From: Bruce Griffiths <bruce.griffiths@xtra.co.nz> Subject: Re: [time-nuts] Advice on 10 MHz isolation/distribution Its easy to calculate a lower bound to the amplifier phase noise floor from the signal level at the output and the amplifier output noise due to feedback resistors together with the amplifier input voltage and current noise. The actual phase noise floor  may be a few dB higher. Bruce Yes, it is easy to calculate. Clay

life speed wrote: > From: Bruce Griffiths<bruce.griffiths@xtra.co.nz> > Subject: Re: [time-nuts] Advice on 10 MHz isolation/distribution > > Its easy to calculate a lower bound to the amplifier phase noise floor > from the signal level at the output and the amplifier output noise due > to feedback resistors together with the amplifier input voltage and > current noise. > The actual phase noise floor may be a few dB higher. > > Bruce > > Yes, it is easy to calculate. > > Clay > > The calculation is useful to help eliminate amplifiers that will not meet the phase noise floor specs. The amplifiers that remain will then need to be tested/measured for their actual phase noise. Bruce