Hi The GPS antennal goes into the TNC connector on the left hand side of the front panel. The box sources +5V power for an antenna.
Bob > On Nov 18, 2014, at 11:29 AM, Don Murray via time-nuts <[email protected]> > wrote: > > Hello all... > > Just getting up to speed on the KS-24361... > > My stupid question (s)... > > Where does the GPS antenna connect?? > > Does the GPS antenna port power the antenna? > > Need a replacement for my dead HP Z3816A... ;-( > > TIA... > > > > 73 > Don > W4WJ > > > > In a message dated 11/18/2014 3:26:52 A.M. Central Standard Time, > [email protected] writes: > > One of my Z3805's (with the double oven 10811 ocxo iirc) also performs > similarly at times to the 58503A mentioned by Said. From an adev > perspective > it's close to my BVA at some tau's (around a hundred seconds or so iirc.) > At times though the output seems to "jump" in frequency. My other Z3805 > from the same source doesn't work as well. > > None of the 10811's in my various pieces of test gear (some of which I > basically purchased to get the 10811's) worked all that well from an Adev > perspective. I used to buy HP5328 counters on the usual auction site with > 10811's and the 500MHz C channel for quite low prices. At least I still > have > a nice collection of frequency counters. > > > Sent from my iPad > > On 2014-11-17, at 1:23 PM, Said Jackson via time-nuts <[email protected]> > wrote: > >> Correct on all counts Bob. >> >> My two 58503A units from China are great for both ADEV and PN > measurements, better than anything else I have as a combo (I have Wenzel > ULNs for > even lower PN testing but they don't have any usable ADEV). I also have a > costly BVA and it can't compete against the HP unit. >> >> Those 10811s just rule. >> >> In fact my only complaint about the 58503A are the 60Hz related small > spurs you can see in the plots... >> >> Bye, >> Said >> >> Sent From iPhone >> >>> On Nov 17, 2014, at 12:28, Bob Camp <[email protected]> wrote: >>> >>> Hi >>> >>> The 58503 is a Z3801 with a pretty instrument style package put around > it - right? >>> >>> If so, it might / should have a 10811 in it rather than an MTI OCXO. > The 10811 is rated for -155 dbc at 100 Hz. That is much better than the > noise floor that the MTI’s seem to produce at 100 Hz. About the only other > GPSDO OCXO that gets to that level is the one in the original TBolts . There > you very much have to deal with spurs. That make the noise floor of limited > use in a practical system. >>> >>> Bob >>> >>>> On Nov 17, 2014, at 2:26 PM, [email protected] wrote: >>>> >>>> Hi Bob, >>>> >>>> yes, the 10MHz plot is rotten, no doubt. The 15MHz plot is quite good > till about 40Hz offset, then it becomes pretty rotten too. >>>> >>>> Here is one of my 58503A units (using the 10811 OCXO) as a > comparison.. measured against our DROR-IIA (this plot was actually done to > show the > DROR-IIA PN, but since that unit actually has less noise and spurs than the > 58503A we can simply use it as the reference for this purpose). >>>> >>>> The good news is that getting the close-in phase noise to be good is > very hard to do and the unit delivers that out-of-the box already. Filtering > out the noise and spurs above 40Hz offset is pretty easy to do. It should > be fairly straight forward to cobble up a small PN filter for those units > to get rid of the noise and spurs above 40Hz offset. >>>> >>>> bye, >>>> Said >>>> >>>> In a message dated 11/17/2014 09:31:46 Pacific Standard Time, > [email protected] writes: >>>> Hi >>>> >>>> Here’s the phase noise on the 15 MHz. There are a few spurs, and an > very real hump out at the likely frequency of the Lucent switcher. The 15 > MHz is pretty clean compared to most /all of the other units I’ve seen on > the > surplus market. >>>> >>>> I would not multiply this up to 40 GHz with a broadband multiplier. I > would be quite happy to run it into a PLL with a rational bandwidth. You > will beat the noise on the output with a fairly simple VHF VCXO past 100 Hz. > No reason to have a bandwidth outside the 20 to 80 Hz range. >>>> >>>> Math: >>>> >>>> 15 MHz to 150 MHz -> 20 log (N) -> 20 db. >>>> >>>> -140 dbc / Hz shown below at 100 Hz offset -> -120 dbc/Hz >>>> >>>> You can get numbers better than -120 dbc/Hz at 100 Hz offset out of a > number of pretty simple VHF VCXO circuits. Bert has one that seems to work > fine for him. >>>> >>>> Bob >>>> >>>> <DROR-IIA_Phase_Noise.png> >>> >> _______________________________________________ >> 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. >> > > _______________________________________________ > 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. > _______________________________________________ > 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. _______________________________________________ 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.
