Re: [time-nuts] And you thought you were old
Doesn't that mean that we're 'due' for some great propagation again? If so, how will that affect our reception of WWV and WWVB? Perhaps we will be entering a time of great time keeping with multiple sources for precise signals... Tom Frank, KA2CDK On Apr 20, 2010, at 4:47 PM, Bill S wrote: Got my license in 1952 and the propagation was unbelievable on 10 and 20 meters into the 60's. Bill S W2FMA Raj wrote: '59 was one of the biggest peaks of propagation if I remember being told by my OT Elmer Les vu2ak. 10W AM to the US from VU. early 60's. Could hear the whole world on it with a piece of wire. Conditions on 10 were great then. 73 - Mike ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] 4501 Netclock
Has anyone successfully used a Thunderbolt GPS with a 4501 Netclock based on the design that John Ackermann describes on his web page. As far as the 10 MHz and 1PPS signals, they should be no problem. What I am concerned about is whether or not the Thunderbolt RS-232 port supplies the time information in the correct format. Also, I am interested in other options for a Netclock OS as opposed to NanoBSD. If NanoBSD is the best way to go, that is the OS that I will use. I am trying to avoid loading a PC with another OS just to build the Netclock. Not that I am lazy, it is a matter of available free time. something that is in short supply these days. Joe ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] And you thought you were old
In case the moderators of this list are unhappy with this thread, it and other similar threads would be welcome on my fun with transistors list. In fact, the list owner, that's me, really enjoys them. See below my signature if you are interested. Regards. Max. K 4 O D S. Email: m...@maxsmusicplace.com Transistor site http://www.funwithtransistors.net Vacuum tube site: http://www.funwithtubes.net Music site: http://www.maxsmusicplace.com To subscribe to the fun with transistors group send an email to. funwithtransistors-subscr...@yahoogroups.com To subscribe to the fun with tubes group send an email to, funwithtubes-subscr...@yahoogroups.com - Original Message - From: "Poul-Henning Kamp" To: "Discussion of precise time and frequency measurement" Sent: Wednesday, April 21, 2010 2:54 AM Subject: Re: [time-nuts] And you thought you were old In message <8e8d23d235d70840b6582917df27898006935...@temps153538.tms-ltd.com>, Reeves Paul writes: I did the same (a VERY long time ago...) with the OC71. In Datamuseum.dk we're presently in the process of restarting a "GIER" computer, the second Danish built computer, and if you happen to have a stash of OC71's laying around, we would happily take them as a donation :-) Poul-Henning http://datamuseum.dk/site_dk/rc/gierdoc/ http://datamuseum.dk/site_dk/rc/giersimulator/ -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS 1 PPS accuracy limits
Date: Tue, 20 Apr 2010 18:59:20 -0700 From: jimlux Subject: Re: [time-nuts] GPS 1 PPS accuracy limits >Do they have other requirements (Allan deviation? phase noise?) >Over what time span do they want 4E-11 accuracy? 1 second, 1000 seconds, >days? >A synthesizer locked to a Stanford Research PRS10 (datasheet accuracy >5E-11) is in that ballpark. They have phase noise requirements, which aren't achievable for the price they want to pay. But phase noise is determined by the OCXO and other circuitry. I suspect the most likely answer is they wrote the spec wrong, and don't really mean 1 Hz absolute accuracy. I'll talk to them and clarify. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS 1 PPS accuracy limits
Hi Does accuracy include temperature change over -55 to +85 C at a 1 C / minute rate? Is accuracy measured after a 5 minute cold start at any temperature? Does accuracy include a contribution internal to the synthesizer (like DDS step size)? Is accuracy simply "where we set it when we shipped it"? There are *lots* of variations to this particular spec Bob On Apr 20, 2010, at 5:59 PM, saidj...@aol.com wrote: > Hi Magnus, Life speed, > > what does accuracy mean? Average (rms, 1-Sigma) frequency accuracy? If yes, > over what time frame is the average? > > Or is this the peak to peak allowable deviation? Over what temperature > range, and after how long of a warmup? > > To give you an example, a typical Fury desktop unit with DOCXO is capable > of better than 2us holdover drift per day after 3 to 5 days of constant > operation. > > That equates to an average frequency accuracy over one day without GPS of > <2.3 x 10^-11. > > With GPS the accuracy on average is better than 2E-012 after about an hour > or so averaging. > > bye, > Said > > > > > In a message dated 4/20/2010 13:07:53 Pacific Daylight Time, > mag...@rubidium.dyndns.org writes: > > life speed wrote: >> Time Nuts; >> >> I have a customer request for a microwave frequency synthesizer with > extreme accuracy requirements; >> 4 X 10^-11, or 0.04 PPB. Obviously this is way out of quartz oscillator > territory. >> Is GPS 1 pulse-per-second useable, or do they need an atomic clock? >> Maybe they don't realize what they are spec'ing. > > I really think you should ask them to motivate themselves on that spec, > the intended use etc. They can certainly get a spec like that, but is it > what they need? > > You certainly want something like a GPS clock to feed that thing if they > really need that level of accuracy. Or do they only need that level of > resolution? > > Cheers, > Magnus > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] And you thought you were old
