[time-nuts] GPS Antenna Grounding/Lightning protection. [Cone of protection and other opinion]

The "Cone of Protection" is a thumbrule.  It's not a myth, but it's also not an absolute law of nature. It's a self-fulfilling prophecy to some degree because it drives component design guidelines.  Bunker spacing is also a thumbrule, based on a lot of horrible experience. It's also a function of

Re: [time-nuts] Low phase noise affordable GPSDO

The PN of the output amplifier in the thunderbolt will limit the PN nois of the 10Mhz output to a value significantly higher than the actual PN at the output of a low PN OCXO. Bruce > On 21 June 2018 at 09:26 Attila Kinali wrote: > > > On Wed, 20 Jun 2018 14:27:35 + > Ethan Waldo

Re: [time-nuts] Trimble 57963-80-DA1 assembly.. request for schematic

Hello Ignacio! Perhaps your unit acts in a similar way to mine : I apply power [13.6V], and immediately the leftmost "power" LED is solid "on". The red "1 PPS" led stays "on" for a second or so, does a double flash , and then flashes at 1PPS - Even if the ovens are not up to temperature. I thought

Re: [time-nuts] Trimble 57963-80-DA1 assembly.. request for schematic

Hi, On the 57963-D (57964-80 in firmware) that I have, the power up sequence after being off a short time is: Both LEDs red for 3 seconds, briefly blink other colours, then the ALM LED goes off and the ACT one goes solid green. It starts tracking GPS during this period. At 2m, the ACT LED starts

Re: [time-nuts] Low phase noise affordable GPSDO

Hi > On Jun 20, 2018, at 10:27 AM, Ethan Waldo wrote: > > Hello time afficionados. I've tried my best to scan through the archives to > see if this has already been answered, so apologies if I missed something > relevant. I am going to be experimenting with >10Ghz microwave frequency >

Re: [time-nuts] Low phase noise affordable GPSDO

On Wed, 20 Jun 2018 14:27:35 + Ethan Waldo wrote: > I've tried my best to scan through the archives to see if this has already > been answered, so apologies if I missed something relevant. I am going to > be experimenting with >10Ghz microwave frequency grounded coplanar waveguide > phase

[time-nuts] Low phase noise affordable GPSDO

Hello time afficionados. I've tried my best to scan through the archives to see if this has already been answered, so apologies if I missed something relevant. I am going to be experimenting with >10Ghz microwave frequency grounded coplanar waveguide phase combining/cancellation/detection

[time-nuts] HP cesium beam tube life

The "shelf life" referred to is only related to tube vacuum without pumping occasionally. It was derived from an estimate of how badly a worst case tube would leak. Most tubes have an almost perfect vacuum seal and this "shelf life" is indefinite. Leaving a 5061A/B on and in the Cs-off mode

Re: [time-nuts] Trimble 57963-80-DA1 assembly.. request for schematic

Hi Don, While I don't have this model, I had a problem  with my Nortel-Trimble NTGS50AA with similar symptoms. This was caused by the way the interconnection between the two PC boards, they use a flat cable with unkeyed connectors on it so they could be reversed. Using one of the the

[time-nuts] Trimble 57963-80-DA1 assembly.. request for schematic

Hi, I just received one ex-China GPSDO`s which uses the assembly mentioned above. It is nicely built, but has a design problem with the ACT [activity], and ALM [alarm] LED`s on the ancilliary pcb not following the LED`s on the Trimble pcb - they don`t activate properly. Would one who knows please