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Ku-Band VSAT Photos (click here)
Photo's from a project I was responsible for in 2010 installing telephone and internet connectivity for several UAV bases in Afghanistan consisting of eight Patriot 1.2 meter Ku-band VSAT TDMA systems using iDirect modems.

iDirect 5150 Satellite Modem.
LNB: 1209HCF 10 GHz LO. 10.95-11.7 GHz.

A Very Small Aperture Terminal (VSAT), is a two-way satellite ground station with a dish antenna that is smaller than 3 meters. Most VSAT antennas range from 75 cm to 1.2 m. Data rates typically range from 56 Kbit/s up to 4 Mbit/s.

More about VSAT systems here:


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1.2 Meter VSAT Antenna with 8 watt BUC. Customer supplied flex waveguide. Edit

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1.2 Meter 8 Watt BUC Upgrade. Brackets required to hang the relatively heavy BUC compared to the previously used 3 Watt BUC.

Why the upgrade from a 3 to 8 watt capable block up converter?

When using the smaller 1.2 Meter diameter antenna the other end or gateway earth station can usually make up for our being at a weak spot by just transmitting more individual carrier power to us, but the small 1.2 M VSAT antenna we have at this location does not have enough gain to be able to transmit enough signal to the bird without a higher power BUC such as this 8 watt unit. When in a weak area of the satellites footprint, both ends must transmit more power, within limits of course, if too far out you can't make up for the loss.

There is another way of accomplishing the same thing, to have a bigger antenna on the ground which has higher receive and transmit gain, making a higher power amplifier unnecessary. If this location had a 1.8 meter dish we would not need more TX power.

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Antenna secured on 1 inch thick plywood on top of shipping container. Both straps and sand bags were used to hold the antenna in place against moving during high winds.

See anything wrong with this antenna? The folk out at this location put it together before I arrived and had something in the wrong place, see it? Well, two things were swapped to the wrong ports.

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Patriot 1.2 Meter Ku-Band Antenna on top of office built inside of a Conex shipping container. Edit

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Patriot 1.2 Meter Ku-Band Antenna. When seeking to find the bird or satellite I found the process to be much easier and go much quicker if I disconnected the azimuth worm screw drive and turn the az of the dish by hand then once finding the bird put it back on. This way you only need to adjust the elevation jack screw and easily swing the dish left and right to find the bird. Edit

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iDirect 5150 Modem on top of UPS. The white box on the floor left of the modem is a 60 VDC power supply for the 8 watt BUC. The iDirect modem cannot supply enough power to drive the higher power BUC. Be careful not to mix up your two coaxial cables, if you send that 60 VDC up to the LNB it's probably going to fry. Also, don't mix up the in's and outs of that power supply coming from the iDirect modem or you may fry it too, if sending 60VDC into the TX output connector of the modem, voltage which should being going to the BUC, not to the modems TX output. I believe the folk who received this kit tried to put it on the air without me and did exactly that, after that the L-Band RF output of the iDirect modems TX output was more than 30 dB low, too low to drive the BUC. Edit

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Programming instructions for the iDirect 5000 series satellite modem using iSite software. Note: Best to use Windows XP with service pack 3 installed or the iSite software might not work.

You also need a serial cable to communicate between a laptop and the console port on the satellite modem to determine the modems IP address which will be used with iSite to program the unit. For laptops without a serial port use a USB to serial adapter with DB9 connector on the end of the cable, then attach a Cisco serial port cable to the DB9 and jack the RJ-45 connector on the end of that cable into the RJ-45 receptacle console port on the back of the satellite modem.

If you already know the IP address of the iDirect modem you don't need to do this and can use a Cat. 5 cable and your computers LAN port between any of the iDirect modems 8 LAN ports on the rear of the unit to communicate with the modem using iSite. Due to auto sensing either a strait through or null cable should wo...

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More detailed programming instructions for the iDirect 5000 series satellite modem using iSite software. I used iSite 7.07 to program the modems for this customer. It is a rather large file you will need to download. I cannot include it here, zip files for such programs are not allowed on this web site.

What do you need this software for? If the satellite provider has not pre-programmed your iDirect satellite modem with the proper configuration such as frequency and other parameters, you will need to use this program to load that file. This file can be emailed to you and is very small but requires this software to load it. Also, this software will allow you to tell the modem the test frequency to transmit on so you can set your cross-polarity isolation with the satellite internet service provider, when using a linear or polarized feed which is common. Setting the cross pole requires the feed to be slowly turned as someone watches your carrier at the gateway earth station.

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Example of the programming configuration for a iDirect modem. This information can be read using iSite software. Edit

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Patriot 1.2 Meter VSAT Antenna. Edit

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