Some transponders are strong, and others are weak. Is this intentional? Can a Customer save money by requesting a weak transponder?
Transponder Output Power Question
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Probably, since they use less battery power when they're in the dark. 
?If only distributing a signal to a few receivers, I imagine giant dishes and low power is lots cheaper.
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PS: the more uplink power you use, the stronger the signal from the satellite.
The satellite owner monitors all power levels.
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?If only distributing a signal to a few receivers, I imagine giant dishes and low power is lots cheaper.
.
PS: the more uplink power you use, the stronger the signal from the satellite.
The satellite owner monitors all power levels.
?
Most modern satellites output: C-band 35 - 100watts and KU-band 20 - 130watts (DBS 250+ watts). The beam shaping also affects the required output power to provide required EIRP levels at the downlink locations.
Possibly over simplified.... Less popular satellites / lower wattage / less power consumption = decreased demand on the finite satellite resources = lower uplink $$$
One of the cost factors when an uplinker or satellite management is preparing the link budget for a broadcaster is the amount of power to provide the required signal and reliability in a given footprint. The amount of amplification required on the satellite platform to meet the link budget will be affected by the uplink dish size and output. One broadcaster may uplink with a low gain dish and power for direct to home and require 85% uptime using a 90cm dish with average to poor performance characteristics. Another broadcaster may be distributing to commercial downlinks with 4 meter dishes with defined performance and require 98% uptime and another to 7 meter dishes with exceptional performance and 90% uptime.
Each link budget purchases the bandwidth and the signal gain and robustness needed to meet their distribution requirements.
Possibly over simplified.... Less popular satellites / lower wattage / less power consumption = decreased demand on the finite satellite resources = lower uplink $$$
One of the cost factors when an uplinker or satellite management is preparing the link budget for a broadcaster is the amount of power to provide the required signal and reliability in a given footprint. The amount of amplification required on the satellite platform to meet the link budget will be affected by the uplink dish size and output. One broadcaster may uplink with a low gain dish and power for direct to home and require 85% uptime using a 90cm dish with average to poor performance characteristics. Another broadcaster may be distributing to commercial downlinks with 4 meter dishes with defined performance and require 98% uptime and another to 7 meter dishes with exceptional performance and 90% uptime.
Each link budget purchases the bandwidth and the signal gain and robustness needed to meet their distribution requirements.
And the signal strength in your area, as reported at Lyngsat, to best of my knowledge is that is if the transponder is 'lit up' to maximum power level. May be the same for satbeams. . Many of the services renting satellite bandwidth have dishes quite a bit larger than ours. Meaning they can receive a much weaker signal than our hobbyist systems. Some times, reliable service can be had with smaller, so be aware, take their minimum dish size as only a recommendation-YMMV. Another part of the hobby - Seeing what will work, to some performance standard, and what doesn't.
Think the highest power on the newer satellites approaches 35 watts. Some to 50. BITD, there was not much above 10W, total transponder power. But that's if the transponder is 'fully loaded'. (SR's of +~300000 or a 36mhz wide analog) lower SR's only uses a portion of the total bandwidth available. Using power theory, if a 50W transponder is 'fully loaded' with two equal SR streams occupying the whole transponder, each could use theoretically, half of the total available. 25W each. But even if there's only one stream occupying half the bandwidth available, doesn't necessarily mean that it IS using half the power. It's usually less than half the power. Depends on their 'link budget', what they require, which depends on their desired 'up time' and their receive dish sizes. How much power they require, and the bandwidth used, determines what the satellite rental will cost. In some rare instances, they could be using all the available power in only half the bandwidth of a transponder. But think that scenario would be avoided whenever possible. As the unused bandwidth is not available for others. as there's no power available.
Hope that wasn't too confusing, I almost confused myself.
Think over the 'pond' the total transponder power may be much higher, reading Remlaps results, on his miniBUD.
Think the highest power on the newer satellites approaches 35 watts. Some to 50. BITD, there was not much above 10W, total transponder power. But that's if the transponder is 'fully loaded'. (SR's of +~300000 or a 36mhz wide analog) lower SR's only uses a portion of the total bandwidth available. Using power theory, if a 50W transponder is 'fully loaded' with two equal SR streams occupying the whole transponder, each could use theoretically, half of the total available. 25W each. But even if there's only one stream occupying half the bandwidth available, doesn't necessarily mean that it IS using half the power. It's usually less than half the power. Depends on their 'link budget', what they require, which depends on their desired 'up time' and their receive dish sizes. How much power they require, and the bandwidth used, determines what the satellite rental will cost. In some rare instances, they could be using all the available power in only half the bandwidth of a transponder. But think that scenario would be avoided whenever possible. As the unused bandwidth is not available for others. as there's no power available.
Hope that wasn't too confusing, I almost confused myself.
Think over the 'pond' the total transponder power may be much higher, reading Remlaps results, on his miniBUD.
A little off-topic, I mean, way off topic -- in outer space -- the 70 meter dishes of NASA's Deep Space Network can transmit at up to 400 kilowatts of power. Can't have no stinkin' rain fade when talking to Mars.
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