Here is a Review/Test Results of the BSC421 performed by Anthony Dunnett of New Zealand, posted with permission - Thanks TonyFirst the BSC421 Pics and Specs from DMS:
Specifications:
Noise Figure : 13K
Input Frequency: 3.4 to 4.2GHz
Output Frequency: 950 - 1750MHz
Polarity Switch : Vertical @ 11.5 - 14.2 Vdc
Horizontal @ 15.5 - 21.0 Vdc
Output Connector : F Type, Female
Output V.S.W.R. : 2:0:1 max
L.O. Frequency : 5.15GHz
Conversion Gain : 65dB Typical
Phase Noise : -75dBc/Hz @ 1kHz
Image rejection 40Db Typical
And here is the Test Results from Tony at jayxhttp://www.jayx.co.nz/DMSI%20LNB.html
Firstly we are not going to criticize other makes of C band LNBF’s. JX Satellite has been looking for a C band LNBF which would provide them with a little extra margin when using a 90cm offset dish for IS5 and for a 1.8m for Asia sat 4.To be very fair the current 15k Pacific lives up to its description and it performs very well for 98% of the applications we require.
The BSC421 13K is the next step up it also performs up to our expectations as the spectrum analyzer pictures will show. The test comprised of a 1m offset dish locked and peaked on IS5 @ 169 degrees East.
The C band demodulated output at 950 to 1750 MHz was plugged into a two way splitter with the power pass into a Mirchee Satellite receiver as they can hold both signal and quality in an easily read window. The second output port was plugged into an Advantest commercial spectrum analyzer and set up on IS5 output frequency of 4160 GHz /26478 M/s with a fec of ¾.The Pacific Lnbf was re adjusted using an Avcom PS47 D for maximum output and cross pole null.
Pacific 15K = (Minus) 55dbm 
BSC421 13K = (Minus) 49dbm 
Neither of the LNBF’s was fitted with a conical feed horn or Scalar rings during the test the Lnbf was positioned in the plastic feed horn holder as per the picture below:
The BSC421 is an accurate 13K C-Band LNBF made specifically for DMS International of the USA. This is a compact, lightweight, weather-proof LNBF with High Gain Output. It has excellent D.R.O. stability and Low Phase Noise for digital applications as well as Analog. 3.4 to 4.2 GHz extended frequency, with L band output in the 950-1750MHz range. Voltage controlled (H/V) switching 13/18V. A true 13K Noise Figure with 65dB Gain, and comes complete with the Scalar Ring and a dielectric plate for circular polarized satellites such as the Russian Gorizont and Express and the original Intelsat class of communications satellite.
Test results:
Pacific 15K = -55Dbm or 52.2 Dbuv
BSC421 = -49Dbm or 58.00 Dbuv
dBm dBW dBuV-55 -85 51.9897
-54 -84 52.9897
-53 -83 53.9897
-52 -82 54.9897
-51 -81 55.9897
-50 -80 56.9897
-49 -79 57.9897
-48 -78 58.9897
