It is more of a counter-assisted drift stabilizer than a true phase lock as would happen if locking a 10811 to an external standard. Rob, NC0B
Sent from my iPad > On Jan 11, 2016, at 1:00 PM, "bownes" <[email protected]> wrote: > > > > > The 8640 will lock to an external 5Mhz reference. That's what the BNC in the > heatsink is for. At least that is where it is on mine. > > The trick is doing a good divide by two. > > However, that said, the 8640 tops out at ~1024MHz, which if you get > interested in even the lower microwaves, is not quite enough. > > > > Bob > KI2L > >> On Jan 11, 2016, at 09:47, Rob Sherwood. <[email protected]> wrote: >> >> The HP 8647A may be the worst signal generator HP ever made. The 8656B >> won't even go down low enough in level to make a noise floor measurement on >> a modern transceiver. Sure you can add external attenuation, but you won't >> know about how much leakage is occurring. Otherwise why wouldn't HP have >> added another 15 dB attenuation in the box? That is why I mentioned the >> 8657B. Yes the 8662A's reliability issue is the power supply. No question >> not a starter generator. The 8642A was never intended for field repair, but >> it is the only generator with low enough phase noise to test top radios >> today, and something a ham could afford. Again, not the first sig gen that >> should be on your list >> >> Rob, NC0B >> Sent from my iPad >> >>> On Jan 11, 2016, at 8:01 AM, "Nathan Johnson" <[email protected]> wrote: >>> >>> >>> >>> I really appreciate all the help. I really like that Ref0 combination, I >>> don't >>> see any Ref1s available right now, but you are saying that any decent >>> GPS+Arduino can substitute? Should I be looking in the archives for that, >>> or is >>> there a website? >>> Minor clarification to my earlier post about the signal gen, I am aware >>> that the >>> 8640 won't lock to an external reference. I had intended that to read >>> 8640-something or 50-something. I'm watching an 8647 and an 8656b on the >>> usual >>> site at the moment. That 8662 looks beautiful, but it's a huge investment >>> for a >>> piece of old gear that has a reputation for being a bit... Cranky and >>> opinionated. I have no practical need for that now, so I won't sign up for >>> that >>> kind of challenge until I do. >>> I'm quite familiar with how this stuff multiplies, I have a Tektronix scope >>> collection, and have been a lurker on the TekScopes list for about a year. >>> There >>> is a running joke on that list about "scope acquisition disorder". I'm >>> pretty >>> sure that I'm infected, but I only have 5 scopes in the house at the >>> moment, so >>> it's not that bad... Yet! >>> >>> Nathan KK4REY >>> Sent using CloudMagic Email >>> [https://cloudmagic.com/k/d/mailapp?ct=pi&cv=7.4.15&pv=9.1&source=email_footer_2] >>> On Mon, Jan 11, 2016 at 04:28, Discussion of precise time and frequency >>> measurement <[email protected]> wrote: >>> Good thread everyone. >>> Nathan you have received a lot of wisdom and humor today. >>> Yes for sub $200 you can be in good shape. >>> If lucent remember a Ref0 needs an arduino and a good GPS 1 PPS. >>> Though frankly even neo6s play well. >>> If a Ref1 it has a GPS in and no need for the arduino. The $175 gets you a >>> ref1 and ref0 combo that tie together usually with a cable thats shipped >>> with the units. >>> Mine were brand spanking new. NOS. >>> Good luck. >>> To Ron ohhhh yes no shed or anything but the gear builds up. Darn thing is >>> this stuff actually last longer then an iPhone99X due out tomorrow I am >>> sure. >>> Paul >>> WB8TSL >>> >>>> On Sun, Jan 10, 2016 at 4:31 PM, Rob Sherwood. <[email protected]> wrote: >>>> >>>> Paul, >>>> >>>> Your last paragraph was a hoot. A ham friend of mine recently rented a >>>> storage shed to keep all his spare test equipment and parts units. Another >>>> ham friend used to have four storage units to store all his "stuff". The >>>> disease is not curable with either time or antibiotics. >>>> >>>> My XYL will have to deal with two homes with labs and ham shacks, 7 >>>> towers, 13 yagis, etc. when I am SK. Need I say more. >>>> >>>> Rob >>>> NC0B >>>> >>>> -----Original Message----- >>>> From: time-nuts [mailto:[email protected]] On Behalf Of paul swed >>>> Sent: Sunday, January 10, 2016 1:56 PM >>>> To: Discussion of precise time and frequency measurement >>>> Subject: Re: [time-nuts] New Member + Basic Questions >>>> >>>> >>>> >>>> Nathan, >>>> Bob shared a link for the Lucent units and a great amount of detail has >>>> been shared on Time-nuts about them. They will do what you want. The Ref0 >>>> requires a external GPS receiver and another Time-Nuts Arduino. It works >>>> really well and the quality of the ref0 seems to be that of the 1pps >>>> feeding it. >>>> But they also make a no brainer pair that has a ref0 and ref1 that has a >>>> built in GPS receiver. They were $175 but they go all over the place in >>>> price. But it does just work. >>>> Trace-ability is an interesting word around this group. From your >>>> description not sure thats really a need. Accept for the oven oscillator >>>> they all are great and yes even really good oven oscillators are great and >>>> can actually be amazing. Not cheap at all though. >>>> You describe your counter and sig gen they have a resolution of .1Hz so >>>> going further isn't really all that helpful. >>>> Now here is the real issue you face and its far more of an issue then you >>>> expect. >>>> First the generator and oscillator