Bei aliexpress bekommst du für ca 228 US$ ein K-Band LNB mit Feed.
Allerdings hat es eine LOF von 18250 und ist nicht für das D-Unterband.
Wichtig ist aber das Feed, das viel schwieriger zu bekommen, und bei namhaften Firmen nicht zu bekommen ist.
Im B-Unterband gibt es natürlich weniger TV, aber an Signalen mangelt es jetzt nicht.
At aliexpress you can get a K-band LNB with feed for around US$ 228.
However, it has an LOF of 18250 and is not for the D sub-band.
What is important, however, is the feed, which is much more difficult to obtain and cannot be obtained from well-known companies.
In the B sub-band, of course, there is less TV, but there is no shortage of signals now.
I need help, I want to start exploring Ka band but it's hard to find an lnb + feed, does anyone here on the forum have any extra they want to sell or can tell me where to find a new or used lnb Ka band D (21.20 / 22.20GHz)?
I will be grateful for any help.
It depends on how much you can pay and how much work you are happy doing. The 9000 series LNBs from Norsat (and the same types from XMW) are around US$800 but as femi said, feeds are more difficult to obtain but you can get some from XMW. You might be lucky to find and XMW/Norsat on Ebay at a much better price. Go for a PLL if you can. Feeds for prime dishes are harder to find than for offset.
However, the cheaper way is to use a Gilat AN8004 ODU (OutDoor Unit) from a broadband system. For band D you can either just remove the polariser (to convert it to linear polarisation (used on 7E & 16E) and plug in to the RX port or remove the LNB and cut out the OMT (the front part of the unit). The pictures show an AN8002 which looks very similar but covers band B. You can find these ODUs for around 30-100GBP for the AN8004 on Ebay by searching for 'satellite broadband', 'satellite internet' etc (much less for the more common AN8002). You will often have to look carefully at the pictures to identify the ODU model. Do not be tempted by the Viasat ODUs as they are not suitable
If you decide to remove the LNB, which makes it much easier to rotate the polarisation, there is quite a lot of information on satellites.co.uk
ODU - RX side lid removed, feed & polariser
AN8002 complete (AN8004 for band D looks similar)
Open ODU showing screws that allow LNB to be removed
If you want to master the Ka band in circular polarization, I advise you to LNB with a local oscillator frequency of 20.45 GHz:
At the same time, you will be able to receive signals of both circular polarizations in the ranges of 18.0 - 20.2GHz and 20.7 - 22.9GHz with one LNB.
If you want to master the Ka band in linear polarization, I advise you to LNB with a local oscillator frequency of 20.25 GHz:
At the same time, you will be able to receive signals of both linear polarizations in the ranges of 17.8 - 20.0 GHz and 20.5 - 22.7 GHz with one LNB. In addition, from the same LNB you can receive the Ku band in linear polarization (local oscillators 9.75 and 10.6 GHz).
I would definitely recommend this LNB for all owners of offset antennas on a polar suspension (without a "revolving" mechanism for changing heads).
Since the respected femi has an antenna with a "revolving" mechanism for changing heads, I would advise you to purchase both LNBs - then the entire frequency range for all four polarizations would overlap.
strannik I'm not sure if the 20.45GHz LO LNB has ever been easily available. Most of the band D TV is linear polarised in N Europe.
The Ka/Ku LNBF would be ideal but they rarely come on to the used market and Inverto have not made any for a long time, as far as I know. How would it cover 17.8-20?
Here is a picture of a band D Gilat LNB fitted to a rotating mount for skew control. It shows the cut-down front of the original ODU which separates the OMT from the bulk of the donor unit. The 2nd co-ax is the LO reference feed to enable the LO to be set remotely and locked to a GPSDO reference. The band D Gilat can cover about 20.5-22.4GHz with the right IF & LO. No modifications are needed to this LNB LO if you only want 21.4-22GHz.
But femi , as far as I know, has an antenna with a "turret" LNB change mechanism, and it is unlikely that such a design can be installed on it.
I think that he will express his opinion on this matter.
How will he cover 17.8-20?
The answer comes from many years of work done by my friend stephan94 using my IQmonitor program,
which allows you to receive signals whose frequency is lower than the frequency of the LNB local oscillator.
And the TBS 6983 card allows you to process RF (intermediate) frequencies in the range of 250 - 2450 MHz
20.25 - 0.25 = 20 GHz
20.25 - 2.45 = 17.8 GHz
Shown here is one of the results of this work.
And here is one of the latest examples of reception at frequencies below the local oscillator frequency: 
CodeThanks @s-band can you tell me if XMW feeds fits with Norsat lnbs?
XMW produced two Feeds, one for the lower, and the other for the higher K-band.
At the last time, they have only the first type.
Both types working from E- to D- Sub-Band!
The Norsat LNBs have a WR42 flange and fit to the XMW Feed.
On the left my replica, on the right the original XMW
The answer comes from many years of work done by my friend stephan94 using my IQmonitor program,
Thank you. I am surprised that the image response of the LNB is so high. I doesn't sound like there is much filtering. If there is very little rejection of the image, the image noise will be significant and will reduce the sensitivity (image noise adds up to 3dB to the noise figure). It would be interesting to se inside one of the Ka/Ku LNBs.
Regarding the Gilat AN8004 it seems to be a good option that I was unaware of, can you confirm that it is effective for sub-band D with quality?
Measurements of Sun noise showed that the Gilat was as good or slightly better than an XMW. All my band D reports were done using the Gilat.
What f/d have Gilat feedhorn from 8002-8004 ODU ?
