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Jan 5th, 2011 at 9:25am
I would recommend avoiding having anything set to either its minimum or maximum.
Reasons (not in any particular order):
It limits the direction of any future possible in-service adjustments.
It increases the possiblility of high noise-floor or overload problems.
Setting anything to minimum value increases the risk of an accidental 10, 20, 30 or 40 dB increase.
Equipment works better in the middle of its design range (less noise, better linearity, less intermodulation).
If you have a high power amplifier operating at very low power output be very careful not to accidentally increase the input. Consider putting a fixed attenuator on the input to the HPA.
If you have a combining network on the transmit side, so as to allow multiple transmit modems, then terminate all unused inputs with 50 or 75 ohm terminations.
If any manufacturers are reading this, note my suggestion that typed-in or keyed-in power output or attenuator settings should only be changeable upwards in small 1 or 2 dB steps. It should not be possible in the firmware to increase modem output levels in large steps.
Useful reference: Satellite Users Interference Reduction Group
Best regards, Eric.
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