[time-nuts] An update on my Efratom FRK with "inoperative lamp"

2022-03-08 Thread Julien Goodwin
As the project has now stalled I figured I'd send another update on my FRK with the current state. The FRT: Although the replacement cap I'd picked up (KEMET PEH169MD4470QB2) was perfect in two dimensions plus the mounting, it turned out to be way to tall. I'll pick up a smaller option at

[time-nuts] Re: Efratom FRK with "inoperative lamp"

2022-02-25 Thread Julien Goodwin
still waiting on some safer probe options. On 15/2/22 6:10 pm, Darren Freeman wrote: On Sat, 2022-02-05 at 20:48 +1100, Julien Goodwin wrote: I /think/ it's using more power than it did before (right around 20W at total cold, dipping to 10W after a while), although silly me didn't make a note

[time-nuts] Re: Efratom FRK with "inoperative lamp"

2022-02-10 Thread Julien Goodwin
On 6/2/22 1:14 am, Matthias Welwarsky wrote: On Samstag, 5. Februar 2022 10:48:57 CET Julien Goodwin wrote: I /think/ it's using more power than it did before (right around 20W at total cold, dipping to 10W after a while), although silly me didn't make a note of it, but even after 30 minutes

[time-nuts] Re: Efratom FRK with "inoperative lamp"

2022-02-05 Thread Julien Goodwin
the expected glow. I did confirm the heater is working, and was getting above 90c when I poked a thermocouple at it just after power-off. 1: https://www.edn.com/honoring-jim-williams/ On Fri, Feb 4, 2022 at 3:50 AM Julien Goodwin wrote: Well that was unexpectedly easy (to diagnose). Thanks all

[time-nuts] Re: Efratom FRK with "inoperative lamp"

2022-02-04 Thread Julien Goodwin
On 4/2/22 5:15 pm, Julien Goodwin wrote: Well that was unexpectedly easy (to diagnose). Thanks all for the replies, much appreciated, you have once again confirmed my appreciation for this group. I sat down this evening to work through your various suggestions, and, by chance, picked up

[time-nuts] Efratom FRK with "inoperative lamp"

2022-02-01 Thread Julien Goodwin
I picked up an Efratom FRT a while ago, and it finally arrived the other day, sadly it doesn't lock. The oscillator inside is an older Efratom FRK, and it's also clear someone had been inside already, although it does appear to be complete. The FRK manual does include a key description I

[time-nuts] Re: Micrel (Microchip) PL-500 Low Phase Noise VCXO

2021-10-17 Thread Julien Goodwin
On 20/9/21 5:37 pm, Julien Goodwin wrote: > > > On 18/9/21 11:12 pm, Julien Goodwin wrote: >> >> >> On 18/9/21 10:26 pm, Bob kb8tq wrote: >>> Hi >>> >>> The chip is intended to be used with the divider engaged ( set to a divide >&

[time-nuts] Re: Hafele-Keating, 50 years ago today

2021-10-17 Thread Julien Goodwin
On 6/10/21 2:50 am, Bob kb8tq wrote: > Hi > >> On Oct 5, 2021, at 11:33 AM, Tom Van Baak wrote: >> >> The Hafele-Keating experiment was performed 50 years ago. Starting October >> 4th, 1971, Joe Hafele and Dick Keating took 4 hp cesium clocks on an >> airplane trip, a very long trip, all the

[time-nuts] Re: Best Leo Bodnar configuration for 10MHz

2021-09-27 Thread Julien Goodwin
On 14/9/21 4:17 pm, Marek Dorsic wrote: > Hi Community, > >I received my Leo Bodnar Mini GPS Reference Clock. > The same 10MHz output frequency can be achieved by varios configuration > settings. > Are some of these combinations better than others? > Since I'm currently in the "playing

[time-nuts] Re: Micrel (Microchip) PL-500 Low Phase Noise VCXO

2021-09-20 Thread Julien Goodwin
On 18/9/21 11:12 pm, Julien Goodwin wrote: > > > On 18/9/21 10:26 pm, Bob kb8tq wrote: >> Hi >> >> The chip is intended to be used with the divider engaged ( set to a divide >> of >> 2 or greater). That should act as a pretty good buffer if the la

[time-nuts] Re: Micrel (Microchip) PL-500 Low Phase Noise VCXO

2021-09-17 Thread Julien Goodwin
On 13/9/21 6:31 pm, Julien Goodwin wrote: > https://www.microchip.com/en-us/product/PL500-16 (there's various other > versions depending on the frequency you're after) > > Haven't seen any discussion about this on-list, but the PL500 is an > easily (well, in normal times) availab

