Dual band Ku LNB and 22KHz...

[Externet]

Hi all. Your headache is back...

A receiving system with C band and Ku band on the same horn scenario, single coaxial, no extra control wiring....

12 V selecting vertical polarization; 18 V selecting horizontal polarization for both bands.
0 Hz selecting the C LNB; 22KHz selecting the Ku LNB
There is no diseqc implemented control at all, none of the LNBs are meant to react to it.

But: the Ku LNB has two bands: Low (10.7 to 11.7 GHz) enabled on 0 Hz; High (11.7 to 12.7 GHz) enabled on 22KHz.

Now the question:
If the receiver sends 22KHz; will the Ku be tuned to low or to high band ?

In other words, will the 22KHz pass trough the LNB selector and continue to the Ku LNB and pick high band or will not pass trough the selector and the Ku LNB will pick low band ?

Specifications tell the DC (and RF) passes fine on those selectors, but found no data on passing 22KHz. Do you know how they behave ?

[el bandido]

22KHz Is a Tone so it should pass through your system without issue. I do not know what kid of lnb selector you are using so you may want to share that information.

[Externet]

Thanks, bandido. The 22KHz switch is a simple Gecen SW 03/Q

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Cannot discern if 22KHz fed into the RX port will continue further out to any of the LNB inlet ports.

Edited: for this similar? schematic 13053

There is no path from the wrongly labeled "22KHz out" (should be RF out / 22KHz in) towards any of the LNB inputs. The tone is just amplified by V1; rectified by D1, D2 and switches V2 on or off to select input.

For another similar? schematic found, 13054

Appears to be a path from XS1 to either XS2 or XS3 depending on the value of L2, L3. Tone is amplified by VT1, rectified by VD3 and either VT2 or VT3 allow one input selected by VT4 or VT5.

[el bandido]

A 22KHz switch will work. Put the 5150 lnb on the 22KHz tone OFF side and the ku lnb on the 22KHz tone ON side. Then use 10600 for the ku lnb l.o.

Combination c/ku lnbs have done poorly on most dish systems. They seem to work best on dishes that re at least 3.5 meters in diameter.