[sdf_row id=”sdf-row-1″][sdf_col id=”sdf-col-1″ width=”1/3″][sdf_image id=”sdf-element-0″ module_width=”1/1″ title=”” alt_text=”” image=”http://christiandish.com/wp-content/uploads/2019/09/KU-band-LNBF-10750.gif” has_retina_version=”no” top_margin=”” bottom_margin=”” entrance_animation=”No” entrance_animation_duration=”” image_alignment=”left” image_size=”sdf-image-md-12″ image_shape=”square” image_border_radius=”” lightbox=”no” lightbox_ad=”no” link=”https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=FDHYJYHW4VVPN” link_title=”” target=”_blank” nofollow=”no” image_hover_effect=”” image_hover_title=”” image_hover_subtitle=”” class=””][/sdf_image][sdf_blank_spacer id=”sdf-element-1″ module_width=”1/1″ height=”100px” class=””][/sdf_blank_spacer][/sdf_col][sdf_col id=”sdf-col-2″ width=”2/3″][sdf_headline id=”sdf-element-0″ module_width=”1/1″ top_margin=”” bottom_margin=”” title_heading=”h1″ font_family=”Georgia,serif” font_size=”18″ line_height=”” letter_spacing=”” text_color=”” text_alignment=”left” entrance_animation=”No” entrance_animation_duration=”” rotate_words=”no” rotator_delay=”1000″ rotator_separator=”” fit_text=”no” fit_compressor=”” fit_min_font_size=”” fit_max_font_size=”” class=””]Why do LNBF’s fail?[/sdf_headline][sdf_text_block id=”sdf-element-1″ module_width=”1/1″ top_margin=”” bottom_margin=”” max_width=”” text_alignment=”left” font_family=”Georgia,serif” font_size=”12″ line_height=”” text_color=”” entrance_animation=”No” entrance_animation_duration=”” link=”” link_title=”” target=”” nofollow=”no” class=””]
So why do LNBF fail on a satellite dish?
The big question is “Why do LNBF’s fail” on satellite receiving antennas like the free to air KU-band or the major commercial satellite dish antennas, especially after a rain storm or a lightning storm has occurred?
To get a little foundation on what they do we need to know a little bit on how they work and are there different types of LNB’s. A Low Noise Blockdown Feedhorn (LNBF’s or LNB) is that little object in the very front of the satellite antenna (dish). The antenna reflects the signal to the f the LNBF and the high-frequency signal reflected from the antenna is then converted to a lower frequency that is carried via your coax cable to the LNB input of your receiver inside the home. They are manufactured for C-band and Ku-band dish and they come in an array of sizes. They also come in different frequency output ranges, for example, the most commonly used in our industry is the standard 10750 MHZ LNBF, buy they also come in 9750-10600 MHZ and so on.
The neat thing about the FTA satellite receivers is that you can use just about any LNBF due in part that you can change the input frequency on the receiver. Okay with that out of the way the main reasons why LNBF’s fail is because moisture has penetrated the electronics on the main housing of the LNBF. Other words water damage has occurred. Below I will provide you with 4 subheadings as to the major reasons LNBF failure occurs.
Lightning damage
By far lightning damage has one of the most destructive forces that cause failure on many levers, especially on electronic devices in home or business. By far the most effective way to try to prevent this problem is by grounding the coax line coming from the satellite dish to the home. It is not a full proof procedure because as you know lightning is composed of very high voltage levels. It is a good practice to make sure that your satellite system is properly grounded from the very beginning and if it is not, do it now to prevent future damage. Televisions, DVD players, sound systems have been damaged just because there is no surge protectors and no proper grounding has been practiced. I recommend that you check with an electrician or your local government code procedures for properly grounding antennas. Here is something that you can do to help you test to see if your LNBF or receiver are working fine. Start by disconnecting the coax line going into the LNBF and use a voltmeter to test for 18vdc on the horizontal polarity and 13vdc on the vertical polarity. You will do this by grounding the black probe to the F connector and the red probe will touch the center pin coming out of the connector. If your good there than replace the LNBF, assuming that your satellite dish has not gone out of alignment. You can usually tell when your receiver indicates to you that you do not have signal strength from the LNBF and no quality. Here is a video that I produced to help you diagnose the problem on the KU-band FTA satellite system. Click here for video.
Loose F connector
Here is the problem with a loose F connector and the problems that you can experience because of it. When you have a loose F connector on the LNBF fitting at the end of the LNBF unit failure will occur, because you do not have proper grounding to the LNBF housing. A loose LNBF to F connector can sometimes overheat the fittings and cause a melt down or just burn the electronics inside the LNBF. I have also seen receivers damaged because of loose F connection on the LNBF and the back of the receivers F connection. Proper tightening is needed and it usually takes a good finger tightening or a specially designed torque wrench for F connectors. And if your tighten the F connector to much you will spin off the Barrel connector on the end of the LNBF. Don’t use a wrench to torque the F connector unless it is specially designed for it. I can’t tell you how much damage I have seen over the years because of over tightening.
Water damage at the LNBF connection
Can water damage an LNBF? Yes!, Water damage is another cause for LNBF failure and that can occur in different ways. One of them is dealing with the F connector on the end of the LNBF, a loose F connector can allow water to ingress into the F connector under the LNBF and into the connection under the LNBF. Water can create corrosion in the connector and eventually rust and cause a short grounding the voltage coming into the LNBF, possibly damaging your receiver as well. The best way to prevent this is to give the F connector a good finger tightening and use tape or using shrink tubing on the connections.
