QO-100 Bullseye LNB Integrated 3d Printed Holder

Project: M0PPR QO-100 Bullseye integrated antenna

Please note I do not take any responsibility for this project, you do it on your own risk.

This project is a Bullseye LNB holder integrated with the 2.5 turn helical antenna for QO-100. You can just simply download the files or you can also read the article below to understand what and why I did. If you could not be bothered to read the article below, then do not complain it did not work for you. If you decided to read and then you want to complain – I do not care either 🙂

You need to print our on the paper 1:1 PDF drawing and check against your LNB holder – see pictures below to see what is to do.

I would consider tweaking the holder to match YOUR LNB holder, however under one condition: you will send me a very detailed drawing – see samples at the very end of this website. Also I will need a link to the antenna seller’s website so I can have it for the reference.



Initially design for this 40cm antenna:
QO-100 Bullseye LNB Integrated 3D Printed Holder for 40cm dish.

Arm tube diameter: 22mm

Files:
Assembly Drawing with BOM – PDF
Main Holder – STL
Cover – STL – common for all designs
Clamp – STL – common for all designs
Reflector 1:1 – PDF – common for all designs
Matching transformer – 87mm x 26mm 0.5mm thick copper – see pictures below – common for all designs
Helix Winding Jig – STL – common for all designs

See article below for details!




Initially design for this 40cm antenna:
QO-100 Bullseye LNB Integrated 3D Printed Holder for Gibertini OP40 40cm dish.

Arm dimensions: 30 x 15 mm

Files:
Assembly Drawing with BOM – PDF
Main Holder – STL
Cover – STL – common for all designs
Clamp – STL – common for all designs
Reflector 1:1 – PDF – common for all designs
Matching transformer – 87mm x 26mm 0.5mm thick copper – see pictures below – common for all designs
Helix Winding Jig – STL – common for all designs

See article below for details!


Initially design for this 65cm antenna:
QO-100 Bullseye LNB Integrated 3D Printed Holder for 65cm dish.

Arm dimension: 20.4 x 20.4 mm

Files:
Assembly Drawing with BOM – PDF
Main Holder – STL
Cover – STL – common for all designs
Clamp – STL – common for all designs
Reflector 1:1 – PDF – common for all designs
Matching transformer – 87mm x 26mm 0.5mm thick copper – see pictures below – common for all designs
Helix Winding Jig – STL – common for all designs

See article below for details!


Initially design for this 80cm antenna:

QO-100 Bullseye LNB Integrated 3D Printed Holder for 80cm dish.

Arm dimension: 20 x 30 mm

Files:
Assembly Drawing with BOM – PDF
Main Holder – STL
Cover – STL – common for all designs
Clamp – STL – common for all designs
Reflector 1:1 – PDF – common for all designs
Matching transformer – 87mm x 26mm 0.5mm thick copper – see pictures below – common for all designs
Helix Winding Jig – STL – common for all designs

See article below for details!

A small introduction.

I am an active user of QO-100 – the amateur geostationary satellite. I created my base station and also I have designed and made a portable version. For my base station initially I used a standard DC8PAT 3D printed antenna which is kind of great design but I decided to improve it especially for a portable work. Later on I have also replaced my base station with my own design of the LNB holder.

DC8PAT has some design issues which I eliminated:

  • you need to have a lathe (I do have) for making 3…4mm thick reflector, otherwise making it with a metal file is a disaster.
  • The antenna has no drain system, if the water (likely) will get inside – it will stay there for kind of forever! I had to drill a drain hole to eliminate the problem in the original DC8PAT design.
  • Original cover fits 3.5 turn helical antenna, however for my need of having 2.5 turn helical antenna the cover is way too big.
  • The original design (non commercial version) has a very difficult system of bonding/screwing a helix support to the aluminium base.
  • DC8PAT antenna will work correctly only for dishes 60cm or bigger – it will clash with the arm for small dishes – see some pictures below.
  • easy to snap the base holder if overtighten

  • You do not need lathe to make it – you can use 100mm 0.2mm thick copper plate. Cut it with scissors!!!
  • Weatherproof design with drain holes.
  • It comes with a skew indicator (hahaha).
  • It just looks very nice! 🙂
  • The cover thread is compatible with the DC8PAT design.
  • If for whatever reasons you decide to use 3.5 turn helical antenna, my cover is not long enough – but you can use the DC8PAT design – the thread size is exactly the same.

Unfortunately, yes.

  • antenna has no proper N connector attached to the base – I struggled to add one when use with a thin copper plate. So you need to add the coax cable and soldered it directly to the copper reflector – before (!) the reflector is fixed to the 3D printed holder.
  • The coax hole diameter is 8mm as it is designed to my favourite SSB7 aircel coax. If you need to use any thicker cable – you have to use an adaptor. Probably drilling a bigger hole (eg. diam. 10mm) will also work.
  • it was designed to work with LNB Bullseye – massive chance other brands will not fit the 3D printed holder and clamp.
  • if the size of the LNB arm in your antenna is different to what I design – you cannot use it unless you manage to modify my design to match your needs or you create any kind if an adaptor (or even you use hot glue to bond a bigger holder to a smaller LNB arm).
  • If the angle between the LNB arm and axis of the LNB is different, then you will lose some gain!! All assembly drawings provide the angles and dimensions – check them!

Pictures below show the problem with the DC8PAT and small dish:

  1. Print the main holder (choose which design you need by analysing assembly drawings in the table above). You can print 1:1 assembly drawing to check if your original LNB holder matches the design – see pictures below.
  2. Print the cover – STL HERE
  3. Print the clamp – STL HERE
  4. Make the copper reflector – 1:1 PDF HERE and some pictures below
  5. Print the helix winding jig – STL HERE, some pictures below. Please note, the design asks for the 42.3mm inner diameter of the helix antenna, which means the centre of the 3mm copper diameter is 45.3mm. However, after winding up the copper always springs back a bit and the diameter becomes 1mm greater, so the winding jig wire centre to centre diameter is 44mm (not 45mm).
  6. Wind 2.5 turn helix antenna using a solid 3mm diameter copper bar over the jig

The pictures below show how to check if one of my designs will match your LNB holder. Just print all (currently three) A4 drawings in 1:1 scale and check! 🙂

Picture above shows a perfect matching holder

Picture above shows a holder with not matching angle

Picture above shows a holder with not matching angle and wrong position of the holder

I would consider tweaking the holder to match YOUR LLNB holder, however under one condition:

you will send me a very detailed drawing – see samples below and link to the antenna seller’s website so I can have it for the reference.

2 pictures below shows how I measured a LNB holder for the 65cm dish

2 pictures below shows how I measured a LNB holder for the 80cm dish:

Two pictures below show Gibertini OP40 dish:

Gallery from users:

M0BOY – Gilbertini OP40:

2 thoughts on “QO-100 Bullseye LNB Integrated 3d Printed Holder

  1. Nigel G8AYC says:

    Excellent detailed article on your helical feed. Could I ask if you have done any comparative receive tests between using the LNB with the helix versus using the LNB on it’s own?

    Reply
    1. admin says:

      Yes – I did, but it is very difficult to say anything, as everybody’s signal is jumping up and down in the SDR console. However, I have a feeling it is about 2dB.

      Reply

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