Signal Loss on C\KU Bands Setup

[Babadem]

I would get away from using diseqC switches and use a 4x4 multi switch. Something like this
http://www.amazon.com/Zinwell-SAM-4402-3A-DirecTV-Multi-Switch/dp/B000OUHRZW

Thanks.

 

[Babadem]

Your 4 port DiSEqC switch drawing looks fine to me and should work.
My suspect is the OpenBox receiver lnb voltage. The OpenBoxs have a little known problem with the lnb voltage regulator, not to be confused with the power supply. Can you substitute another receiver in your setup?
My OpenBox did this while it was still in warranty and was replaced. Now out of warranty it is starting up again after working fine all summer. I'm going to take it apart and fix it myself this time.
I will post the results and possible fix.
There are a few other threads in here with people having mysterious trouble with switches and signal dropping to zero that I suspect are all related to OpenBox lnb voltage.

Edit: Until more is known about this, as a precaution to all OpenBox owners, I would NOT connect ANYTHING to the loop thru. Voltage from the tagged on receiver can damage the OpenBox. Use a power pass splitter with diode protection instead.

I ran it into a variable power resistor for a few hours.
Set for horz. 19 volts held steady with the load drawing 420 ma. which is much above what my system draws and is near the max of the OpenBox.

I even put a 75 watt lamp over the open top and got it quite warm inside, still held steady.

Conclusion: none. Seems everything in the receiver is ok.

Last time I tested an OpenBox with this setup it sagged at a load of 210 ma and went to zero at 260 ma. Some receivers may have this problem my first OpenBox had.

Thanks, PixL for all the insights and suggestions.