Hi Does the Abricon have an EFC input? If so, rigging up a PLL to lock 122.88 to 10 MHz is probably the best option.
Bob > On Apr 3, 2022, at 7:57 PM, Jeff Blaine <[email protected]> wrote: > > I've got a couple of Red Pitaya 122-16 SDR and want to discipline them to an > external low noise GPSDO source. Wanted to see if there were some easy > solutions that fell into this category. > > For the prior generation (QS1R), I had built a homebrew OCXO based on a > custom low noise crystal from ICM and that worked great for the 125 Mhz > application. Unfortunately this Pitaya is a bit removed in Fc and ICM has > been out of biz for several years now. > > The RP's on-board oscillator is the respectable Abracon ABLNO 122.88 which > runs about -115 dBc/hz at 100 Hz spacing and that's probably not a limitation > for the unit. Unfortunately the OSC is a bit too sensitive to external temp > and wanders around quite a lot (+/- 5 PPM) compared to the homebrew OCXO - > over the annual ambient temp range of (10-35C) (all datasheet referenced > values). The Abracon unit is mounted on the board with the FPGA and sees > additional temp range depending on other heat generation factors (FPGA > loading). > > I have a couple of commercial GPSDO on the bench now, so a pretty clean 10 > Mhz GPSDO reference is available now. And I've seen enough board discussion > to know that a homebrew GPSDO solution is one of those "it's harder than it > looks" things. Hence the desire just to buy whatever is the silver bullet, > as long as it does not require too much silver. ha ha > > Appreciate any suggestions. TKs! > > 73/jeff/ac0c > alpha-charlie-zero-charlie > www.ac0c.com > > _______________________________________________ > time-nuts mailing list -- [email protected] -- To unsubscribe send an > email to [email protected] > To unsubscribe, go to and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] -- To unsubscribe send an email to [email protected] To unsubscribe, go to and follow the instructions there.
