Re: [time-nuts] Building a DMTD/phase noise set in the 21st century
Mine exhibit a series resistance of a few tens of milliohms and the added thermal noise was insignificant. The manufacturer claimed to use nanostructured carbon electrodes. The leakage current was also small Bruce > On 30 August 2019 at 11:19 Gerhard Hoffmann wrote: > > > > Am 26.08.19 um 04:47 schrieb Bruce Griffiths: > > I've only used an ultra low esr 33F supercap made in Korea in the source > > circuit of the input JFET on a preamp. > > Down to 10Hz at least it didn't appear to add significant noise to the > > 4nV/rtHz @10Hz preamp. > > I had bought some at DK, but 30 Ohms or worse at AC in the source > produce >700pV/rtHz alone. > > That would add (geometrically) to the 300 pV/rtHz of one Interfet > IF3601/3602 > > and spoil the pot, so I stayed with the multiple electrolytics with > milliOhms. > > regards, > > Gerhard > > > > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] GPS Antennas
I think several people have run into that issue, including myself. It seems designed for a slightly tapered rod. Easy to fix with the right tool. Denny > On Aug 29, 2019, at 16:41, Ben Hall wrote: > > Only issue with mine was that the thread wasn't fully cut, so I modified an > old taper tap to be a bottoming tap with the bench grinder and finished > tapping the hole to the bottom. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Marine GPS antenna at SF Bay Area surplus shop
Hello Gary, I went by Excess Solutions today in San Jose and picked up two of these - they are in a box on the "antenna aisle - (6)" toward the end of the aisle on the RHS at the top. There were actually around 10 or so in that box - so there's at least 8 left as of this afternoon. They all appear to be new and unused. Thanks for posting and letting us know about this. 73's, John AJ6BC On Thu, Aug 29, 2019 at 9:31 AM Gregory Beat via time-nuts < time-nuts@lists.febo.com> wrote: > BJTEK Navigation > Brand name: “Antenna King” > 2F., No.129, Daxue Rd., > Sanxia Dist., New Taipei City 237, > Taiwan(R.O.C.) > http://marine.antennaking.com.tw/index00a8.html?lang=2 > > Tel : 886-2-86720160 > Fax : 886-2-86720161 > e-Mail : sa...@bjtek.com.tw > > BJTEK GA-62P-SMA(F) model > Brochure / Datasheet > http://marine.antennaking.com.tw/comm/upfile/d_100603_07203.pdf > > This provides additional details on this surplus GPS antenna at Excess > Solutions. > > greg, w9gb > == > From: gary > To: time-nuts > Subject: [time-nuts] Marine GPS antenna at SF Bay Area surplus shop > > http://marine.antennaking.com.tw/detail/322578/322578.html > At Excess Solutions. They have a few of these mystery brand active GPS > antennas for $8. Looks like this link except no cable provided. They had > about half a dozen. > The lock mount is in the bottom of the bin in a plastic bag. > > My GPSDO uses 12V , > so I guess I will have to test this on a portable GPS. > == > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Building a DMTD/phase noise set in the 21st century
Am 26.08.19 um 04:47 schrieb Bruce Griffiths: I've only used an ultra low esr 33F supercap made in Korea in the source circuit of the input JFET on a preamp. Down to 10Hz at least it didn't appear to add significant noise to the 4nV/rtHz @10Hz preamp. I had bought some at DK, but 30 Ohms or worse at AC in the source produce >700pV/rtHz alone. That would add (geometrically) to the 300 pV/rtHz of one Interfet IF3601/3602 and spoil the pot, so I stayed with the multiple electrolytics with milliOhms. regards, Gerhard ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] GPS Antennas
On 8/29/2019 11:59 AM, Dan Kemppainen wrote: I recall some talk about the cheap multi-band units on ebay that that are compatible with the f9P modules. Can anyone report back how they worked out? I'm very happy with the one I bought and received from that seller. Haven't tried it with an F9 yet, but the M8T's, TruePositions, NTPi, and Blitzortung System Blue all work very well on it via my 8-way passive splitter modified for DC block on 7 of the 8 channels. (the voltage feed for the antenna comes from one of the TruePosition units) Only issue with mine was that the thread wasn't fully cut, so I modified an old taper tap to be a bottoming tap with the bench grinder and finished tapping the hole to the bottom. Thanks much and 73, ben, kd5byb ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
[time-nuts] GPS Antennas
They work very well. I get the same results as with a $5000 L1/L2 survey antenna. My antenna location is horrible, so there may be some difference with a better location... but I doubt it would be noticeable for most users. I used F9P, F9T, NetRS and Z12 receivers. > Can anyone report back how they worked out? ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
[time-nuts] GPS Antennas
Hi All, For the second summer in a row we were smacked with lightning. So I'm in need of a new GPS antenna. Might as well look for one with multi band units. I recall some talk about the cheap multi-band units on ebay that that are compatible with the f9P modules. Can anyone report back how they worked out? The link from a while back is as follows: https://www.ebay.com/itm/CORS-RTK-GNSS-Survey-Antenna-high-gain-measurement-GNSS-GPS-GLONASS-BDS/253786590956 Thanks! Dan ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Marine GPS antenna at SF Bay Area surplus shop
BJTEK Navigation Brand name: “Antenna King” 2F., No.129, Daxue Rd., Sanxia Dist., New Taipei City 237, Taiwan(R.O.C.) http://marine.antennaking.com.tw/index00a8.html?lang=2 Tel : 886-2-86720160 Fax : 886-2-86720161 e-Mail : sa...@bjtek.com.tw BJTEK GA-62P-SMA(F) model Brochure / Datasheet http://marine.antennaking.com.tw/comm/upfile/d_100603_07203.pdf This provides additional details on this surplus GPS antenna at Excess Solutions. greg, w9gb == From: gary To: time-nuts Subject: [time-nuts] Marine GPS antenna at SF Bay Area surplus shop http://marine.antennaking.com.tw/detail/322578/322578.html At Excess Solutions. They have a few of these mystery brand active GPS antennas for $8. Looks like this link except no cable provided. They had about half a dozen. The lock mount is in the bottom of the bin in a plastic bag. My GPSDO uses 12V , so I guess I will have to test this on a portable GPS. == ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