I'm not 100% sure. The feeds on the Gilat look the same as those sold with a system by Skyware which used the same dish I'm using (Prodelin/GD 3122) which has an f/d of 0.8 . There is a similar dish with an f/d of 0.6 so no guarantees. However, the Gilats work OK for me and people with f/d of 0.6.
Ich habe hier eigentlich nur auf die Anfrage von bol@nov geantwortet.
Dazu gelernt habe ich trotzdem wieder etwas.
Allerdings habe ich das Polarisationsproblem auf meiner PF Antenne. Eine Lösung mit einen Stellmotor, der die gesamte Hohlleitereinheit dreht wäre das sinnvollste.
"trust" baute schon mal so etwas. Allerdings war es eine C/Ku Kompromisslösung. Ein umsteckbares System für verschiedene Frequenzbereiche würde das noch perfektionieren.
I actually only answered the request from bol@nov here.
Still, I learned something about it.
However, I have the polarization problem on my PF antenna. A solution with a servomotor that rotates the entire waveguide unit would be the most sensible.
"trust" built something like this before. However, it was a C/Ku compromise solution. A switchable system for different frequency ranges would perfect that.
@странник:
На самом деле я только ответил на запрос от bol@nov здесь.
Тем не менее, я кое-что узнал об этом.
Однако у меня проблема с поляризацией на антенне PF. Решение с серводвигателем, вращающим весь волноводный блок, было бы наиболее разумным.
"траст" построил что-то подобное раньше. Однако это было компромиссное решение C/Ku. Переключаемая система для разных частотных диапазонов улучшит это.
On the left my replica, on the right the original XMW
Can I see your irradiator from below and from above?
Did you make a copy yourself? What drawings?
thanks for answers
Is it possible to modify this lnbf to linear polarization?
I think it's possible.
It is necessary to steam the cap and remove it from the irradiator, and remove the polarizing plate from the waveguide. It comes in the form of a rhombus or a double dovetail made of plastic.
Heat the cap with a hair dryer and put on the irradiator.
Is it possible to modify this lnbf to linear polarization?
If it is the same design as their Saorsat band B LNB, then it will have a septum plate. The picture shows one which had the feed removed. I would not recommend the Saorsat LNB as there are much better options unless you want upper band B circular. Note that Saorsat itself on 9E has a very tight beam covering only Eire, some of NI and a small part of western England/Wales.
The plate is part of the casting and could be removed with care but the electronics should be removed first.
Hello bol@nov, is this LNB available anywhere? If yes, at what price. Thank you greetings Wolfram
So far I haven't found anything but this lnb seems to be a good option for sub-band D that no one had mentioned before.
Can I see your irradiator from below and from above?
Did you make a copy yourself? What drawings?
thanks for answers
Bild flanschseitig, bedingt durch den Fräser ist der Hohlleiter etwas abgerundet.
Die Maße sind vom Original.
Im Gegensatz zu anderen meiner Bastelarbeiten zeigt dieses Teil keinen empfangsmäßigen Unterschied zum originalen XMW Feed.
Picture on the flange side, due to the milling cutter, the waveguide is somewhat rounded.
The dimensions are from the original.
In contrast to other of my handicrafts, this part shows no difference in reception compared to the original XMW feed.
If it is the same design as their Saorsat band B LNB, then it will have a septum plate. The picture shows one which had the feed removed. I would not recommend the Saorsat LNB as there are much better options unless you want upper band B circular. Note that Saorsat itself on 9E has a very tight beam covering only Eire, some of NI and a small part of western England/Wales.
The plate is part of the casting and could be removed with care but the electronics should be removed first.
It's a sad message if the depolarizer in the LNB is really made in the form of a "fish fin".
The fact is that such depolarizers separate the waves of orthogonal circular polarizations into two quarter-wave probes, which are coaxial to each other and are printed on the electronics board. This is clearly visible in the photo.
Therefore, if you disassemble the LNB and carefully remove the partition, then without it it will be possible to receive only one linear polarization on both L and R channels simultaneously.
The only thing that can inspire optimism is that the LNB body is vertically much closer to the waveguide than the top of the black plastic casing to its cylindrical neck.
This geometry is much closer to the design of an electronics board with orthogonal probes and a depolarizer in the form of a plastic plate.
If you can't find an answer on the Internet, try to remove the casing (it's on latches) and compare the metal case with the waveguide with the one in the photo.
I offer you my apologies. Due to poor eyesight, I have a large forum display scale on my monitor, and when I wrote the answer, I saw only your nickname.
In addition, I am constantly tormented by remorse that I did not give you the promised information on the phase centers of the LNB and the inefficiency of pyramidal horns. Apparently that's why I subconsciously gave an answer to your name. Please forgive me.
And I will definitely write articles about "revolving" mechanisms and placing LNB on them.
Thank you for your answer on the design of the irradiator.
In 1989, I also independently made a smooth transition from a round waveguide to a standard rectangular flange from aluminum.
And I also plan to talk about this. Including about the problem of rotation by 90 ° of the plane of polarization of the wave and self-made orthomodes (tees for orthogonal polarizations)
All health and success
Therefore, if you disassemble the LNB and carefully remove the partition, then without it it will be possible to receive only one linear polarization on both L and R channels simultaneously.
Ah, yes, my mistake, I should think more clearly before posting. I still had 'squeezed pipe' polariser in my mind. Here is a very good article on septum polarisers: http://www.w1ghz.org/antbook/conf/SEPTUM.pdf
This is the septum from an AN8024 ODU:
It rotates through 180 degrees to set the polarisation. The TX guide feeds one side and RX the other. This is the WG output:
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