[time-nuts] Z3805 PPS on comm port?

[John Ackermann N8UR]

I'm replacing a dead Z3801 with a less-dead Z3805 (the Samsung labeled, 
2 each 10 MHz and PPS BNCs, two DB25s).


Has anyone looked into whether that version of the 3805 has a PPS signal 
on the DB25, or a mod to put it there?  I've done some Googling and most 
of the discussion of the Z3805 seems to have been tracking down the 
various versions and not much on using it for NTP.  I can use one of the 
BNC PPSs if necessary, but a signal on the serial cable would be more 
convenient.


Thanks!
John
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[time-nuts] Re: QM10 Quartz chronometer

[Andy Talbot]

Some years ago, before we had locked LOs for transverters, the Am.
Microwave community used clip-on crystal heaters.  These were a PTC
thermistor with a turnover around 35 - 40C.   They were usually used on
5th or 7th overtone crystals around 100MHz  designed for 20C operation, so
weren't ideal, but could maintain a crystal more on frequency that just
open to the the air temp.
Perhaps used on a watch crystal thay would work more effectively.

Not sure where you'd get them from now, though.

Andy
www.g4jnt.com



On Fri, 26 Nov 2021 at 16:46, David G. McGaw 
wrote:

> But not in a chronometer.  They usually use something in the MHz range.
>
> 32kHz crystals are not very stable over temperature.  Watches rely on
> you wearing it for much of the day, keeping it at a nearly constant
> temperature and putting it on your bed stand at night, also presumably
> fairly constant.  Unfortunately they have been adopted for computer Real
> Time Clocks, which is why most computers do not keep very good time.
>
> David N1HAC
>
> On 11/26/21 9:14 AM, Scott McGrath wrote:
> > Usually in analog quartz clocks oscillator frequency is around 32khz
> >
> > Content by Scott
> > Typos by Siri
> >
> > On Nov 26, 2021, at 9:09 AM, Peter Torry via time-nuts <
> time-nuts@lists.febo.com> wrote:
> >
> > Hello list,
> >
> > I am restoring a Seiko Quartz QM10 Marine Chronometer that is currently
> inoperative. Preliminary investigations would indicate that the oscillator
> (TO5 header) isn't functioning therefore I am seeking any information as to
> its nominal frequency and whether it is just a crystal or an oscillator. I
> can follow the cmos dividers OK but a schematic diagram would be most
> useful.
> >
> > Any help or pointers much appreciated.
> >
> > Kind regards
> >
> > Peter   UK
> > ___
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[time-nuts] Re: QM10 Quartz chronometer

[David G. McGaw]

But not in a chronometer.  They usually use something in the MHz range.

32kHz crystals are not very stable over temperature.  Watches rely on 
you wearing it for much of the day, keeping it at a nearly constant 
temperature and putting it on your bed stand at night, also presumably 
fairly constant.  Unfortunately they have been adopted for computer Real 
Time Clocks, which is why most computers do not keep very good time.


David N1HAC

On 11/26/21 9:14 AM, Scott McGrath wrote:

Usually in analog quartz clocks oscillator frequency is around 32khz

Content by Scott
Typos by Siri

On Nov 26, 2021, at 9:09 AM, Peter Torry via time-nuts 
 wrote:

Hello list,

I am restoring a Seiko Quartz QM10 Marine Chronometer that is currently 
inoperative. Preliminary investigations would indicate that the oscillator (TO5 
header) isn't functioning therefore I am seeking any information as to its 
nominal frequency and whether it is just a crystal or an oscillator. I can 
follow the cmos dividers OK but a schematic diagram would be most useful.

Any help or pointers much appreciated.

Kind regards

Peter   UK
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[time-nuts] Re: HP 5065A, no 2nd harmonic.

[paul swed]

Jared
I took a look at the manual and if you inject 137 hz at .5 Vpp through a 10
Mohm R  thats in a sheild into A7j1 you will see .9 Vpp at TP2 and some
large signal upto 16 Vpp at Yellow out. That would say the A7 module is
good. It looks like the 2 ICs are lm741 class opamps if they happened to be
bad.
Regards
Paul
WB8TSL

On Wed, Nov 24, 2021 at 8:36 AM Jared Cabot via time-nuts <
time-nuts@lists.febo.com> wrote:

