C-band : Higher conversion rate or lower Kelvin ?

karism

Morning guys!(Dont know if we have ladies here?)

I have searched,but get conflicting answers....

My Cband LNB is on the way out,it acts up every now and then.

Iam looking at a new Cband Lnb,just a single output one.

Which one the two is more important when looking for a new one ?(Or is it a combination?Or something completely different?)

1)The conversion Db of it?
2)The noise temp ?

I currently have : MTI AC13-2CV with the specs :

Frequency Range H: 950 - 1450MHz
V: 1500 - 2000MHz
Connector Type 75Ω Female Connector
VSWR 2.5:1 (max)

Local Oscillator
Frequency H: 5.150GHz
V: 5.7GHz
Frequency Stability ±1MHz (max) @ room temp.
±2.5MHz (max) @ -40°C ~ +60°C
Frequency Phase Noise -75dBc/Hz (typ) @ 1kHz @ room temp
-93dBc/Hz (typ) @ 10kHz @ room temp
-105dBc/Hz (typ) @ 100kHz @ room temp

Conversion Performance at Room Temp
Conversion Gain 60dB (min)
Gain Flatness ±5dB (max) over operating band
±1.5dB (max) / 36MHz
Noise Temperature 25°K(max)
Image Rejection 40dB (min)
Cross Polarisation 20dB (typ)

Thanks for the help!

Karis

We will take over the world-One Sat reception at a time!

Llew

Low noise wins over gain, whether C or ku band LNBs - you can increase gain with in-line amplifiers, but you can't lower the noise level.

Llew

Celebrating Ten Years Of The Forum As A Founder Member

karism

Thanks for the reply! Great stuff

Should i be concerned that a 13K LNB has a lower conversion gain than my MTI ( 60db min ) some of them have a 55db min conversion ?

We will take over the world-One Sat reception at a time!

Llew

Don't think 5db is going to make much difference. Don't have aany experience of C-band stuff, but whatever terms are used, the principle should be the same.

Llew

Celebrating Ten Years Of The Forum As A Founder Member

Turok

Hello Karism!
look in the topic cband twin lnb,here i have explained your question!