and suddenly you find yourself >>>> acquiring more stuff. Maybe a RB, then a Cesium, distribution amplifiers, >>>> better antennas. Sound familiar? You are doooomed. Back away real fast. >>>> Good luck >>>> Paul >>>> WB8TSL >>>> >>>>> On Sun, Jan 10, 2016 at 2:42 PM, Bob Camp <[email protected]> wrote: >>>>> >>>>> Hi >>>>> >>>>>> On Jan 10, 2016, at 1:25 PM, Nathan Johnson <[email protected]> wrote: >>>>>> >>>>>> Hello All, >>>>>> I'm a ham radio operator, for just a few years, and electronics nut >>>>>> for >>>>> many >>>>>> more. I have been reading the archives and trying to learn a bit. I >>>>>> am >>>>> wanting >>>>>> to develop an accurate frequency standard for "lab" and radio use. I >>>>>> see >>>>> that I >>>>>> have 3 basic options that are possible on my budget, a decent >>>>>> OCXO-based >>>>> device, >>>>>> a rubidium standard, and a GPSDO. My current uses are to supply >>>>>> accurate >>>>> timing >>>>>> to a signal generator(not yet purchased, HP 8640/8650-something) and >>>>>> a >>>>> frequency >>>>>> counter(Fluke 1953), mostly used in aligning radios. >>>>>> In the near future I am hoping to expand that to a homebrew HF >>>>>> transceiver(probably clocking a DDS chip of some sort), and some >>>>>> higher frequency(possibly up to 10GHz) transverters. >>>>>> So what I have learned so far about each option: >>>>>> -OCXO is probably stable enough for what I am trying to do, but by >>>>>> itself provides no guarantee of absolute accuracy(I'm looking at the >>>>>> microwave operators "weapon of choice", the Isotemp 134-10), has an >>>>>> adjustment pin >>>>> for a >>>>>> tuning voltage, but no idea what an appropriate value is for that >>>>>> voltage without access to a more accurate standard. I will probably >>>>>> build an >>>>> OCXO device >>>>>> of some kind anyway as an interim measure while I earn for the money >>>>>> to >>>>> obtain >>>>>> something better, and to validate a distribution amp within the lab >>>> etc. >>>>>> -Rubidium Standard seems like a very nice idea, but it's still not >>>>> traceable in >>>>>> terms of absolute accuracy(although the adjustment range of the >>>>>> available standards appears to be several orders of magnitude better >>>>>> than I am >>>>> likely to >>>>>> need). The available standards are being re-imported from China, >>>>>> with >>>>> unknown >>>>>> hours or life remaining, and in some cases unknown condition. They >>>>> appear to be >>>>>> power hogs. A $200 gamble. >>>>>> -GPSDOs have many options available, and are referenced to primary >>>>> standards. >>>>>> Pretty sure this is where I want to go. I'm looking at Item# >>>>> 231803015799 on the >>>>>> usual auction site, and this seems to be everything I need? I also >>>>> looked at >>>>>> item# 111514491254, but there doesn't seem to be any documentation >>>>>> about >>>>> what's >>>>>> inside. >>>>> >>>>> The first item you reference is a Nortel GPSTM with all the “stuff” to >>>>> make it work other than the power supply. If you dig into the >>>>> archives, there is a *lot* of information on them there. >>>>> >>>>> The second item is a Chinese Ham built GPSDO without the antenna. It >>>>> has the nice feature of being actively developed. If you can read >>>>> Chinese, you can tune in to the lists that have information on it. >>>>> >>>>> Of the two, I’d go for the first one from a US seller that I’ve had >>>>> good luck with. >>>>> >>>>> A somewhat more “do it yourself” option is: >>>>> >>>>> >>>>> http://www.ebay.com/itm/221852021307?_trksid=p2055119.m1438.l2649&ssPa >>>>> geName=STRK%3AMEBIDX%3AIT >>>>> >>>>> combined with a GPS receiver board. They also are available in a “2 >>>>> for a bit less” form from the same seller. >>>>> >>>>> Each item has it’s plusses and minuses. The third item has a pretty >>>>> clean >>>>> 15 MHz output for microwave use. >>>>> All of the 10 MHz outputs are a bit dirty noise wise if you decide to >>>>> multiply them up to > 10 GHz. The normal approach in that case is to >>>>> lock up a clean 100 to 150 MHz range VCXO to the GPSDO and then >>>>> multiply the VCXO output to microwaves. >>>>> >>>>> All of them are quite adequate to supply a reference to a signal >>>>> generator or a counter. All are good enough for normal HF radio use. >>>>> >>>>> Bob >>>>> >>>>> >>>>> >>>>>> Am I missing key points here? Or am I headed on the right path? >>>>> Appriciate any >>>>>> and all input. >>>>>> Nathan KK4REY >>>>>> >>>>>> Sent using CloudMagic Email >>>>>> [ >>>>> https://cloudmagic.com/k/d/mailapp?ct=pi&cv=7.4.15&pv=9.1&source=email >>>>> _footer_2 >>>>> ] >>>>>> _______________________________________________ >>>>>> 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. >>>> >>>> >>>> >>>> -- >>>> If this email is spam, report it to >>> https://support.onlymyemail.com/view/report_spam/ODExMjI6MTg0MTUzMTgyNTpyb2JAbmMwYi5jb206ZGVsaXZlcmVk >>>> >>>> _______________________________________________ >>>> 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. >>> >>> >>> >>> -- >>> If this email is spam, report it to >>> https://support.onlymyemail.com/view/report_spam/ODExMjI6MTg0MTY4OTMyMzpyb2JAbmMwYi5jb206ZGVsaXZlcmVk >> _______________________________________________ >> 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. > > > > -- > If this email is spam, report it to > https://support.onlymyemail.com/view/report_spam/ODExMjI6MTg0MTgyMjg0Nzpyb2JAbmMwYi5jb206ZGVsaXZlcmVk > _______________________________________________ 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.
