DMX-741 setup question

[Cham]

Just a quick question for those with the DMX741 lnbf feedhorns;
Can you set up the receiver to pick up both C and Ku signals without switching sats? I am thinking using the "Universal" setting and using 10750 and 5150 LO settings and the receiver automatically switches the 22KHz, just like a universal Ku LNBF? Just wonder if anyone has done that.
(This is not the DMX741U)
-C.

 

[SatelliteAV]

Universal type LNBF selection between C-band and KU-band is probably not possible as most receivers use a specific frequency range when Universal type is selected and assign a switching frequency (11.7GHz) within that range to switch between high and low LO Frequencies. C-band and KU-band LNBs output in the same IF frequency range.

Remember, the LO Frequency setting only changes the calculation frequency for the user interface display.

 

[Cham]

Hi Brian,
I think I can input the LO frequencies on the Pansat when set to "universal" to get the frequencies to read correctly... Don't have the receiver here though to experiment... The fact that this LNBF uses 22KHz switching makes me think it's possible but would have to actually install one of these feeds to play with. Don't see one in your eBay Specials!

Guess all this would do is streamline the satellite setup a bit when programming a receiver. The AzBox ultra came with pre-programmed C and Ku transponder frequencies on the same satellites... guess that got me thinking.
Tnx..
-C.

 

[SatelliteAV]

I agree with you that it is possible if the receiver's high and low LO Frequencies are a user setting.

 

[Auric]

Interesting Cham.
My old Coolsat is not that way (which is my main receiver), but I have another receiver that is...I never thought of trying that. I might give it a shot :up

 

[Cham]

Well I had to order a DMX741 just to try it. Arrived a few days ago so I had to install it and play today.

I am surprised the C-band signals are about the same as the DMX242 I replaced. Ku signals are a wee bit lower than the 1.2m F* and Universal LNBF. The 741 fit right into the 242 scaler ring, likely the same part for either lnbf. This is using an 8' spun aluminum shallow dish with high focal depth.

I was surprised though however when I went to set up the receiver as I was hoping to so with C and Ku on one satellite in the Pansat's satellite list. Couldn't input the 5150 and 10750 local oscillator frequencies... they are hard programmed for the various universal Ku lnbf setups.. at least in the firmware currently installed in the 3500. I was sure you could set them independently. Maybe the factory firmware allows this, I don't have factory firmware loaded at the moment.

Auric, maybe you will have better luck with your other receiver!

-C.

 

[Auric]

Well I had to order a DMX741 just to try it. Arrived a few days ago so I had to install it and play today.

I am surprised the C-band signals are about the same as the DMX242 I replaced. Ku signals are a wee bit lower than the 1.2m F* and Universal LNBF. The 741 fit right into the 242 scaler ring, likely the same part for either lnbf. This is using an 8' spun aluminum shallow dish with high focal depth.

I was surprised though however when I went to set up the receiver as I was hoping to so with C and Ku on one satellite in the Pansat's satellite list. Couldn't input the 5150 and 10750 local oscillator frequencies... they are hard programmed for the various universal Ku lnbf setups.. at least in the firmware currently installed in the 3500. I was sure you could set them independently. Maybe the factory firmware allows this, I don't have factory firmware loaded at the moment.

Auric, maybe you will have better luck with your other receiver!

-C.

Mine is an old Coolsat 6000
What I did was create my own sat list. All satellites with C & Ku transponders (like SES1 for instance) I have two positions.
SES 1 C ( I set LNB to low 5150 port 1)
SES 1 Ku (I set LNB 22KHz "on" 10750 Port 2)

All my C band is port 1
All my Ku is 22KHz "on" port 2

So in a sense my receiver sees them as two different Sat's

 

[stanleyjohn]

I do the same as Auric!You could just keep switching between c and ku on one sat listing but that is a pain.