Eugene, Welcome to the list and beware of how 'addicting' this can be. I started out with your exact same purpose, minus all the equipment you have, and am still a 'newbie'.
First question is do you want a 'primary' standard (in essence, one that does not need to be calibrated) or a secondary standard? The two practical choices for a primary standard are a GPSDO and a Cesium Beam Standard. For a secondary standard, Rubidium based oscillators or a good OCXO would seem the most practical. The Thunderbolt is a good choice and I do not know if the OCXO in the unit will make a big difference for your purposes. It does require +12 VDC, -12 VDC, and +5 VDC though. I am not a big fan of switching power supplies for this application. The Z3805A requires only a single power supply and the Z3816A (at least) had an option for 110 VAC. It tracks 8 sats. A single DC supply is likely the easiest to build a battery back up for for continuous operation. You can 'discipline' with a single sat once the site survey is complete and, again, the number of sats is not likely to be an issue for your purposes. You may have already found it but you might want to take a look at http://www.realhamradio.com/ for additional information about the various Z38xxA units. Beware the shipping fees from Yixun. And, finally, how will you know when your 'reference' fails? You will probably want to get at least one, if not two, additional units so you can leave one running and have another you can bring on line in relatively short order just to compare. Hope this helps. Joe -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of W2HX Sent: Thursday, November 25, 2010 10:48 PM To: [email protected] Subject: [Bulk] [time-nuts] ok, newbie questions Hi all, I am sure my questions have been asked before. Unfortunately, the mailman style archives are so hard to search through. So forgive me my transgressions. Happy will I be to get a reference to an old thread that answers my questions. Don't need new answers if old ones suffice. (of course new answers always welcome!) I am looking for a 10 MHz standard for my lab. Accuracy/stability probably wouldn't make a hill of beans difference in the stuff I do, so my questions are more academic and it's just nice knowing I have a "really good" standard. 1. So from reading about this topic on KE5FX.com I understand that a better ocxo makes for better phase noise and near-term quality. I also understand that some later tbolts had a very good ocxo in them and therefore would not benefit significantly from an upgrade as ke5fx did using an HP 10811 unit. I am considering a thunderbolt advertised on ebay by "flyingbest." I will be traveling to China (mainland, and Hong Kong) on business the last two weeks in December so I might save some shipping. Here is a photo. Can anyone tell me if this unit has a "better" 10811-class ocxo or "not so good "ocxo? I also understand that not all ocxo's are created equal, even if they are the same model number. http://tinyurl.com/2dg2dz3 2. Other GPS DO units seem to differ on the number of satellites they can receive from simultaneously (channels). What is the net effect of having a standard that can see 6,8 or 16 birds? Is noise averaged out? Is stability/phase noise improved? Here is an example of a 16 sat unit. Anyone have any experience with this unit? Good/bad indifferent? It seems they can be had for about $200. http://tinyurl.com/2ad5kls 3. And then there is the venerable HP units like this one. I understand this uses the 10811 ocxo. Other than the better ocxo, is there anything inherently superior about these HP units to warrant the additional cost? Or are we mostly just paying for the HP name? This one is 6 sats. http://tinyurl.com/24tkwdv Lastly, my use of a 10 MHz standard will be for use in equipment like microwave counters (EIP 548A), Spectrum analyzers (HP 8658B) VNA's (HP 3577A, 8753C to 6 GHz), synthesizer (HP 3326A and HP 8662A), premium receivers (Harris 590H), etc., etc. For these purposes, is a GPS DO advised, or perhaps a rubidium standard? For example, I don't need this to power a clock. Just a good, clean, stable signal with low noise, low spurs, etc. What's the overall opinion? THANKS !!!! (here's to hoping this message looks better than the first two tests I made) 73 Eugene W2HX _______________________________________________ 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.
