[time-nuts] Another oldie

HP 103A from a swap meet https://goo.gl/photos/S5RNSvFigrm8TSeY9 ___ 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] Cesium tube magnets

h oooh I want a set. ! any idea how many gauss? Dave On 4/8/2017 8:31 PM, cdel...@juno.com wrote: Here are some magnets from an HP Cesium tube. It shows one pair of state selection magnets, (there are two pairs in each tube), and the magnet for the ion pump. Cheers, Corby

[time-nuts] FTS Ramsey cavity

A friend asked me a while ago why the FTS Cesium tubes were so light. Since they were designed from the beginning to fit in a 5.25" high chassis that cut quite a bit of the weight. However a large amount of weight was saved by using a Ramsey cavity that was not milled from a massive block of

Re: [time-nuts] TAPR TICC boxed (input protection)

David wrote: I mentioned this in connection with some manufacturers using gold doping in transistors which would not normally be expected to have gold doping. So you end up with a bunch of lessor named 2N3904s which meet the 2N3904 specifications but are useless if you were looking for low

[time-nuts] HP5061B Cold Start

https://www.febo.com/pipermail/time-nuts/2017-April/thread.html We performed an experiment with our working HP5061B which had been cold overnight. This was to better determine lock time from cold ovens. We found that the crystal oscillator oven heats up about twice as fast as does the cesium

Re: [time-nuts] TAPR TICC boxed (input protection)

David wrote: So gold doping does work with PNP devices. Previously when I brought it up, I was told gold doping only applied to NPN devices leading to my confusion. Since I posted, I dug through my books and found a few more references on point: A couple of textbooks say commercial PNP

Re: [time-nuts] TAPR TICC boxed (input protection)

Am 08.04.2017 um 17:52 schrieb David: If they are not being tested, then where is the maximum specified leakage number coming from? For a small signal bipolar transistor it will typically be 25nA, 50nA, or 100nA, but the InterFET datasheet (1) shows 10pA maximum and 1pA maximum for the A

Re: [time-nuts] TAPR TICC boxed (input protection)

The Siliconix PAD1 at 1pA and 0.8pF is still available : http://www.micross.com/pdf/LSM_PAD1_TO-72.pdf On Sat, Apr 8, 2017 at 4:52 PM, David wrote: > On Thu, 6 Apr 2017 22:23:43 -0400, you wrote: > > >David wrote: > > > >> I know one thing to watch out for if you are

Re: [time-nuts] TAPR TICC boxed (input protection)

You need to be careful how you paint the package black.  My first electronics job was in a place that made, among other things, mass spectrometers.  We made very high input impedance electrometers for the mass specs using TO-5 can mosfet transistors.  One batch was found to be very photo

Re: [time-nuts] TAPR TICC boxed (input protection)

On Thu, 6 Apr 2017 22:23:43 -0400, you wrote: >David wrote: > >> I know one thing to watch out for if you are looking for low >> leakage is gold doping > >Anything that increases carrier mobility increases leakage current (all >else equal -- i.e., for each particular device geometry). This

Re: [time-nuts] TAPR TICC boxed (input protection)

On Fri, 7 Apr 2017 01:06:17 -0400, you wrote: >Another thing to watch out for if you need very low leakage, is if the >package is transparent. All junctions are photodiodes. > >Maybe it's less of a problem now with SMTs, than it was with glass body >diodes or translucent transistor packages. >

Re: [time-nuts] TAPR TICC boxed (input protection)

On Fri, 7 Apr 2017 04:09:38 -0400, you wrote: >David wrote: > >>> what doping is used for PNP RF transistors and saturated switches >>> if it is not gold? Does it also increase leakage? > >I replied: > >> Gold doping doesn't affect the speed of BJTs in the active region very >> much -- its

Re: [time-nuts] The ultraAtomic clock for home

Mike you may have missed it in the thread. I made a mistake its not the cme8000 chip. Thats a classic am decoder. *You want the ES100*. Thats a true wwvb bpsk decoder. Contact La Crosse and ask if they have a model. Regards Paul WB8TSL On Fri, Apr 7, 2017 at 1:18 PM, Mike Seguin