> Hi,
>
> Ok, I managed to get a moment to do a few tests. I'll try to answer the
> questions so far, sorry if I miss something out.
>
> For test equipment, I have the following gear of possible use:
> - HP 5335A 200MHz Universal Counter with 1.3GHz option
> - Leo Bodnar GPS Reference
> - HP 34461A Multimeter, just calibrated.
> - Tek TDS748C 1GHz Scope
> - Multiple HP E361xA Power supplies
> - 3325A Function Gen (All options)
> - Many other bits of gear too, including a billion TM500 modules and
> mainframes etc.
>
> On the 5065A front, I have replaced the resistors in the RVFR with
> Mil-spec Vishay RN55, RN60 and RN65 series parts, cleaned the glass
> elements and added a 100 deg.C thermostat to prevent over temperature
> events.
> I have replaced all the wet tantalum capacitors in the entire unit with
> United Chemicon KYB 220uF, 63V capacitors (10,000 hour rated), bypassed
> with C0G/NP0 0.1uF MLCC ceramic caps, there was no PCB damage, but two tant
> caps had just started leaking, luckily not reaching the PCB's.
> I added heat sinks to the two diodes on the A2 board and replaced the RIFA
> mains filter cap too. The 3 big mains filter capacitors tested well within
> spec, with leakage down around 10uA.
>
> - On A8 Pin9, I get 137KHz, 174mV P-P
>
> - A7 TP2 shows me random low amplitude noise
>
> - A3 TP2 I see 5.38VDC
>
> My serial number is 2432A01344 and I have the 10811-60109 OCXO (and no
> options fitted, so the chassis is clean of battery corrosion).
>
>
> Thanks all for the help!
> Jared___
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[time-nuts] Re: QM10 Quartz chronometer

[Don Couch]

I have two of these. They are very nice precision chronometers. If I remember 
correctly, the frequency is 4194304. The oscillator is a TCXO usually in a 
small round 8-legged can.  I have never seen a bad one. The most common problem 
is the backup battery. If it is still there, it is very old and often shorted. 
There is a diode in series so if the battery is shorted, it does no harm, but I 
have seen the diode shorted as well. I do not have schematics, but you can 
trace the battery circuit.

Don Couch

Sent from Mail for Windows


From: Scott McGrath 
Sent: Friday, November 26, 2021 7:14:04 AM
To: Discussion of precise time and frequency measurement 

Subject: [time-nuts] Re: QM10 Quartz chronometer

Usually in analog quartz clocks oscillator frequency is around 32khz

Content by Scott
Typos by Siri

On Nov 26, 2021, at 9:09 AM, Peter Torry via time-nuts 
 wrote:

Hello list,

I am restoring a Seiko Quartz QM10 Marine Chronometer that is currently 
inoperative. Preliminary investigations would indicate that the oscillator (TO5 
header) isn't functioning therefore I am seeking any information as to its 
nominal frequency and whether it is just a crystal or an oscillator. I can 
follow the cmos dividers OK but a schematic diagram would be most useful.

Any help or pointers much appreciated.

Kind regards

Peter   UK
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[time-nuts] Re: QM10 Quartz chronometer

[per...@tellink.net]

Check this link: 
https://www.watchuseek.com/threads/seiko-marine-chronometer-qm-10.4913/
It indicates that the QM-10 used a 4.19MHz crystal.

John

- Original Message -
From: "Peter Torry via time-nuts" 
To: time-nuts@lists.febo.com
Cc: "Peter Torry" 
Sent: Friday, November 26, 2021 9:09:07 AM
Subject: [time-nuts] QM10 Quartz chronometer

Hello list,

I am restoring a Seiko Quartz QM10 Marine Chronometer that is currently 
inoperative. Preliminary investigations would indicate that the 
oscillator (TO5 header) isn't functioning therefore I am seeking any 
information as to its nominal frequency and whether it is just a crystal 
or an oscillator. I can follow the cmos dividers OK but a schematic 
diagram would be most useful.

Any help or pointers much appreciated.

Kind regards

Peter   UK
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[time-nuts] Re: QM10 Quartz chronometer

[Scott McGrath]

Usually in analog quartz clocks oscillator frequency is around 32khz

Content by Scott
Typos by Siri

On Nov 26, 2021, at 9:09 AM, Peter Torry via time-nuts 
 wrote:

Hello list,

I am restoring a Seiko Quartz QM10 Marine Chronometer that is currently 
inoperative. Preliminary investigations would indicate that the oscillator (TO5 
header) isn't functioning therefore I am seeking any information as to its 
nominal frequency and whether it is just a crystal or an oscillator. I can 
follow the cmos dividers OK but a schematic diagram would be most useful.

Any help or pointers much appreciated.

Kind regards

Peter   UK
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[time-nuts] QM10 Quartz chronometer

[Peter Torry via time-nuts]

Hello list,

I am restoring a Seiko Quartz QM10 Marine Chronometer that is currently 
inoperative. Preliminary investigations would indicate that the 
oscillator (TO5 header) isn't functioning therefore I am seeking any 
information as to its nominal frequency and whether it is just a crystal 
or an oscillator. I can follow the cmos dividers OK but a schematic 
diagram would be most useful.


Any help or pointers much appreciated.

Kind regards

Peter   UK
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