable length.

You will normally set the operational power somewhat backed off from saturation. The exact value will be told to you by the satellite network operations centre (NOC) during the carrier line up.

Typically the process will involve you chnaging to a specific frequncy and using unmodulated CW carrier.

Your modem output power level will be reduced to minimum and then increased in steps of 1 or more dB, while the carrier level is measured at the NOC. Initially the measured level will go up 1 dB per 1 dB.  This is called the linear operating range.  As the BUC input power reaches a high value the measured signal will start to go up by smaller increments.  If the NOC plots a graph of modem output versus measured satellite carrier the result will look something like this:

...

The key value is the -1 dB gain compression point, where the curved line falls 1 dB below an extension of the straight linear operation line.

If you are using a Comtech 570L then you may record the DC current and volts used by the BUC. Write these figures down as it becomes you only local measure of what the BUC is doing. (This assumes you are a VSAT and don't have a waveguide power tap on the BUC output and a Agilent power meter or similar. Teleports have output waveguide power monitoring and microwave spectrum analysers to measure any intermodulation when multiple carriers are used.)

BUC manufacturers normally tell you the guaranteed output power (watts) at the -1 dB compression point. The graph above shows a BUC specified at +3 dBW output but actually capable of +4 dBW, at it actual -1dB gain compression point.

I would still recommend using it only at +3dBW as this will give you a clean undistored signal and not exceed th manufacturers rating.

If you go above the -1 dB gain compression point the signal level will increase slightly as the BUC saturates, but the result will be interference to adjcent carriers and distortion of the wanted signal modulation and thus  reduction in quality (increased error rate). Further increase in input power to the BUC may permanently damage the BUC, so be careful adjusting the modem output power. It is important to avoid interference to adjacent carriers.

If you are desiging a link budget it is prudent to use generously rated BUCs so that in normal service the power out is perhaps 6 dB below the -1dB compression point. This gives a good margin for uplink power control to mitigate rain fades. Also, as time goes by the satellite operator may ask you to increase power.

Best regards, Eric.

5  VSAT technology and installation / iDirect Forum: hubs and terminals / Re: Link budget calculations
 on: Mar 27th, 2020 at 9:38pm 
Started by ydh - Ex Member | Post by Hamod  
Thank you Eric for your message.

I found out that increasing of the power in a comtech modem for example (cdm 570l) is not a power settings but a reduction in attenuation. How do i know i have saturated my BUC?

6  Service Providers / Satellite Internet - Americas / Viasat Vs Hughesnet
 on: Mar 25th, 2020 at 10:01pm 
Started by fokes306 | Post by fokes306  
I wrote a comprehensive overview of Hughesnet Satellite internet vs Viasat internet.  This should give anyone here a good idea of the good the bad and the ugly of these products.  https://www.konecteaze.com/viasat-vs-hughesnet-which-is-best-for-your-internet-n... curious to hear the forums thoughts.

7  Service Providers / Exede satellite broadband forum (was Wildblue) / Re: Wildblue warning!
 on: Mar 25th, 2020 at 10:00pm 
Started by jstew - Ex Member | Post by fokes306  
Honestly, I don't think its a scam.  WildBlue which is now Viasat, strives to provide good service but sometimes things fall through the cracks.  I don't think anyone was purposely trying to scam you.

8  VSAT technology and installation / iDirect Forum: hubs and terminals / Link budget calculations
 on: Mar 21st, 2020 at 10:10am 
Started by ydh - Ex Member | Post by Admin1  
I suggest you play around with this link budget calculator:

http://www.satsig.net/linkbugt.htm

Try various dish sizes and transmitter powers and different satellite parameters.   Satellites with small spot beams will have high G/T on the uplink.

http://www.satsig.net/link-budgets/

This index page gives many link budget examples and explanations of the various terms used.

Best regards, Eric

9  VSAT technology and installation / iDirect Forum: hubs and terminals / Re: TAC login
 on: Mar 20th, 2020 at 10:28pm 
Started by ydh - Ex Member | Post by Hamod  
Hi everyone,
I'm new in VSAT technology but i need your help on how to design a transmission plan/Link budget on VSAT link on a c-band and ku-band. This will go a long way in helping my career. I anticipate your response

10  VSAT technology and installation / iDirect Forum: hubs and terminals / MPLS QoS over L2oV
 on: Mar 18th, 2020 at 3:11pm 
Started by Kibbbaa | Post by Kibbbaa  
Hello,

I am using the L2oV feature of the iDirect x7 modem to extend MPLS over VSAT.  I am running into issues with the QoS b/c the iDirect system does not recognize the EXP bit.  Has anyone else tried to get iDirect to prioritize packets based on EXP bit and how did you overcome this obstacle?