Fellow time-nuts, In the end of the previous millennia I got involved in a handful of email-lists pertaining to analog (musical) synthesizer and building of these. I then ended up with the opportunity of buying some test-gear to aid my endeavors on trimming the oscillators. It's a bit of a challenge, since you have an exponential converter that transforms a 1 V/Oct voltage over to a current linear with frequency, using NP-junction properties. Then this current is used convert into a sawtooth or triangular shape using a capacitor and a reset circuit, of which the later has a fixed reset-time. A good expo-converter can span over 20 octaves. Trimming this to "track properly" and be temperature stable is a challenge. So, I was able to acquire a pair of bench DMMs in form of HP 3457A, a frequency counter in form of HP5335A and a R&S XSRM Rubidium reference out of Ericsson as they closed one of their factories and also calibration labs. Great. I also got a HP4195A network analyzer and HP3325B function generator. Not a bad setup. However, I wanted to learn more about oscillators. I was searching the net using AltaVista, found the NIST T&F archive, I found variour other sources, learned that there is a stability measure called Allan Deviation and phase-noise, and started to read up a lot. I then also found this little quirky email-list for people that really like time and frequency and being kind of nuts, called time-nuts. You might have heard about them. I ended up learning a lot quickly. In parallel at work I was working with jitter in digital transmission and how that cause bit errors, synchronization and how to build synchronization over the full network. I ended up joining the IEEE UFFC, as this allowed me to get access to that library of articles.
Over time I have seen my lab outgrow the room it started in, I now lost count of the number of rubidiums I have, I barely know how many cesiums I have and the once unobtainium of a hydrogen maser obviously takes a big part of the new lab and is fortunately easy to count so far (1). Counter-wise I also got a rather sizeable collection, some of which I have more for museum/reference purposes than anything I can meaningful use. I can measure ADEV and phase-noise fairly well, to the level that I was appaulled by the huge 10 ps spikes that the RS232 readout was causing, and here I thought 10 ps resolution was unobtainable not that far ago. I have presented at EFTF and IFCS, have a PTTI presentation to finalize now. I know a whole range of the people behind the names of the articles I read. Over the years I learned a lot just hanging out on the list, and I have hopefully contributed some. It's been an awesome journey. There is still things to learn, and just reading the list is a great way to learn things. Also at times, I find myself reminded rather than learning, but that is important too. Cheers, Magnus On 2021-01-01 06:02, Tom Van Baak wrote: > Hello time nuts, > > Ah, it is 2021-01-01 (JD 2459215.5, MJD 59215) which is nice because > that means it's not 2020 anymore. > > One reason I've been looking forward to 2021 is that it's now > officially the 20th year of the time nuts mailing list. So this is a > note to say *thank you* to everyone for making it so amazing over the > years. I get comments all the time about this mailing list; its depth, > its high SNR, its focus, its vast archive of quality postings, and > especially, the community that evolved around the list. > > On the web the phrase "time nut" is now a proper noun, sometimes an > adjective, or occasionally a diagnosis or disease. Never in my wildest > dreams did I think any of this would happen. I thought my early > interest in nixie tubes, clocks, electronics, and precise timing might > be a passing phase, and that the frequency of eBay purchases would > fade. But no. This turns out to be an incredibly wide, deep, > interesting, and rewarding hobby. The mailing list started with 6 > people (half of whom are still active) and we now have 1850 members. [1] > > Speaking of history, and also to put time-nuts into perspective, I'd > like to mention that leapsecond.com (tvb) and febo.com (jra) predate > Y2K (2000), wikipedia (2001), facebook (2004), youtube (2005), twitter > (2006), reddit (2006), iPhone (2007), duckduckgo (2008), gmail (2004, > 2009), eevblog (2009), instagram (2010), snapchat (2011), outlook > (2012), and literally millions of other web sites and mailing lists. > > When this all started for us it was WWV on short-wave, ACTS by phone, > Loran-C, GOES, WWVB, GPS, Win98, dial-up, and my search engine was > altavista.dec.com. It's scary to think how much has changed in 20 > years. Fun fact: I started leapsecond.com so I could post the results > of a Y2K Colorado visit to NIST. If the world was going to crash I was > going to be at ground zero, with a camera. [2] > > Anyway, stay safe, stay healthy, stay timely. Here's to a new decade > and a happy new year to all of us. > > /tvb > > [1] http://leapsecond.com/time-nuts.htm#history > > [2] http://leapsecond.com/y2k/ > > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
