Which C-Band LNB is better to receive weak signals?

Do you know how to select good CBand LNB for weak satellite signals? So today I decided to check all C Band LNB’s technical specifications. I am writing these details in short so that your time will not be wasted.

Best C Band LNB –

If you are thinking to buy CB LNB and are confused about which one is good for you then you should check some important information about CBand LNBs technical specifications:

1. Input Frequency:

3.4 ~ 4.2

This frequency C-band lower band is used by traditional or old satellites. So please check your satellite TP frequency if the TP frequency starts from 3400+ then you should buy a lower band supported LNBF, This C-Band LNBF supports frequencies of 3400 to 4200.

3.7 ~ 4.2

It is a normal C-Band Input frequency used by the latest satellites launched after 2012-2015.  If your satellite broadcasts C-Band TV channels from 3700 to 4200 frequency then you should buy this LNB. It is also called filter LNB. Because it will save terrestrial, Wimax, or mobile tower interface.

4.2GHz ~ 4.5GHz

It is a very special LNBF, it is called extended upper band C-Band frequency. currently, the Bangabandhu satellite is using this bandwidth. TP list starts from 4200 to 4500 MHz. To receive this type of TV channel, you should buy Extended Filter LNBF.

Conclusion for this part: –

You should buy C-Band LNB with 3.7 ~ 4.2 Input Frequency but keep in mind that you cannot scan transponders with frequencies 3400 to 3699. (If any are available like in Asiasat 7)

2. Noise Figure / Factor / Temperature:

Yes, everyone wants to know which LNB is better with a low noise figure or high noise figure. The LNB quality is measured in units called Noise Temperature, Noise Figure, or Noise Factor. I think both the Noise Figure and Noise Factor may be converted into Noise Temperature. So the lower Noise Temperature is always better but it totally depends on your satellite gain. See how the same LNB can be good or bad –

For Low Gain Satellite Signals:

• If C-Band LNB Noise Figure is below 13K = Very good LNB – You will get very good signals for all TP
• If C-Band LNB Noise Figure is below 15K = Good LNB – You will get good signals for all TP
• If C-Band LNB Noise Figure is below 17K = Normal LNB – You will get normal signals and you may miss some TPs.
• If C-Band LNB Noise Figure is above 17K = Worst LNB – You will get low signals for a few TPs or some TPs you may not find.

For High Gain Satellite Signals:

• If C-Band LNB Noise Figure is below 13K = Worst LNB – You will get very high signals, Your STB may skip scanning All TP.
• If C-Band LNB Noise Figure is below 15K = Normal LNB – You will get high signals, Your STB may skip scanning Some TP. Your picture may freeze every few minutes.
• If C-Band LNB Noise Figure is below 17K = Good LNB – It depends on the satellite gain level. You may receive good signals on some TPs.
• If C-Band LNB Noise Figure is above 17K = Very Good LNB – It depends on the satellite gain level. You will receive good signals in all TPs.

Conclusion for this part:

So always you should buy low-noise C-Band LNB because in India most of the satellite has coverage of normal or weak gain (in dB) if you are from another country then check satellite gain in your area.

3. 13/18V Voltage Switching or Dual Polarity:

First, understand the dual polarity or voltage switch function in LNBs. here

• If your satellite receiver is transferring 13-14 Volt power to LNB then you will get Vertical signals.
• If your satellite receiver is transferring 17-18 Volt power to LNB then you will get Horizontal signals.

If your LNB automatically manages this voltage switching function according to set-top box power then your LNB has a dual polarity feature. You will receive Horizontal and vertical transponders in a single LNB. Conclusion for this part: For weak C-Band satellite signals, you should always use two signal polarity LNBs (means C-Band LNB without voltage switching function) because at the time of installation in dual polarity LNB when you set signals for vertical then you may lose some horizontal transponders & if you set horizontal transponders then you may lose signals for vertical transponders. But you can set separate signal polarity LNBs as needed. Or if the satellite has good satellite signals then you go with dual polarity LNB. You can find more topics related to LNBF to install the free-to-air system.