Lak7,
OK I see. But in my reference I was averaging out the F/D ratio to .6. Below are the specs for that prime focus LNBD and you can see the F/D ratio speced at .5 - .7.
pedrogarcia,
Yes our elevations are quite low here in Hawaii. I have seen offset dishes actually pointing down! And like you said another good reason for using a prime focus.
Thanks!
Eric
For Reception of North American Satellites
KU Linear LNBF 11.70 - 12.75 GHz
Designed for Prime Focus Satellite Dishes
Low noise figure of .6dB and 60dB gain are combined in this +/-1MHz frequency stable, quality lnb.
The GEOSATpro SL1 Prime Focus LNBF offers outstanding performance when teamed with a Prime focus dish. Most LNBFs are designed for mounting on an offset reflector. These types of LNBFs are not optimized for mounting on a prime focus dish and will not provide quality signal reception in fringe signal areas.
The SL1 P will outperform any KU LNBF currently available resulting in increased Signal Quality and reliability.
Standard LNBFs work with all satellite meters and make installs easier. Perfect for viewing linear satellites in North America.
INPUT FREQUENCY RANGE
11.7 - 12.2 GHz
REFLECTOR TYPE
PRIME FOCUS
F/D RATIO
0.5 - 0.7
CROSS POL. ISOLATION
20 dB (Min.)
NOISE FIGURE
0.6 dB
CONVERSION GAIN
60 dB
GAIN FLATNESS
±0.5 dB / 27 MHz
OUTPUT FREQUENCY
960 - 1450 MHz
L.O. FREQUENCY
10.75GHz
L.O. PHASE NOISE
-55 dBc / Hz ( @ 1KHz )
-80 dBc / Hz ( @ 10KHz )
-100 dBc / Hz ( @ 100KHz )
OUTPUT POWER LEVEL
@1 dB GAIN COMPRESSION
0 dBm
IMAGE REJECTION
45 dB (min.)
OUTPUT VSWR
2.5 : 1 (MAX.)
OUTPUT CONNECTOR
75 ? F TYPE FEMALE
DC CURRENT CONSUMPTION
120 Ma
OPERATING VOLTAGE
(1) 11.5 - 14.0 V ? VERTICAL POLARIZATION
(2) 16.0 - 19.0 V ? HORIZONTAL POLARIZATION
OPERATING TEMPERATURE
-40deg C - +60deg C