[time-nuts] Re: Micrel (Microchip) PL-500 Low Phase Noise VCXO

2021-09-13 Thread Julien Goodwin
On 14/9/21 1:42 pm, Lux, Jim wrote: > On 9/13/21 7:36 PM, Julien Goodwin wrote: >> >> On 14/9/21 12:59 am, Chris Caudle wrote: >>> On Mon, September 13, 2021 3:31 am, Julien Goodwin wrote: >>>> https://www.microchip.com/en-us/product/PL500-16 >>&g

[time-nuts] Re: Micrel (Microchip) PL-500 Low Phase Noise VCXO

2021-09-13 Thread Julien Goodwin
On 14/9/21 12:59 am, Chris Caudle wrote: > On Mon, September 13, 2021 3:31 am, Julien Goodwin wrote: >> https://www.microchip.com/en-us/product/PL500-16 > ... >> I've designed as an OCXO > > What temperature are you planning on running the oven? If that device is

[time-nuts] Micrel (Microchip) PL-500 Low Phase Noise VCXO

2021-09-13 Thread Julien Goodwin
https://www.microchip.com/en-us/product/PL500-16 (there's various other versions depending on the frequency you're after) Haven't seen any discussion about this on-list, but the PL500 is an easily (well, in normal times) available VCXO control chip, for those who might want to make their own

[time-nuts] Re: About 10 MHz Optical Distro

2021-08-29 Thread Julien Goodwin
On 30/8/21 5:24 am, Lux, Jim wrote: > Yeah, but those are piece parts.  What would be nice is if a cheap "box" > could be found - ideally (for 10 MHz) BNC in/out and fiber connector > with a wall wart for power. Maybe this a good idea for a TAPR project if > someone was willing to do the design

[time-nuts] Re: of possible interest

2021-08-28 Thread Julien Goodwin
On 21/3/20 6:07 am, djl wrote: > > https://www.sv1afn.com/en/products/vhf-uhf-triplexer-1.html > > 10 mhz and uhf/vhf on same cable. I've pondered if IRIG modulated on 10MHz would make enough sense to work, or if the modulation would end up degrading the 10MHz enough to no longer be a good

[time-nuts] Re: Comparison/evaluation of u-blox timing receivers

2021-08-28 Thread Julien Goodwin
On 24/8/21 11:51 am, John Ackermann N8UR wrote: > In 2020 I did an extensive evaluation of the timing ability of the > u-blox LEA-M8F, NEO-M8N, NEO-M8T, NEO-M9N, ZED-F9P, and ZED-F9T.  The > work was made possible by support from the HamSci consortium > (https://hamsci.org) under NSF grants

[time-nuts] Re: Stanford Research SR620 GBIB

2021-08-28 Thread Julien Goodwin
> 73. > > Dave G8KBV. > > > Message: 4 > Date: Sat, 28 Aug 2021 17:03:09 +1000 > From: Julien Goodwin > Subject: [time-nuts] Stanford Research SR620 GBIB > To: Discussion of precise time and frequency measurement > > Message-ID: <4e137f33-67e5-c00c

[time-nuts] Stanford Research SR620 GBIB

2021-08-28 Thread Julien Goodwin
For an upcoming (very time-nutty, and hopefully to be shared soon) project I need to finally do some frequency datalogging. I've had a Stanford SR620 sitting around, and plugged it in to a handy GPIB adapter (*not* a major commercial one, one of the community ones). While I can get it to talk

[time-nuts] Re: 20th year of time nuts mailing list

2021-07-06 Thread Julien Goodwin
On 1/1/21 4:02 pm, 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

[time-nuts] Re: GPS antenna distribution???

