Channel master c120 feed horn wanted

RimaNTSS

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Some SAT-related hardware.
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What am I missing?
As it is already said, you are missing the adapter (consists of 2 halves). If you do not find the original one, I could try to make one for you. That would be more universal than original.
 

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ozumo

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Sorry the spare one I have doesn't fit the CM feed horn.
 

ozumo

te wo tsuite
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That would be great
Sorry the spares don't fit on the CM feed horn.
5E45423F-9BA7-4419-96DD-327E4B73F42F.jpeg
CM adapter on the left, the middle one is marked 3040735-03, right one 3040666-02. All have arrows pointing to antenna.

edit: do not search for the first model number, some quite disturbing results appear :eek:
 
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Chris James

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As it is already said, you are missing the adapter (consists of 2 halves). If you do not find the original one, I could try to make one for you. That would be more universal than original.
That would be a great help many thanks
Just keep having problems
 

Lazarus

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edit: do not search for the first model number, some quite disturbing results appear :eek:


So they do (Not that I checked ....... )
 

Channel Hopper

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As per the other feedhorn thread, I will take some dimensions this weekend, the feeds that I had were for receive and transmit and may have a waveguide that is tuned for uplink frequencies. Receive characteristics in the 11-12GHz band would be less important, opening the guide diameter by 1mm may help improve things.
OK, found one (eight bolt fitting, plus slot for chip fork dielectric plate) . Internal diameter is 18mm +/- 3% which from the formulae I am used to equates to a functional frequency range of 10.5 - 12.6GHz.

The minimum cut off for a circular waveguide at this diameter is 9.75 GHz, with upper in the region of 14.5 GHz when other factors take over creating losses, making a mid-range near 12.5GHz, which suggests an increase of the internal diameter from 18 to 19mm should assist in propagating the Ku band that everyone here is used to receiving with a universal LNB.

I still doubt Channel Master have messed up the focal point of their range of antennas (much less Andrew / Raven not picking up on the flaw) once buying up stock and then manufacturing of the same items.
 

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Chris James

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OK, found one (eight bolt fitting, plus slot for chip fork dielectric plate) . Internal diameter is 18mm +/- 3% which from the formulae I am used to equates to a functional frequency range of 10.5 - 12.6GHz.

The minimum cut off for a circular waveguide at this diameter is 9.75 GHz, with upper in the region of 14.5 GHz when other factors take over creating losses, making a mid-range near 12.5GHz, which suggests an increase of the internal diameter from 18 to 19mm should assist in propagating the Ku band that everyone here is used to receiving with a universal LNB.

I still doubt Channel Master have messed up the focal point of their range of antennas (much less Andrew / Raven not picking up on the flaw) once buying up stock and then manufacturing of the same items.
All very technical but to be honest I just want my setup to work not looking for the last bit of signal right now just want a working system I’ll worry when I get my foot in the door
I think that a 1,2 meter dish will do what I want it to do for now I would like to go c-band but dish size might be a problem
I still don’t know what I’m gonna get with my 1,2 channel master dish
 

zorrin

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CM 1m20 Ku 52°E to 45°O GTMEDIA V9 Prime
CM 1m20 Ku 50°E to 45°O OCTAGON SF8008
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The black adapter, dimensions in this post:
I will post the 3D files as soon as possible.
 

zorrin

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CM 1m20 Ku 50°E to 45°O OCTAGON SF8008
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