Re: [time-nuts] Cure for hot 5370B counters

Bob wrote: If you can touch the heat sink for 2 seconds, you're made of sterner stuff than I am! They run very hot. As I've said before, get a little desk fan (see attached photo). Position it behind the counter, blowing straight into the heatsink from 2-3 inches away. The ones I have

Re: [time-nuts] A Leap Second is coming

This is my clock (NTP synchronized) -- with a bit of luck, the second hand will stop (for a second) at the appropriate instant (7PM Eastern). I intend to catch it on video. Unfortunately, this being an inexpensive clock, the plastic gears result in the hands not aligning quite correctly (it

Re: [time-nuts] Anyone (ideally in the UK) got a spare rotary knob for the 5370B TI counter?

You could try hooking up a transformer with a 20V secondary as an autotransformer to reduce the line voltage. On Fri, Dec 30, 2016, 9:09 PM Bob Stewart wrote: > If you can touch the heat sink for 2 seconds, you're made of sterner stuff > than I am! They run very hot. It's a

Re: [time-nuts] Anyone (ideally in the UK) got a spare rotary knob for the 5370B TI counter?

A knob? Sounds like a good use for a 3D printer. ___ 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] Anyone (ideally in the UK) got a spare rotary knob for the 5370B TI counter?

If you can touch the heat sink for 2 seconds, you're made of sterner stuff than I am!  They run very hot.  It's a good idea to get a GPIB extender so your GPIB cable can clear the heat sink.  Somebody, can't remember who, worked up a nice looking conversion to a pair of switching supplies.  I

[time-nuts] Anyone (ideally in the UK) got a spare rotary knob for the 5370B TI counter?

I forgot to mention... I still have some 3-board extender card kits for the 5370's. Two boards are used to extend one of the main cards. The other fits the front panel board (and one of the other minor boards in the machine). Contact me off list if needed...

[time-nuts] Anyone (ideally in the UK) got a spare rotary knob for the 5370B TI counter?

I don't have a knob, but something that fits should be easy to find. One warning... some of the pots have plastic shafts that can be brittle. They can shear off either due to accident, turning too hard against the stops, or just old age. I seem to remember that one of them has a switch on

Re: [time-nuts] A Leap Second is coming

The leap second warning is present in the PTB clock too (Europe): On Fri, Dec 30, 2016 at 8:49 PM, Nick Sayer via time-nuts wrote: > I'm going to definitely observe my GPS clock to check its behavior. It > *should* repeat second zero (in my case of 4PM

Re: [time-nuts] Configuring LH5 for use with an HP 58503A

Hi Mark, Thanks for the advice-it did the trick! Regards, Stan Heather wants the device to be in half-duplex mode where it does not echo the serial port characters. Unfortunately in version 5 the command that it sends to turn echo off does not work on all receivers. It is fixed in

[time-nuts] Anyone (ideally in the UK) got a spare rotary knob for the 5370B TI counter?

I bought a 5370B TI counter which arrived today. It needs a bit of TLC, but nothing too bad. But one of the rotary knobs is incomplete. Does anyone have a spare knob? Contact me off list if you do. I had one of these things about 10 years ago. I have forgotten how to drive it. It is running

Re: [time-nuts] Measuring sidereal/solar time?

HI > On Dec 30, 2016, at 4:53 PM, Chris Albertson > wrote: > > Yes, the below is basically correct. But you save a ton of time and > get better results if you simply bolt the telescope down to the Earth > so that it can't move at all. The aim point just needs to

[time-nuts] HP5062C Chassis available

Hi, I have Seven HP5062C chassis collected over the years. Not sure how many tubes are installed (I can check) or their condition. I'm pretty sure most of the quartz oscillators are missing but I see two sitting by the pile. Might be a very few modules missing. Most of the top and bottom covers

Re: [time-nuts] Measuring sidereal/solar time?

