Prodelin 3.8 VSAT offset dish antenna

[Reenx]

hello everyone, I just bought prodelin 3.8 offset dish , but only dish, I don´t have feed rods and feed support,
does someone have a similar dish?? model prodelin 1383
or any idea how can I calculate?

thanks for your support

 

[RimaNTSS]

First of all, congratulations! Assemble the dish and measure it's working area, widths and height (with the precision up to 1mm), and depth in the very middle with the precision up to 0,1mm. And also check whether the mirror has some warpage. And then all the parameters of the dish can be calculated.
Could you show some pictures?

 

[nelson61]

I would have killed to get one a few years back.

I build a custom ku similar size and have lost my files

But, you can do calculations to figure it out,
The offset is likely the standard 22.6 degrees (the earth rotational offset angle)
The long axis of the offset antenna will likely be = to the radius of the circular antenna the offset was derived from.
The bottom edge of the offset is the normal center of the circular antenna
The circularantenna radius or diameter sets the focal length.

I found an old picture of some of the calculatons that might help you and another that illusttates how the offset is cut it's corresponding circular equivalent
i will keep hunting fto see if I can find the file with all the calculations in an excel format,

 

[armadillo_115]

	This appears to be the manual: PRODELIN 3.8M ASSEMBLY MANUAL Pdf Download | ManualsLib

 

[a33]

The long axis of the offset antenna will likely be = to the radius of the circular antenna the offset was derived from.

If you'd say the short axis would likely be about the radius of the primefocus circular dish antenna it was cut from, then I would heartilly agree.
Or do we, in fact, disagree?

Reenx : though the offset angle might well be 22.62 degree, as the manual says, do the RimaNTSS measurements!
And don't use the Parabola calculator 2.0 or the satsig calculator that you find on the internet, as they have errors.
Parabola6 is faultless, I found, and also a french xls. (And my own calculator, BTW, but that I use only on demand.)

greetz,
A33

Edit: BTW: I never suspected a connection between satellite dish ofset angles and the earth rotational offset angle?

 

[Reenx]

Size
Vertical 400 cms
Horizontal 380 cms
Depth 37 cms

 

[Reenx]

My dish

 

[RimaNTSS]

Is not it exactly the same antenna near yours? Then you probably just make a copy of the feedarms and LNB holder.
Anyway, there is a sketch (not a drawing) with all data you need. to know about your dish.

 

[a33]

Just another example where the offset angle in the manual is not right at all?
18.2 degrees, instead of the seemingly precise 22.62 degrees in the manual?

Ooooops!

Greetz,
A33

Edit: I just hope the exact measurements of the paraboloid surface are 400.0 cm, 380.0 cm, and 37.0 cm (so all three measurements, without the rim)?
Or else you arrive somewhere in the neighbourhood of the focal point, not at the focal point.

 

[Need2learn]

hello everyone, I just bought prodelin 3.8 offset dish , but only dish, I don´t have feed rods and feed support,
does someone have a similar dish?? model prodelin 1383
or any idea how can I calculate?

thanks for your support

You can do this just order the LNB Assembly for the Prodelin 1383..