Really good advice on what to checkout. 5370s are the devil to fix if somethings wrong such as jitter. Good luck. Paul
On Sun, Nov 14, 2010 at 12:40 PM, Bob Camp <[email protected]> wrote: > Hi > > Like a lot of stuff, the going price for these has dropped. They get less > and less respect every day ... > > One thing that may be specific to me - I do not consider a 5370A to be any > more or less valuable than a 5370B. They both do pretty much the same thing. > The 5370B might have fewer hours on it, it might not. On average 5370A > prices seem to run slightly higher than 5370B prices. Why is a mystery to > me. > > Bob > > > On Nov 14, 2010, at 11:57 AM, William H. Fite wrote: > > > Thanks, Bob > > > > He's asking $400 but I can tell by the look in his eye that he'll take > > substantially less. > > > > He's a lousy poker player, too... > > > > I asked him to turn it on about 0900 this morning and I'm going over in > an > > hour or so to check it out. > > > > Thanks again, > > > > Bill > > > > > > > > > > On Sun, Nov 14, 2010 at 11:44 AM, Bob Camp <[email protected]> wrote: > > > >> Hi > >> > >> Assuming: > >> > >> 1) All the knobs and switches are intact and working > >> 2) All the led's in the display work > >> 3) All the alarm and indicator LED's work > >> 4) The input amps are good > >> 5) All the connectors are intact > >> 6) The OCXO is good / on frequency > >> 7) It passes the diags > >> 8) Jitter is down below 100 ps ( should be below 40) > >> 9) You can check all this out before purchace. Let the beast warm up for > at > >> least an hour before you check it. > >> > >> Something in the $180 to $260 range is probably fair depending on > >> cosmetics. You might start out at $150 in order to compromise at $200. I > >> certainly would not pay over $300. I know the list sounds a bit long, > but > >> I've seen 5370's with problems in each of those areas. Pretty much > anything > >> damaged / non-functional would knock a pretty good chunk off the price. > >> > >> Bob > >> > >> > >> On Nov 14, 2010, at 11:29 AM, William H. Fite wrote: > >> > >>> Gentlemen, > >>> > >>> What is a reasonable price for a 5370A? Local guy here is trying to > hawk > >>> one to me. Not cosmetically perfect but fully operational. > >>> > >>> Yes, I know someone is going to say, "I got one for 50 bucks." But > >> really, > >>> what is a fair price? > >>> > >>> Thanks, > >>> > >>> Bill > >>> > >>> > >>> > >>> > >>> On Sun, Nov 14, 2010 at 10:48 AM, Magnus Danielson < > >>> [email protected]> wrote: > >>> > >>>> On 11/14/2010 09:41 AM, John Miles wrote: > >>>> > >>>>> > >>>>> I’ve looked at Wikipedia and I am as lost as when I started. > >>>>>> > >>>>>> Could someone walk me through the process step by step and also > >>>>>> tell me what test equipment is required? > >>>>>> > >>>>>> > >>>>> Besides the pointers at www.leapsecond.com , I've collected a few > >> links > >>>>> at http://www.ke5fx.com/stability.htm that may be helpful. > >>>>> > >>>>> The first .PDF link on that page is my presentation from the > Microwave > >>>>> Update conference a few weeks ago. It was meant as an introductory > >>>>> "Stability Measurement for Radio Nuts" talk, discussing the state of > >> the > >>>>> commercial art in light of what's available to hobbyists. > >>>>> > >>>>> The NIST links under "General timing and noise metrology", in > >> particular > >>>>> this one ( http://tf.nist.gov/general/pdf/2220.pdf ) are excellent. > >>>>> > >>>>> If you have an HP 5370A/B counter and a GPIB interface you can do a > lot > >> of > >>>>> good measurement work. With the appropriate software you can make > >>>>> conventional strip-chart style plots of frequency and phase, as well > as > >> ADEV > >>>>> and similar plots. Unless you are a software nut you probably do not > >> want > >>>>> to homebrew the necessary code to do this. Most people don't use the > >> same > >>>>> program for acquisition and plotting; a script or batch file