Yes, the below is basically correct. But you save a ton of time and get better results if you simply bolt the telescope down to the Earth so that it can't move at all. The aim point just needs to be "close" and then later you determine where it is aimed.If you are only measuring period you

Re: [time-nuts] Measuring sidereal/solar time?

On Fri, Dec 30, 2016 at 2:42 AM, Attila Kinali wrote: > On Fri, 30 Dec 2016 10:59:03 +0200 > Anders Wallin wrote: > >> out of curiosity, are there any amateur/semi-pro experiments that can >> measure the length of the solar or sidereal day to

Re: [time-nuts] Measuring sidereal/solar time? Re: A Leap Second is coming

To improve the accuracy, I would integrate several measurements. There is no reason a sampled measurement at only one time needs to be made. On Fri, 30 Dec 2016 09:18:17 -0800, you wrote: >Hi Anders: > >That's something I've thought about for decades using an optical system. A >few years ago

Re: [time-nuts] Measuring sidereal/solar time? Re: A Leap Second is coming

Hi: Maybe this could be done with GPS or higher frequencies so the angular resolution would be better? -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html The lesser of evils is still evil. Original Message Brooke, The

Re: [time-nuts] A Leap Second is coming

I'm going to definitely observe my GPS clock to check its behavior. It *should* repeat second zero (in my case of 4PM PST). Not the most exactingly accurate depiction, but it's the best I can do with the architecture. Sent from my iPhone > On Dec 29, 2016, at 12:22 AM, David J Taylor

Re: [time-nuts] Measuring sidereal/solar time? Re: A Leap Second is coming

On 12/30/16 9:53 AM, Ilia Platone wrote: Brooke, The problem in radio ground observation can be resolution accuracy, but there's also a good transmission into far infrared wavelengths, which could require smaller dishes to get stellar images. The problem of far IR is the cost of right

[time-nuts] Heather V5 Holdover

If you started Heather and it shows a holdover time in GREEN, that means that the receiver's last holdover event was 51 seconds long. A holdover time in YELLOW, means that a 51 second holdover occurred while while Heather was running. A RED value means the receiver is currently in

Re: [time-nuts] HP Z3801 RB fun

paul wrote: The 10811 is far more difficult to pin down as several articles from TVB and others say the 10811 actually has a wider control range then the standard. Something like 10 Hz over 10V. Traditional is 1 Hz over 10 V. But as I say seems to be different answers depending on what you

[time-nuts] Mystery hp Oven UPDATE

Back in June I picked up the mystery oven assy that turned out to be the oscillator assy. of an HP 106A. Since then I have repaired it and another 106B oscillator assy for a friend. My oscillators main problem was that one of the inner oven windings was open. Just for testing I installed an array

[time-nuts] HP Z3801 RB fun

If you have a Thunderbolt and have it configured for an external oscillator, Lady Heathers' "" autotune command will determine and display the oscillator EFC sensitivity. It works by setting the DAC voltage a few millivolts high, measuring the frequency, setting the EFC a few millivolts

[time-nuts] Configuring LH5 for use with an HP 58503A

Heather wants the device to be in half-duplex mode where it does not echo the serial port characters. Unfortunately in version 5 the command that it sends to turn echo off does not work on all receivers. It is fixed in the next version. Right now, try starting heather with the /rx5 /bt

Re: [time-nuts] Measuring sidereal/solar time? Re: A Leap Second is coming

Brooke, The problem in radio ground observation can be resolution accuracy, but there's also a good transmission into far infrared wavelengths, which could require smaller dishes to get stellar images. The problem of far IR is the cost of right filters/sensor, which are a bit difficult to

Re: [time-nuts] Measuring sidereal/solar time? Re: A Leap Second is coming

Hi Anders: That's something I've thought about for decades using an optical system. A few years ago I looked at it again and found that astronomical "seeing" limits the accuracy. So the accuracy achieved by a spaceborne "Stellar compass" will be much better than a ground based observation.

