Comtech 13 foot Satellite dish Ku Feedhorn + attachments

[rrob311]

I have no idea what these extensions are for this feedhorn setup. I am also not sure where to get LNB for the Ku side of it. I think someday I would like to use this for Ku just to see what fringe signals I can pull in with it. Can anyone explain what these adapters are for? I don't have a manual and everyone I talked to at ComTech is clueless about this.

 

[brex2001]

Definitely save the Ku feedhorn adapters - you might want to adapt these to a Channelmaster or Prodelin feedhorn if the round flange is C120 pattern.
I was looking online for waveguides like these today.:

 

[rrob311]

So what is a waveguide? Do you mean convert the assembly to fit a different dish? the dish for this has 2 cables it hangs from and 2 poles below that support it.

 

[brex2001]

In pic 3 you just see the round flange of the "waveguide" held on with 4 screws. That could be C120 size like for the feedhorn of some Ku dishes. Yes, convert the part that goes from round to rectangular to another dish for Ku only.

The "waveguide" is what conducts the microwave radiation to the LNBs You have 2 rectangular openings for LNBs at right angles to each other, IF the pattern is the same as for something like a Norsat 4106A LNB(or Eagle Aspen 770 KU). The square bolt pattern/waveguide size for these LNBs is WR75.

 

[rrob311]

That square flange is like a little over 1 inch square. It is pretty small. I will have to take some measurements and see what I can get. Do you know what the angle adapters are for? It has a motor on it to adjust skew so I think I will just run one. The guy I bought the dish from said he used the dish for uplinks.

 

[guacharaca]

Wow. Cool Feedhorn. Neanderthal, but cool. That is the largest polorator I have ever seen.

 

[Magic Static]

It's a KU orthomode feedhorn and scalar with adjustable skew. You would put two single polarity ku lnbs on it. One would be vertical and the other horizontal. Two cables to a multi-switch. You don't really need the adjustable skew working to use it.

 

[brex2001]

It's a KU orthomode feedhorn and scalar with adjustable skew. You would put two single polarity ku lnbs on it. One would be vertical and the other horizontal. Two cables to a multi-switch. You don't really need the adjustable skew working to use it.

Thank you for restating this.
Yes he would need the adjustable skew - the dish doesn't have declination to compensate for azimuth, if he uses that waveguide with the Comtech dish. But, using 2 LNBs for H&V & the multiswitch would allow fast polarity changes.

 

[rrob311]

The Cband setup that is on the dish now is similar. But the piece that was in between the scalar and lnb was the cause of my reception issues. I posted pics of that setup on the "C band reception woes" thread. If anyone can shed some light on what happened it would be much appreciated.

As for this setup I found a couple of LNBs from the UK on febay that might fit it. Not sure which one I want though.

 

[brex2001]

Here's a PLL LNB you may want to consider - Ebayer in Israel: item #200605372489.
$49 each for Zinwell Ku LNBs, PLL freq L.O., 0.7 dB noise, +/- 30 kHz stability
PDF file link:

[FONT=Arial, Sans-serif]http://www.zintech.com.tw/uploads/product/ZK-PF1.pdf[/FONT]

Just bought 2 - Eagle Aspen 770s(not PLL) @ Volunteer Satellite are $49 ea. Norsat 1207As PLL LNBs are $300 each!