Imho phase noise is probably as important as long term stability in this application.
On Fri May 27th, 2011 10:51 AM EDT David Kirkby wrote: >On 27 May 2011 15:21, Bob Camp <li...@rtty.us> wrote: >> Hi >> >> You also may want to avoid an oscillator with much 10 MHz content in it. All >> sorts of odd things can happen with spurs when you have unplanned stuff on >> the main reference. Another thing to look closely at is - how much of the >> radio tracks the reference? On some radios, they don't really lock >> everything up. You get better performance, but not quite what you would >> expect. >> >> Bob > >Yes, a band-pass filter would seem sensible here. > >To the best of my knowledge, everything is locked to this 20 MHz, so >there should be a significant improvement. > >However, I must admit as to wondering whether its worth the bother. I >have a Yaesu FT-ONE, which is a pretty poor design, despite it was the >top of the line Yaesu transceiver in its day (~1982) costing $3000. It >has a synthesizer for 100 Hz steps and then uses a varicap diode to >get the 10 Hz steps! This is not very stable, but in practice is >stable enough. There's nothing much one can do about that - perhaps >keeping the temperature constant in the vicinity of the varicap and >other critical components would help. But it also suffers from the use >of more than one reference, so hard to really stabilise. > >The Kenwood TS-940SAT should be a lot more stable anyway. The Kenwood >actually seems a lot better technically to me, despite it costs only >$2000 and was released about the same time as the Yause FT-ONE. The >Kenwood TS-940S has a built in ATU (not even an option on the Yaesu >FT-ONE), FM (optional on the Yaesu FT-ONE), TCXO (not even optional on >the Yaesu). > > >I might however look at using a TCXO o OCXO in the Kenwood. > >Dave > >_______________________________________________ >time-nuts mailing list -- time-nuts@febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