Cracked or Missing LNB cap
Why is the LNBF front cover missing from the front of my unit? Here is what I have been told by plastic manufacturing experts. The main reason the caps dry up and eventually fall off is because there is no UVA or UVB protection on the plastic. Some plastic manufacturers use to use lead and some hazardous compounds that protected the plastic, but in order to import the LNBF’s the plastic has to meet safety regulations, etc. The first thing that need to do is a visual inspection of your LNBF (KU-band satellite antenna) and see if the front cap of the LNBF is not missing, if it is, it will need replacing right away. The LNBF is located on the satellite dish itself outside mounted on the eve or on a pole on the ground, most people know where their FTA satellite dish is located. The LNBF is the device located in the front of the satellite dish and supported by an arm of one kind or another. If you can visually see it missing that’s will tell you right away a new one will be needed, but perhaps it is not missing and the cap may have small cracks around the cap in front of the LNBF facing the dish. If you detect or feel that the cap is cracked or dried up a new LNBF is recommended. The problem with a dried up or cracked LNBF is that eventually water will Ingress its way into the electronics inside the housing and creating a short inside the LNBF. A short can possibly damaging your receiver by taxing the power supply causing it to overheat and dry out components in the receiver. You can purchase a new LNBF at: PayPal shopping
How often do you replace the LNB
There’s really no rule of thumb that dictates how often you should replace your LNBF. I personally make it a practice of replacing my LNBF’s about every 5 years. Here is the reason why! I don’t like replacing my expensive receiver if the LNBF fails. The second reason is that the LNBF’s are so cheap it’s not worth taking the risk of damaging the receiver. I like to leave a spare or keep a spare LNBF available just in case there is a failure.
Best LNB to use?
There are many brands and makes out there that manufacture LNBFs, but I personally like the GEOSATpro SL1PLL LNBF with phase lock loop technology.
Here are the specs to the LNBF that I carry.
PLL (Phase Locked Loop) LNBs are typically only found in high end commercial systems and historically cost 10, 20 or even 30 times or more than the LNBFs produced for the residential customers. The SL1PLL is a breakthrough LNBF, built with the highest grade materials and the latest RDA chipset and PCB technology. Recent technology allow for cost effective production of PLL LNBFs with lower current draws, lower heat generation, lower internal noise generation and increased performance.
The SL1PLL has been designed to meet the requirements for commercial applications and the most demanding satellite hobbyist. Reliable reception of digital HD MPEG4 channels with low symbol rates or high FEC requires an LNBF that excels in several performance benchmarks. The SL1PLL has exceptional flat gain across the 11.7 – 12.2GHz frequency range, features an excellent phase noise rating with low internal noise generation during signal conversion / amplification and stable frequency tuning for narrow bandwidth signals.
The SL1PLL has been designed to meet the requirements for commercial applications and the most demanding satellite hobbyist. Reliable reception of digital HD MPEG4 channels with low symbol rates or high FEC requires an LNBF that excels in several performance benchmarks. The SL1PLL has exceptional flat gain across the 11.7 – 12.2GHz frequency range, features an excellent phase noise rating with low internal noise generation during signal conversion / amplification and stable frequency tuning for narrow bandwidth signals.
SL1PLL LNBFs are factory tested and warranted to be completely WaterProof. This means that the SL1PLL LNBF has been completely immersed in water for a ten minute test to insure proper assembly, fitting and component integrity. Most LNBFs are only water resistant or water shielded and are not tested to provide years of continued operation in the most extreme environments.
GEOSATpro SL1PLL Product Specifications
Frequency Range 11.7 – 12.2GHz
IF Range 950 – 2150MHz
LO Frequency 10750MHz
LO Drift +/-300KHz (max)
LO Phase Noise -70dBc/Hz@1KHz -80dBc/Hz@10KHz -100dBc/Hz@100KHz
LO Spurious Noise -50dBc
Noise Figure 0.5dB@25°c
Conversion Gain 60dB
Gain Variation 2dB
Gain Flatness 0.55dB/27MHz
Image Rejection 42dB
Isolation 22dB
P1dB 1.5dBm
Output VSWR 1.5:1
Polarization Switch V = 12 – 15vdc H = 17 – 20vdc
DC Current Draw 120mA (max)
Temperature Range -30°c – +60°c
FD Ratio .5 – .6
UV Rating 15 years
Waterproof Test 60°c@10 minutes (min)
Visit our website to purchase your LNBF today.
Shop via PayPal
[/sdf_text_block][sdf_cta_button id=”sdf-element-2″ module_width=”1/1″ top_margin=”” bottom_margin=”” button_icon=”no” button_icon_position=”icon-left-side” entrance_animation=”No” entrance_animation_duration=”” button_layout=”center” subtitle=”” style=”danger” size=”btn-lg” link=”https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=FDHYJYHW4VVPN” target=”_blank” nofollow=”no” class=””]Order a new LNBF[/sdf_cta_button][/sdf_col][/sdf_row][sdf_row id=”sdf-row-2″ last=”yes”][sdf_col id=”sdf-col-1″ width=”1/1″][/sdf_col][/sdf_row]
