Thanks Jack, I wonder specifically which parts are included with the new SRL+Xv8.3 kits then...
David --- In [email protected], Jack Brindle <[EMAIL PROTECTED]> wrote: > > David; > > Take a good look at the Si570 data sheet. The device is offered in > several bin-outs as far as parameters are concerned. Both CMOS and > LVDS parts are offered in 20ppm versions. It appears to me that the > most significant difference between the two parts is the maximum > frequency that can be generated. The LVDS part, being designed for > very high-speed optical fiber operation can run at much higher > frequencies, and its LVDS outputs can drive much farther distances. > > I doubt it makes much difference as to which is used, although the > LVDS part could conceivably be used at 6 or 2 meters (or higher) if > you wish to experiment. > > > On May 3, 2008, at 9:37 PM, drmail377 wrote: > > > On the Si570 Group Buy page at: > > > > http://www.softrockradio.org/ > > > > The specs there imply the LVDS version of the Si570 has 20ppm > > stability vs. 50ppm for the CMOS Si570. This is a significant > > advantage to the LVDS part in my opinion. > > > > There are some studies of phase noise by Mike Collins KF4BQ in the > > Files area. If my whiskey-soaked memory serves, the LVDS Si570 does > > outperform the CMOS version in the tests, but it is arguable the > > differences will be noticeable on HF in my opinion. > > > > Given the LVDS part is only $2 more than the CMOS part, and it is > > cleaner and significantly more stable. One would wonder why the CMOS > > part would ever be used with a SRLite. Comments? > > > > 73's David > > > > --- In [email protected], k5nwa <k5nwa@> wrote: > >> > >> At 01:42 PM 5/3/2008, you wrote: > >> > >>> So what is the advantage of the LVDS part over the CMOS one? > >>> According to the spec, max current drain is not much different, but > >>> the LVDS part supports much higher frequency output. Does it also > >>> have a cleaner output? > >>> > >>> On May 3, 2008, at 11:17 AM, k5nwa wrote: > >> > >> You got it, the LVDS has a much higher frequency range and it's > >> output is cleaner by a bit, but it appears from reports that the CMOS > >> version is clean enough for most peoples usage. > >> > >> A LVDS signal can be also sent a fair distance over twisted pair > >> wiring without degrading, CMOS does not have such an option. On my > >> initial test the LVDS chip was connected to the SoftRock with a 3' > >> CAT5e unshielded twisted cable pair and the signal was clean, it > >> worked fine with a 10' cable also. > >> > >> > >> Cecil > >> K5NWA > >> www.softrockradio.org www.qrpradio.com > >> > >> "Blessed are the cracked, for they shall let in the light." > >> > > > > > > > > ------------------------------------ > > > > Yahoo! Groups Links > > > > > > > > - Jack Brindle, W6FB > ------------------------------------------------------------------------ > --------------------- >
