GEOSATpro microHD and Standby Mode..LNB
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Tks. Brian..Just wanted to know this as to when I change out a lnbf I don't have to cut the power,just put it in standby mode would be adequate..on another note...how long does it take the lnbf to "warm up"after being on standby all nite..Thanks..
Depends on the LNB.
A perfectly operational and factory spec DRO type LNB may drift frequency up to +/- 3mhz as they heat-up. The amount of LO frequency drift depends on component quality, age, size, ambient temperature, etc.
Example: A blind scan with a cold LNB within factory specification of +/- 3mhz might yield transponder frequencies that could be up to a 6mhz difference than a blind scan with a hot unit.
PLL LNB types have minimal thermal drift. The GEOSATpro SL1PLL has a maximum drift of 300khz, but typically only have 50khz!
A perfectly operational and factory spec DRO type LNB may drift frequency up to +/- 3mhz as they heat-up. The amount of LO frequency drift depends on component quality, age, size, ambient temperature, etc.
Example: A blind scan with a cold LNB within factory specification of +/- 3mhz might yield transponder frequencies that could be up to a 6mhz difference than a blind scan with a hot unit.
PLL LNB types have minimal thermal drift. The GEOSATpro SL1PLL has a maximum drift of 300khz, but typically only have 50khz!
I suspect DRO frequency drift has less to do with "warm up" after applying power,
and a whole lot more to do with time of day.
Let's say: 3pm vs 3am.
and a whole lot more to do with time of day.
Let's say: 3pm vs 3am.
Don't understand the time reference. Are you referring to a lower nighttime ambient temperature? DRO frequency drift is mechanical and temperature related. The swing of 50 - 100+F is quite typical for most of North America.
An unpowered LNBF will be at ambient temperature and within a few minutes could be 115F +. Often have tested sample LNBFs running at 135F. Of course we quickly weed out the hot designs!
Yes, I was saying that self-heating was probably a smaller contributor than the difference between night time and day time temperature.
So anyone looking at power-on warm up drift was probably concerned with the wrong thing.
So anyone looking at power-on warm up drift was probably concerned with the wrong thing.
On a failing DRO the frequency drift is most evident during the self heating initial warm-up. During this warm-up, you could observe the LO shift 5+ mhz in the first few minutes of operation.
The extreme of an ambient temperature adds the additional frequency drift that users finally notice. A high or low outside temperature is the last straw which causes the LO drift to exceed their receiver's AFT circuitry range and the tuner can no longer lock the preprogrammed transponder.
The extreme of an ambient temperature adds the additional frequency drift that users finally notice. A high or low outside temperature is the last straw which causes the LO drift to exceed their receiver's AFT circuitry range and the tuner can no longer lock the preprogrammed transponder.
