SatSig topic:

How to adjust LNB frequency to 10 GHz

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Mar 8^th, 2007 at 4:41am

I pointed the dish to express 4A ,I entered all required Data correctly but error value still over range.

The LNB Model is NJR2784HH ,I used it for 2 way.

when i want to point my dish to any satellite , I use tv reciver and change LNB from UNV to 10 GHZ then enter channel freq and SR then get signal.
Now I want to adjust the LNB freq to 10 GHZ by linkstar modem commands .

please help me.

Jun 26^th, 2007 at 12:47pm

The -f parameter in the save bootparam command specifies your LNB freq. oscillator. You just have to enter there the teleport frequency-LO (in Hz).

Jun 26^th, 2007 at 7:23pm

The NJR2784H LNB has a fixed 10 GHz LO frequency.

A universal satellite TV LNB has 9.75/10.6 GHz LO frequency, switchable using a 22kHz tone.

If you have lined up the dish using a universal satellite TV LNB set to 9.75 GHz and a satellite TV receiver, then if you change to a NJR2784H 10 GHz LNB and linkstar modem the L band frequencies will all be 250 MHz lower.

Subtract the LNB LO frequency from the satellite downlink frequency to get the receive L band cable frequency.

The latest DVB-S2 linkstar modem spec says it is "universal LNB compatible" so I guess it has commandable LNB voltage or 22 kHz tone to switch the LNB frequency. Invacom do high quality universal VSAT LNBs with various switchable LO frequencies and either voltage or 22 kHz tone to control the frequency choice. I don't know the linkstar commands to use.

I am not aware that the older linkstars had this facility, instead you had to pre-buy the correct LNB, with either 9.75, 10, 10.6, 11.3 GHz LO frequency, according to where you wanted to use it.

I am pleased with the trend towards VSAT modems becoming compatible with universal LNBs. It will encourage the use this this new TRIA which comprises a switchable universal PLL LNB and a 3 watt Ku band BUC all in one neat small module.
wxw
Best regards, Eric.