Steve wrote: > Thanks for the info Bruce. > > I'm planning to use the Trimble Thunderbolt as the 10MHz source. > > The phase noise characteristics of that device are on the Trimble web > site. I'm not versed enough in the specifications to call it good, bad > or mediocre with respect to phase noise. Thoughts? > > Thanks. > > Steve K8JQ > > Steve
If one compares TvB's plot of the phase noise of a Thunderbolt with John Ackermann's plot of the phase noise of a TADD-1 at 10MHz. Then the phase noise floor of this particular Thunderbolt is lower than the phase noise floor of the TADD-1 at the particular gain used in John's test. Thus using the TADD-1 at this gain will degrade the noise floor of that particular Thunderbolt by about 7dB. However at 1Hz and 10Hz the phase noise of the Thunderbolt exceeds that of the TADD-1 by 15dB or more so the phase noise of that Thunderbolt will not be significantly degraded by the TADD-1 at those offset frequencies. Distribution amplifiers with lower noise floors and equivalent or better reverse isolation do exist but tend to be expensive. A design employing cascaded common base stages can have a significantly lower phase noise floor. Bruce _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
