Hi Since few of us have an oil bath to check the thermometer chips with, it's tough to really know what the long term stability is. Those of us that do have sufficiently precise oil baths are a bit reluctant to dunk a TBolt in them on a regular basis....
Bottom line appears to be - fine for day to day checks. I would not trust any of these chips to be long term stable to sub 10 mK levels. Bob On Sep 27, 2010, at 6:53 PM, Heathkid wrote: > Great suggestion! I bought two of the Symmetricom 58535A's from Mike Feher. > It'll be great only having to deal with *one* antenna and feedline plus I'll > have a spare antenna (and a spare splitter - for now)! :) Now... lots of > adapters and patch cables to buy (N to F)... > > I've also bought four (4) DS1620 "D1" chips... so that should keep me in > business for a while. Since one of my Tbolts has an "E2" chip in it... was > there an E1? Did the E2 fix anything or should I just go straight back to > the D1? Is anyone keeping track of the temp chips and any long term > stability data on them? Seems there should be almost a decade of data out > there somewhere... > > Thanks again... > > 73 Brice KA8MAV > > ----- Original Message ----- From: <k6...@comcast.net> > To: <time-nuts@febo.com> > Sent: Monday, September 27, 2010 10:50 AM > Subject: Re: [time-nuts] antennas > > >> Rather than put up two antennas, why not use one, and pick up a >> HP/Symmetricom GPS splitter? (Mini-Circuits makes a similar unit). You can >> find them on eBay for various prices. The Symmetricom one, the 58535A, >> supports 2 GPS receivers. It has a built-in amplifier and filters, so it >> provides high isolation between the GPS units. It's powered from the GPS >> units, and passes power to the antenna. >> >> The downsides are that it costs more than a pair of cheap antennas, it's >> heavy (heavier than the Thunderbolt!), and uses type N connectors. >> >> But it's low noise, and you only have one antenna and feedline to worry >> about. >> >> 73 bob k6rtm >> ------------------------------ >> Message: 3 >> Date: Sun, 26 Sep 2010 15:56:47 -0400 >> From: "Heathkid" <heath...@heathkid.com> >> Subject: Re: [time-nuts] DS1620 Variants in the Thunderbolt >> To: "Discussion of precise time and frequency measurement" >> <time-nuts@febo.com> >> Message-ID: <795f7aa593814ecb9aa24f0b55cad...@d1x25bd10> >> Content-Type: text/plain; format=flowed; charset="UTF-8"; >> reply-type=original >> >> Thanks for all the information on the DS1620. >> >> As it turns out, both of the TBolts (remember I got the from two different >> sellers and appear identical) have the Trimble OCXO, v3.00 firmware, but the >> DS1620's are marked as follows: >> >> DS1620 >> 0415E2 >> 531AD >> >> DS1620 >> 0239D1 >> 690AB >> >> Interestingly, the first one appears to have been swapped out at some point >> (flux residue all over the chip / had to clean it off to read the markings). >> I've already ordered another "D1" to swap out the "E2" but really need to >> get them both up and running (still trying to figure out how to mount the >> antennas!) and see how much difference there really is. >> >> 73 Brice KA8MAV >> >> _______________________________________________ >> 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. > _______________________________________________ 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.
