Hi Magnus: I goofed, it's actually 5.12 MHz, the driving crystal standard for the ICOM 260A 2 meter transceiver synthesizer. I want to use it with a transverter for moonbounce, hence would like to start out with a solid reference frequency. Might even be overkill. See, I knew it could be done with (almost) some 7400's :-) Thanks for the hint! The thing to do then is to pick off some of the existing xtal frequency, and as you say count to the common denominator. A little varicap in the crystal circuit can then be driven by the phase comparator... Should not be too hard to do... Don
Magnus Danielson > Don, > > On 07/02/2011 09:48 PM, Don Latham wrote: >> Hi Anders: >> >> I need something to give 2.048 MHz from a 10 MHz source, and have not >> too aggressively tried to find a way; have followed with interest many >> suggestions from TN's. I found a company called Vectron that makes, >> ostensibly, very nice frequency translators, with an fin and an fout, >> with reasonable phase noise characteristics (?), the data sheets are >> available and intriguing, but I spent an hour or more trying to find a >> way to actually buy one. > > Getting 10 MHz to 2,048 MHz isn't all that hard. You can do it in good > old 4000 CMOS series if you need to. What application to you need it > for? I recognice it as a standard telecom frequency and well have in > fact implemented 10 MHz to 2,048 MHz conversion (even if that was not > the primary target). The wideband noise needs isn't very daunting in > telecom applications, but long-term stability is another thing. > > If you really do not need to have very good wideband phase-noise, a 4046 > and a few dividers will help you. > > 10 MHz and 2,048 MHz has the highest common frequency in 16 kHz, so you > need to divide by 625 on the 10 MHz and 128 on the 2,048 MHz. If you > settle with the 4046 oscillator or chooses an off the shelf VCXO depends > on what you need, but it is not too hard and too expensive to come by. > > Cheers, > Magnus > > _______________________________________________ > 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. > -- "Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind." R. Bacon "If you don't know what it is, don't poke it." Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.com _______________________________________________ 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.