• Yesterday I purchased AX techologies Black Buster Quattro and I am really sad.


    I wanted Quad, but quattro is OK. Duad delivery on every output enythig what you ask (by manipulating polalry voltage and tone). Quattro deliver on every output own signal: Hor-Low, Hor-High, Vert-Low, Vert-High. so, need to connect sdr and minitouner to correct output and unused (high band) connectors can be used for LNB supply and Ext Ref clk in.

    The biggest problems it that this LNB don't have PLL and quatz. They are using ceramic oscillators. So no ext ref clk in possible. We careful before purchasing LNBs.

    Here are few pictures of my problem. Be smart and don't make my mistakes.

  • I will try it.

    PS: Thanks to YL3JG, I have PLL locked SDR receiver in GNU Radio.

    This is only concept right now, but it nicely lock to carrier. Later I will test it with existing Es'Hail-2 beacon.

  • Some time ago I purchased AX technology Opticum Twin Black Buster LNB.

    Absolutely different internals compared to Quattro LNB. I don't have PCB picture, but it looks 90% like this Octagon OTSLO 1609 LNB, except tah Opticum don't have 10.7-12.75 GHz BPF and different PSU doide case, so I hope it will work nicely on 10.49 GHz. So this LNB will be starting point for P4A NB and WB.


  • To remain on topic (RHCP): last weeks G0MJW, M0EYT and I were busy designing, modelling and building prototypes of alternative 2.4 - 10 GHz dual band feeds.

    There are several variations of the same theme, but I wanted to have a design without needing lathes or CNC-machines. The result is a (well known) 'cropped' patch, sized and matched with a waveguide in the center.

    It took some time to model the correct position of the feedpoint as the waveguide seems to introduce some 'issues', making it not trivial to find the proper position to have (what I call) the 'S11-balloon' circling around Z=1 in the Smith Chart.

    Attached a picture of sweeping my interpretation of a prototype, which we name ' 29-16° '. Return Loss (RL) could be improved even more with some tweaking of the patch height at the feedpoint position.

  • Here the finish mechanical design..next to match the helix with the spectrum analyzer. Of cause this is just for the try an DRO lnb. PLL will follow in final design.

    I will post again when I have more informations..

  • DD0KP wrote: Raf I am just discussing with the company b.e.s.t. in Germany. They have rocket LNBs with PLL!!

    Definitely not! I have procured such a LNB, and behold: No PLL to recognize, no Quartz ... Only two DRO :-(

    Be careful with LNB´s from B.E.S.T

    73's Robert

  • DD4YR, I really understand you. I had similar problem with quattro. For now I will stay with Twin PLL LNB with DIY hole for external clock in cox cable.

    But... Aliexpress could be promising. I'll give a try.

  • Hmmm... I bought a rocket LNB a while ago, advertised as 'PLL' but with a DRO after I opened it. However, the words 'Quartz Crystal Controlled' (or similar) were not in the casing.

    So, your situation is more misleading. I would address the seller/company and at least demand a refund.

  • With all LNB types (especially the unspecified ones) it appears to be customary to change the electronics while still selling them under the same brand name and type number.

    So when person #1 buys and determines to be a PLL LNB with 25 MHz reference, person #2 may find a DRO based LNB and person #3 may find a PLL LNB with 27 MHz reference.

    All with (about) the same external appearance and sold under the same name.

    I would think the trend is towards PLL type, and it seems also towards 25 MHz reference. So whenever you buy an LNB try to get new stock by ordering from a company with high turnover or close to the source.

    Especially when searching all the internet for an LNB no longer produced or hard to get, you probably have increased risk of getting an early type that is not usable.

  • pe1chl , I understand that, and you're right. But, the housing with PLL and quartz stabilized stickers to label and then obstruct other hardware is already brazen ....

    I will act as Remco recommends...

    @YL3ACK, I still work with a single PLL LNB from GOLDEN Media (GM-201), removed Quarz, drilled hole for coax with GPS sync clock. Works perfect.

    The only problem is the weather resistance and waterproofing, certainly not long-term stable... :-)

  • DD4YR Robert can I use your to pictures for my discussion with the b.e.s.t. team ? On the phone they told me the design is mad by them in Germany and all types have PLL.

    I will then report here my results.. Very interessting

  • By the way, the PLL from GOLDEN Media locks in stable over a very large area. Better than the RCA's in the OCTAGON's. I went so far up the GPS stabilized PLL frequency (26.335 MHz) so I could still receive the 10706 MHz beacon at 435 MHz. The S / N was not worse. The same way in the other direction to convert the 10.5 GHz transponder to 1286 MHz.

    The best PLL I've ever had in my hand. :-)

  • Here my finished outdoor design. LNB and Helix in one dish. Only the measurement of the helix will be done next week. Then I post the results.

  • Hello all,

    because a OM has asked me about the construction details of my helical dish feed i packed some detail photos into a Zip archive.

    Maybe someone here finds it useful for a diy helical dish feed.

    In the also enclosed PDF the calculations for the dimensions are described. Document fm W1GHZ.

    vy73 DB8TF

  • There are many ways to get the right dimensions.

    Helical feeds are really forgiving about small changes in dimensions.

    I found the hardest part of the assembly to get a good SWR, but after some fiddling with the small metal plate near the N-connector i get a good match.

    How this feed will perform in practise we'll see when we are allowed to TX to EH2.

    vy73 DB8TF