[time-nuts] Configuring LH5 for use with an HP 58503A

I just resurrected an HP 58503A and have been using it successfully for the last few days with the GPSCon program. I would prefer to use Lady Heather, but can't seem to get it configured properly. My system is a Windows 10 PC with a USB to serial cable at COM3. The serial protocol on the 58503A is

Re: [time-nuts] HP Z3801 RB fun

Magnus Good afternoon. I am having a hard time following this. Conflicting data I believe.. Using the FRS-C because its the clearest. On page 3-14 it says +/- 1E-9 for 5V (5V is later in the book) Wouldn't that be 2E-9th for 5V? The 10811 is far more difficult to pin down as several articles from

Re: [time-nuts] HP Z3801 RB fun

I think the numbers given for 10811 sensitivity was grossly incorrect from the source I had, so it should be +/- 1E-6 for +/- 5V, thus giving 2E-6 over 10V thus giving a sensitivity of 2E-7/V. Compare to 4E-10/V fro the FRS-C and just redo the work. I thought the numbers where funny but too

Re: [time-nuts] Measuring sidereal/solar time? Re: A Leap Second is coming

I don't think we could call it "amateur/semi-pro" but the millisecond pulsar J0437-4715 would be perfect for this. Bright and precise. Only for southern hemisphere people though. :-) Jim Palfreyman On 30 December 2016 at 19:59, Anders Wallin wrote: > out of

Re: [time-nuts] FPGA SDR? (GnuRadio related)

On Fri, 30 Dec 2016 11:45:06 + Ilia Platone wrote: > By the way, I read about various Software Defined Radio projects and got > interested on this. In past I designed a 30MHz SAR ADC/DAC board using > an FPGA, and wanted to implement this into an SDR project. This is

[time-nuts] FPGA SDR? (GnuRadio related)

I got an old valve radio, an Italian Wundercart FM610, not really The radio, but I like it because it can receive MW and SW bands in AM modulation :), and FM at 88/110MHz of course. an 82-years old electronic friend helped me to get it working and I'm so happy for this. By the way, I read

Re: [time-nuts] Measuring sidereal/solar time?

Bruce, I think that you refer on prjects like Astrometry plate solving. I think one should got a reference to get a time reference instead of scope "pointing" reference, so, once one's got local coordinates in encoder positions, for example the values of the north pole with an alt/az

Re: [time-nuts] Measuring sidereal/solar time?

att...@kinali.ch said: > After that, it's just some simple math of calculating the difference between > the position of the stars and where you would have expecteded them at the > time when the picture has been taken. You will probably have to correct for the distortion of the lens. That is a

Re: [time-nuts] Measuring sidereal/solar time?

Another solution from ground can be radio observation using a precise interferometer: radio wavelengths are transparent to the earth atmosphere and there are various references like sun during day, and (if antennas are sensible) bright pulsars and other radio sources during night. Best

Re: [time-nuts] Measuring sidereal/solar time?

Attila Lookup "Stellar compass" as used for determining space probe attitude.Can also be used to determine the direction of the centre of an image of a field of bright stars.Subarcsecond accuracy is fairly routine.Pattern recognition techniques combined with measures of the relative brightness

Re: [time-nuts] Measuring sidereal/solar time?

On Fri, 30 Dec 2016 10:59:03 +0200 Anders Wallin wrote: > out of curiosity, are there any amateur/semi-pro experiments that can > measure the length of the solar or sidereal day to sub-millisecond > resolution? > To reproduce data like this: >

[time-nuts] Heather V5 Holdover

I just installed the new version of Heather, she's saying "Holdover: 51 secs" what's she trying to tell me please? Dave ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and

[time-nuts] Measuring sidereal/solar time? Re: A Leap Second is coming

out of curiosity, are there any amateur/semi-pro experiments that can measure the length of the solar or sidereal day to sub-millisecond resolution? To reproduce data like this: https://upload.wikimedia.org/wikipedia/commons/5/5b/Deviation_of_day_length_from_SI_day.svg Something in the sky that