does the > >> job of > >>>>> reading the data from the counter and spooling it to a text file, > while > >> a > >>>>> program like Stable32 or Ulrich Bangert's (search on df6jb plotter) > >> renders > >>>>> the graphics. > >>>>> > >>>>> My own app (TimeLab) is an exception, in that it attempts to do a > good > >> job > >>>>> at both data acquisition and rendering. It's still under heavy > >>>>> construction. Right now I'm rewriting all of the acquisition > routines > >> to > >>>>> support, among other things, the use of more than one GPIB counter at > >> once. > >>>>> > >>>>> Given that you have an HP 5370 available, if you wanted a > walkthrough, > >> you > >>>>> could try something along these lines: > >>>>> > >>>>> 1) Get an NI or Prologix GPIB adapter, install per manufacturer's > >>>>> guidelines. > >>>>> > >>>>> 2) Download the current TimeLab beta. You have two options here: > >>>>> http://www.ke5fx.com/timelab/setup.exe -- Graphically ugly but > >>>>> better tested > >>>>> http://www.ke5fx.com/timelab/setup_temp.exe -- Nicer looking, > >> but > >>>>> more likely to have bugs, and some features have yet to be ported > over > >> to > >>>>> the new codebase. Use this one for the instructions below. > >>>>> > >>>>> 3) Decide whether you want your HP 5370A/B to run in talk-only mode > or > >>>>> addressable mode and set its DIP switch accordingly. The software > will > >> work > >>>>> either way since it doesn't actually try to control the counter, but > >> for a > >>>>> 5370 I'd use addressable mode unless you have a reason not to. > >>>>> > >>>>> 4) Set up a basic frequency measurement to begin with. Feed a 10 MHz > >>>>> signal or whatever into the STOP jack, and hit FREQ and 1s. > >>>>> > >>>>> 5) In TimeLab, select Acquire->Acquire from HP 5370A/B, and then > select > >>>>> the NI interface or the Prologix interface's COM port from the list. > >> Hit > >>>>> the "Monitor" button and you should start seeing the counter's > >> frequency > >>>>> readings scroll by. If not, find out why before going any further. > >>>>> > >>>>> 6) Hit "Start Measurement." After a few readings have come in, you > >> should > >>>>> see your ADEV plot start to take shape. > >>>>> > >>>>> 7) Hit the 'f' key to switch to a frequency-difference chart, or the > >> 'p' > >>>>> key for a phase-difference chart. The 'y' key will toggle the Y-axis > >>>>> between easy-to-read round numbers and full display range. > >>>>> > >>>>> You can get somewhat cleaner measurements from the 5370 if you use > >>>>> time-interval mode rather than frequency mode, but time-interval > >>>>> measurements require a 1-pps or similar source and some additional > >> setup > >>>>> effort. > >>>>> > >>>> > >>>> 0) Essentially whatever source you have (crystal, Rubidium, Cesium, > >> GPSDO) > >>>> unless you haven't done it before, turn it on well in advance. I > prefer > >> days > >>>> over hours. Locked crystals such as Rubidium, Cesium and GPSDOs will > >> cancel > >>>> the last part of the oscillator drift but depending on details > >> performance > >>>> may be more or less compromised by this drift. I think this is one of > >> the > >>>> practical details one should not miss. > >>>> > >>>> I for one thinks that using a trigger signal such as the PPS or more > >>>> preferably a higher frequency trigger is worthwhile, as you get a more > >>>> stable rate of read-outs. Also, it gives a larger amount of raw data, > >>>> allowing for the increased degrees of freedom and quicker convergence > of > >>>> estimator(s). > >>>> > >>>> Do use TimeLab, I think it is a great way to get going. It's also fun > to > >>>> see the curve converge as more data comes in... > >>>> > >>>> Cheers, > >>>> Magnus > >>>> > >>>> > >>>> _______________________________________________ > >>>> 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. > > > _______________________________________________ > 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.
