The 8660 is a rather messy generator with five loops. Its phase noise spec within a 30 kHz bandwidth is nominally 4 dB worse than an HP 3336C. Of course the frequency range of the 8660 is vastly greater than the 3336C, depending on the plugin. There were 4 versions of the 8660, A, B, C & D. I mention the 3336C because while a very handy synthesizer, its phase noise is terrible compared to the 8640A/B. It depends on what you want to do with your generator. As you said, if it can be purchased and shipped for $100, why not. Alignment of the 8660 is a pain, so expect a project. Hopefully it gets packed properly. Shipping damage of large and heavy test equipment is a really big problem.
Rob, NC0B Sent from my iPad > On Jan 14, 2016, at 4:02 PM, "Nathan Johnson" <[email protected]> wrote: > > > > What does the group think of the HP 8660? Just scored a broken one too cheap > to > pass up. I know it's not gonna be the last signal generator I buy, but for > under > $100 shipped it should be an interesting project. > 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 Tue, Jan 12, 2016 at 02:50, Discussion of precise time and frequency > measurement <[email protected]> wrote: > Robs correct on that front. Did not have time to respond till now. > The 8640 is not some sort of synthesized gen. > But it has one of the lowest noise floors of any generator. > So I have several of them and then the synthesized gens like those > mentioned. > > Hear that sucking sound? > Its quicksand. > > Regards > Paul > WB8TSL > >> On Mon, Jan 11, 2016 at 3:54 PM, Rob Sherwood. <[email protected]> wrote: >> >> 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. > _______________________________________________ > 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/ODExMjI6MTg0MzAwOTY3Mzpyb2JAbmMwYi5jb206ZGVsaXZlcmVk > _______________________________________________ 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.
