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<blockquote data-quote="a33" data-source="post: 1025113" data-attributes="member: 332642">How my diode-solution would work:The 22kHz is superimposed on the DC voltage with an amplitude of x (0.6 volt or so? don't now the value by heart).When with MS1 the lowest voltage of this amplitude is lower than the highest voltage of MS2, interference occurs.So what you want is that the highest voltage of MS2 is lower than the lowest voltage of MS1; using diodes. Then no interference can occur.Of course the voltage must still be enough to power the LNB. That you can assess yourself.My relay-solution would keep power from MS2 cut-off (by the relay), while power of MS1 is on. You only have to have a separate signal-path (DC-blocked) for the MS2, while MS1 is on.But though it could work, I'm no fan of 'hard' switches.However I thought of a third way, which I would also prefer (next to the diode-solution):While your LNB just needs power and no 22kHz, why not use a separate external power supply and a 'power inserter'? No need for any 0/22kHz switches then. In the signal path you can split whatever you want (using DC-blocked splitters).When you're not familiar with a power inserter: A power inserter has a coil to pass the power while diminishing the passing of RF-signals in the 'power' path, and a capacitor in the RF-path. greetz,A33</blockquote>

[QUOTE="a33, post: 1025113, member: 332642"] How my diode-solution would work: The 22kHz is superimposed on the DC voltage with an amplitude of x (0.6 volt or so? don't now the value by heart). When with MS1 the lowest voltage of this amplitude is lower than the highest voltage of MS2, interference occurs. So what you want is that the [B]highest[/B] voltage of MS2 is [B]lower[/B] than the[B] lowest[/B] voltage of MS1; using diodes. Then no interference can occur. Of course the voltage must still be enough to power the LNB. That you can assess yourself. My relay-solution would keep power from MS2 cut-off (by the relay), while power of MS1 is on. You only have to have a separate signal-path (DC-blocked) for the MS2, while MS1 is on. But though it could work, I'm no fan of 'hard' switches. However I thought of a third way, which I would also prefer (next to the diode-solution): While your LNB just needs power and no 22kHz, why not use a separate external power supply and a 'power inserter'? No need for any 0/22kHz switches then. In the signal path you can split whatever you want (using DC-blocked splitters). When you're not familiar with a power inserter: A [B]power inserter[/B] has a coil to pass the power while diminishing the passing of RF-signals in the 'power' path, and a capacitor in the RF-path. greetz, A33 [/QUOTE]

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