2021-06-29 Thread Julien Goodwin
I keep forgetting to do a thread about this. I recently (er, perhaps a year ago) picked up a Microlab unit, and was very disappointed, notably the output simply isn't built to handle being plugged into units that provide antenna power, with each port ending up having a DC path to ground (at 200

Re: [time-nuts] Building new pods for the Spectracom 8140 using modern components

2019-04-28 Thread Julien Goodwin
On 28/4/19 3:25 am, John Ackermann N8UR wrote: > I have a large box of 8140 pods (well, I call them "taps").  They are > quite handy for stringing distribution points around a large room, > provided ultimate phase noise performance isn't required. > > You *don't* need an 8140 main box to use

[time-nuts] Building new pods for the Spectracom 8140 using modern components

2019-04-27 Thread Julien Goodwin
Slightly edited down from my blog, if you want the full thing with photos see: https://laptop006.livejournal.com/60862.html I've mentioned a bunch of times on the time-nuts list that I'm quite fond of the Spectracom 8140 system for frequency distribution. For those not familiar with it, it's

Re: [time-nuts] inexpensive fiber optic distribution

2019-03-21 Thread Julien Goodwin
On 21/3/19 5:27 pm, Hal Murray wrote: > > jim...@earthlink.net said: >> It seems like you could probably figure out how to interface to these things >> and use them to distribute timing signals. > > There are two big advantages of fibers: > They work well for long distances. > No ground

Re: [time-nuts] Distribution amplifier for 10MHz and 1 pps

2019-03-18 Thread Julien Goodwin
The 74S140 (dual 4-input NAND) is the classic TI TTL 50-ohm driver. They're still available in DIP & SOIC. I'm currently waiting on some boards to arrive so I can try SN74LVC1G17 as a more modern replacement that's much cheaper and smaller. Once I've proven it I'll do a separate thread to the

Re: [time-nuts] Synthesized Signal Generator query

2019-03-08 Thread Julien Goodwin
On 8/3/19 1:19 am, Don@True-Cal wrote: > Hi Jim, > The 100K to 3G frequency range of the 8664A is what I'm looking for as a > general signal source. The low phase noise needed will mostly be under > 100MHz for work on clock, trigger and timing circuits. Thanks for the reply, If you're willing to

Re: [time-nuts] HP Stories: Battery Chargers, and a fading idolization of HP

2019-02-18 Thread Julien Goodwin
On 10/2/19 11:18 pm, Rice, Hugh (IPH Writing Systems) wrote: > The AC transformer in the 5061A/B was from HPs transformer organization (HP > actually made their own transformers for many years), and whoever designed > the original power system left a lot of "brown out" margin in the system.

Re: [time-nuts] Atomic Clocks: It is important that they keep good time, Part 1

2019-01-06 Thread Julien Goodwin
On 5/1/19 6:45 am, paul swed wrote: > Yes indeed I also would like one of the analog clocks. But be careful what > you ask for > I have a friend in Switzerland that does have a 5065 with the analog clock. > It tends to drive you a bit crazy with the tick of the step so he says. I > may believe

[time-nuts] uBlox GPS Compendium

2018-12-24 Thread Julien Goodwin
Although far more focused on the position aspects this is a good read that I don't recall coming up on this list before. https://www.u-blox.com/sites/default/files/products/documents/GPS-Compendium_Book_%28GPS-X-02007%29.pdf ___ time-nuts mailing list

[time-nuts] uBlox GPS Compendium

2018-12-24 Thread Julien Goodwin
Although far more focused on the position aspects this is a good read that I don't recall coming up on this list before. https://www.u-blox.com/sites/default/files/products/documents/GPS-Compendium_Book_%28GPS-X-02007%29.pdf ___ time-nuts mailing list

Re: [time-nuts] MEMS oscillators

2018-10-31 Thread Julien Goodwin
Reminds me a little of the crazy Eidophor projectors. "An Eidophor was a television projector used to create theater-sized images. The name Eidophor is derived from the Greek word-roots ‘eido’ and ‘phor’ meaning 'image' and 'bearer' (carrier). Its basic technology was the use of electrostatic

Re: [time-nuts] Symmetricom (Datum/Microsemi) CS tubes after storage

2018-08-14 Thread Julien Goodwin
/images/cs4000_monitor3-2018-08-14.png On 25/06/18 11:52, Julien Goodwin wrote: > Thanks for the on & off-list responses folk. > > Sadly I didn't have a usable RS232 adapter set when I first powered this > on a month back. It's actually on a desk I'm borrowing in Sunnyvale[1] > (

Re: [time-nuts] Symmetricom (Datum/Microsemi) CS tubes after storage

2018-06-25 Thread Julien Goodwin
better insights. > Good luck. > Regards > Paul. > > On Wed, Jun 20, 2018 at 7:32 PM, Julien Goodwin > wrote: > >> I recently picked up a used Cs clock (Symmetricom labelled Cs4000). >> >> Sadly, it turns out to have been stored for about a year (at least, a >>