[time-nuts] Efratom LPRO-101 Rubidium question....
Hello Time-Nutters-- I am working on building a downlinking AZ/EL tracking dish set up to receive the 8.2 GHz telemetry from the Suomi JPSS polar orbit meteorological/environmental satellite. The receiver seems to be working OK but it periodically appears to slowly drift frequency by 300 Hz to 400 Hz. I need some way to accurately determine what the actual RX receive frequency is. I have a vintage Efratom LPRO-101 Rubidium 10 MHz oscillator. I originally got it thinking that it would provide a decent phase-lock reference for my freq-counters, o-scopes, spectrum analyzers and Agilent/HP vector network analyzer. The only other item I have that has (or should have) a reasonably accurate 10 MHz reference output is a Trimble Thunderbolt. However, there is a several hundred Hz freq difference between the Efratom and the Trimble T-bolt. My question is how do I go confirming the frequency of the T-Bolt or the Efratom Rubidium? The Efratom has an adjustment pot to fine-tune its output frequency. How do Time-Nutters go about confirming the accuracy of frequency references such as my T-Bolt or Efratom rubidium oscillator? Thanks for any feedback / suggestions on this !! Off-list communications on this via my email is OK!! Mike Baker mp...@clanbaker.org Micanopy/Gainesville North Central Florida ** ___ time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-le...@lists.febo.com To unsubscribe, go to and follow the instructions there.
[time-nuts] Lady Heather v6 for Raspberry Pi......?
Hello, Time-Nutters-- One of several things keeping me off the streets and out of trouble these days is a home-brew system for downlinking and displaying imagery from the NOAA low-earth polar-orbit environmental satellites. A satellite tracking software package runs/controls the AZ and EL gear-motors that steer the 10-ft diameter dish. This dish beamwidth at 1700 MHz is only a couple of degrees. If the tracking program does not have pretty good time information the dish AZ & EL tracking is not close enough to provide a solid signal from horizon to horizon. The earth orbital periods of these NOAA birds is very close 100 minutes. Seems like they pop up over the horizon and disappear in just a couple of minutes. For AZ/EL tracking timing I use a Trimble T-Bolt with a Raspberry-Pi running Lady Heather v5 with Linux. The Lady Heather display runs 24/7/365 on a 12" monitor. A friend took pity on me and figured out how to get v5 Linux running on my Raspberry-Pi. Some months ago I saw a photo of a monitor screen running Lady Heather v6. I was particularly impressed with the new display features and improvements offered in v6. I keep hearing that Lady Heather v6 has been running successfully with Linux. However, I have not been able to find where to download a Linux version of Lady Heather v6 from! Creating/installing software is not one of my skills so I am hoping to find a source for downloading and running Lady Heather with Linux v6. Any info, thoughts, or feedback will be most welcome!! Mike Baker WA4HFR Gainesville/Micanopy N. Central Flori-DUH. mp...@clanbaker.org ___ time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-le...@lists.febo.com To unsubscribe, go to and follow the instructions there.
[time-nuts] Adjustment of Mean Well switching Power supplies
Time-nutters-- I was successful at getting 2 small Mean Well 15 V switching supplies adjusted down to 12 volts. On these particular models the output voltage pot was in series with a resistor which limited the output adjustment range. Swapping out the series resistor allowed trimming the output voltage down to 12.0 V. However, a different model Mean Well switching supply had no resistor in series with the adjustment pot and I was unable to figure out how to drop the output voltage down to anything lower than 14.2 VDC. Mike Baker WA4HFR Micanopy, FL * ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
[time-nuts] Interesting 1-60 MHz =/- 50 ppb Stratum-3 TCXO chip
Hello, time Nutters-- I have been phase locking the freq counters in my HP 6-GHz VNA, Tektronix spectrum analyzer and bench freq counter to the 10 MHz signal from a Trimble Thunderbolt via a 4-port distribution box and long coax cables to each of the instruments. This works well but is a pain in the tush connecting to long coax cables when the bench test gear are moved around. A friend suggested looking into some MEMS TCXO's made by SiTime to do this with. SiTime offers a wide variety of Stratum-3 TCXO chips. One of them is the SiT5358 which is spec'd at 0.05 ppm from 1 to 60 MHz. https://www.sitime.com/products/super-tcxos/sit5358 I am wondering what any feedback thoughts might be on this from the Time-Nuts gang? An eval-PCB board for the SiT5358 chip is available. What say the Time-Nutters gang about this approach for incorporating a small SiT5358 eval-PCB board into my bench test gear for phase locking to? I am also wondering which of the SuperStratum3 TCXO chips might be the best choice for a project like this? Any feedback on this is most welcome! Mike Baker Gainesville/Micanopy, Florida * ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
[time-nuts] Lady Heather V6.0...?
Hello, TimeNutters-- I first heard about 2 years ago that Mark Sims had developed a V6 beta version of Lady Heather and that it offered a number of new features. Presuming that by this time the new V6 would have been available I have searched for it but to no avail. Can anyone provide some info on the status of LH V6 ? I have kept Lady Heather V5 running on a 12" LCD monitor sitting on a shelf over my workshop workbench running 24/7/365. It always gets attention from folks that see it. Thanks to Mark Sims and any other Time-Nutters that have played a part in making Lady Heather available !! Mike Baker WA4HFR Gainesville/Micanopy, Fl USA ** ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
[time-nuts] Time-Nutters-- Adding Rubidium to a Thunderbolt...?
Hello, Time-Nutters-- Is it possible to add/combine/mate a rubidium osc to a Trimble Thunderbolt GPSDO? Have there been any examples of this that I could use as a guide? Thanks for any info/feedback on this!! Mike Baker Gainesville/Micanopy Florida USA *** ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
[time-nuts] Time-Nuts: Who was that person...?
Hello, Time-Nutters-- A month or so ago I posted a query on this list asking if anyone was interested in a collection of old (1950 - 1970) quartz crystals in evacuated glass tubes plus an assortment of crystals and crystal ovens from the same vintage. Two Time-Nut List members responded. I shipped one small box of assorted crystals and ovens to the interested person in Germany. However, I have lost my note of who the other interested Time-Nuts List member is. Would that person please email me with your shipping address and I will follow-through with my offer to ship to you in return for shipping costs ? I apologize for my carelessness in losing your shipping address!! Mike Baker WA4HFR Gainesville / Micanopy Florida USA mp...@clanbaker.org * ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
[time-nuts] Quartz crystals in a vacuum....
Time-Nutters-- I have an assortment of quartz crystals enclosed in sealed clear glass vacuum tube enclosures. If any list members are interested in having a couple of these for your collection of "interesting stuff" let me know and I will send them to you. Postage should only be a few dollars. H Biggest issue may finding suitable little boxes to ship them in. Mike Baker Micanopy/Gainesville, FL * ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