I think I still have a few OC71 xistors Dave Partridge ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] And you thought you were old
In message <8e8d23d235d70840b6582917df27898006935...@temps153538.tms-ltd.com>, Reeves Paul writes: >I did the same (a VERY long time ago...) with the OC71. In Datamuseum.dk we're presently in the process of restarting a "GIER" computer, the second Danish built computer, and if you happen to have a stash of OC71's laying around, we would happily take them as a donation :-) Poul-Henning http://datamuseum.dk/site_dk/rc/gierdoc/ http://datamuseum.dk/site_dk/rc/giersimulator/ -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] And you thought you were old
I did the same (a VERY long time ago...) with the OC71. Schoolboy funds could not reach OCP71 levels. They made good phototransistors until Mullard found out and started filling the glass encapsulations with a white compound. Spoilsports :-) But all you had to do was break the glass and scrape off the compound - worked fine. I can't quite envisage doing that with a modern equivalent! 73 Paul ReevesG8GJA -Original Message- From: Jean-Louis Oneto [mailto:jean-louis.on...@obs-azur.fr] Sent: 20 April 2010 19:31 To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] And you thought you were old I used their low power variant (OC45) to make my first audio optical link (free air, analog f course !) using flashtorch parabola as Tx and Rx "antennae". The OC45 was black painted transluscend plastic. You just had to scratch the paint to get a nice phototransitor... - Original Message - From: "Horst Schmidt" To: "Discussion of precise time and frequency measurement" Sent: Tuesday, April 20, 2010 2:52 PM Subject: Re: [time-nuts] And you thought you were old >I still have an original booklet from raytheon : how to build a 1 >transistor radio with a CK722. > > However, my very first transistor first transistor was an OC70 from Valvo > (German Philips). I bought it about 1956 ,I was 13 years old then in > Stuttgart Germany. > > It cost me 10.20 German Marks. A substancial sum then. I soldered the > transistor in to a socket , so the leads would not break off. > I build many different projects with it then. > > Now when I see one of the old black Philips glass encapulated > transistors, I get quite nostalgic. > But this days one hardly looks at a modern transisitor anymore. > > > > > On 21/04/2010 12:19 AM, Mike Feher wrote: >> In fact, one of the first CK-722s that I took apart did have a smaller >> hearing aid type transistor inside. Later CK-722s were of course built as >> CK-722s and even later they were in black but somewhat clear epoxy >> cases. - >> 73 - Mike >> >> Mike B. Feher, N4FS >> 89 Arnold Blvd. >> Howell, NJ, 07731 >> 732-886-5960 >> >> >> >> >> -Original Message- >> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On >> Behalf Of J. Forster >> Sent: Tuesday, April 20, 2010 9:57 AM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts] And you thought you were old >> >> Do you know the story of the CK722? >> >> In the 1950s, Raytheon was making tiny transistors for hearing aids to >> replace the pre-WW II subminiature tubes. >> >> Aside: Those tubes, developed by Norm Krim, were ruggedized and used in >> the WW II Proximity Fuzes, one of THE big inventions of WW II. >> >> Anyway, Raytheon was making piles of these tiny transistors, but many >> were >> not making hearing aid specs. Norm got the idea of packaging them to sell >> to hams to learn about transistors. If you open up one of the blue ones, >> there is another tiny case inside which is the real transistor. >> >> BTW, Norm is still alive and well in his 90s. >> >> -John >> >> === >> > Anyone remember the CK722 transistor? As I remember they were about $7.50, >>> a >>> considerable sum. >>> ___ >>> time-nuts mailing list -- time-nuts@febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >>> >>> >> >> ___ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> __ Information from ESET NOD32 Antivirus, version of virus >> signature database 5044 (20100420) __ >> >> The message was checked by ESET NOD32 Antivirus. >> >> http://www.eset.com >> >> >> >> >> > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. This email, including any attachment, is a confidential communication intended solely for the use of the individual or entity to whom it is addressed. It contains information which is private and may be proprietary or covered by legal professional privilege. If you have received this email in error, please notify the sender upon receipt, and immediately delete it from your system. Anything contained in this email that is not connected with the businesses of this company is neither endorsed by nor is the liability of this company. Whilst we have taken reasonable precautions to ensure that any attachment to this email has been swept for
