Options for simultaneous C-band linear and C-band circular on a single 10 foot dish

[sgs]

Hi everyone,

I have got my 10' Perfect Ten dish aligned fairly well now. I am tracking from 22w to 135w for c-band and ku-band (some ku issues on certain birds, but I'll probably get a 1.2m dish for ku anyway). I'm currently using a dual C/KU-band LNBF on the dish.

I am able to receive circular polarized signals such as those on 40.5w, 27.5w, 24.5w, and 22w, if I put the dielectric plate into the LNBF throat.

However, I would like to be able to add another C-band LNBF, or get some sort of setup so that I don't have to go out to the dish and insert/remove the dielectric plate every time I want to change from circular/linear or back again.

For starters I tried put a second LNBF offset from the first one using tie wraps. I attached a scalar to a second C-band LNBF, and then tried to simply place it offset of the current LNBF (above and to the left if facing the front of the dish). I used my SH-200 meter and moved the 2nd LNBF around until I found the best position. It seems to partially work, however I need to tune it more since I'm only getting the Left (Horizontal) signals, and it's definitely weaker. It is a pain to get it to tune, and in turn to tie it down with zip ties with the angles involved.

Also, I'm not really sure I should be placing it where I am. I have the dish pointed at 45w, and am trying to pick up 40.5w with the second LNBF. It seems that I need to put it higher and to the left, when facing the dish, but I would like confirmation of this from someone who knows.

I'll probably try to take two LNBF with scalar rings and do something similar to this next (only using LNBFs instead of the older-style feeds):

http://www.satelliteguys.us/threads/193463-C-band-Linear-Circular-Orthomode-Feed-Modification

Anyway, my question is, are there any other options for having reliable c-band linear and c-band circular on a single dish without having to manually insert/remove a dielectric plate? I don't know a lot about the older style feeds, but I'm wondering if there is any option for a feedhorn that would allow for both linear and circular (both H & V, of course)?

Thanks
sgs

 

[cracklincrotch]

The only options I know of are what you already know. Either have two dishes or marry two LNBs near the focal point as Pendragon has done in that thread you've referenced. I don't know of an off the shelf feed that will do what you want.

 

[Babadem]

Hi everyone,

I have got my 10' Perfect Ten dish aligned fairly well now. I am tracking from 22w to 135w for c-band and ku-band (some ku issues on certain birds, but I'll probably get a 1.2m dish for ku anyway). I'm currently using a dual C/KU-band LNBF on the dish.

I am able to receive circular polarized signals such as those on 40.5w, 27.5w, 24.5w, and 22w, if I put the dielectric plate into the LNBF throat.

However, I would like to be able to add another C-band LNBF, or get some sort of setup so that I don't have to go out to the dish and insert/remove the dielectric plate every time I want to change from circular/linear or back again.

For starters I tried put a second LNBF offset from the first one using tie wraps. I attached a scalar to a second C-band LNBF, and then tried to simply place it offset of the current LNBF (above and to the left if facing the front of the dish). I used my SH-200 meter and moved the 2nd LNBF around until I found the best position. It seems to partially work, however I need to tune it more since I'm only getting the Left (Horizontal) signals, and it's definitely weaker. It is a pain to get it to tune, and in turn to tie it down with zip ties with the angles involved.

Also, I'm not really sure I should be placing it where I am. I have the dish pointed at 45w, and am trying to pick up 40.5w with the second LNBF. It seems that I need to put it higher and to the left, when facing the dish, but I would like confirmation of this from someone who knows.

I'll probably try to take two LNBF with scalar rings and do something similar to this next (only using LNBFs instead of the older-style feeds):

http://www.satelliteguys.us/threads/193463-C-band-Linear-Circular-Orthomode-Feed-Modification

Anyway, my question is, are there any other options for having reliable c-band linear and c-band circular on a single dish without having to manually insert/remove a dielectric plate? I don't know a lot about the older style feeds, but I'm wondering if there is any option for a feedhorn that would allow for both linear and circular (both H & V, of course)?

Thanks
sgs

I know that's not the answer to your question, but what type is the size and length of your Actuator?

 

[sgs]

I know that's not the answer to your question, but what type is the size and length of your Actuator?

It's a "Super PowerJack 36 inch QARL-3636" actuator, got it from drsat.ca.

I'm near Toronto (i.e. Eastern North America), but I've mounted the actuator on the left so that when it is fully retracted I can get the eastern satellites. I can probably get down to 8w, but there is some corn in the way, for now. I put the clamp that holds the actuator as close to the end of the actuator as possible, so that when fully retracted, the dish is pulled almost right down to point at the eastern horizon.

If I could weld in-place, I would weld a new longer tab (where the end of the actuator attaches and pushes/pulls) on to the existing mount. Then I could probably do the full arc to the west, as 137w and 139w isn't too much further. I don't like the extended actuator arm hitting the mount so I set the reed limits to where the actuator is essentially pushing all the way to be aligned "due south" without going further and slamming into the mount.

sgs