Re: [time-nuts] J06 HP-59992A time interval calibrator for HP-531xx counters

[Francesco Messineo]

On Sun, Jul 9, 2017 at 2:15 AM, Mark Sims  wrote:

>
> So far my design is tending towards:  10MHz ref input -> Minicircuits doubler 
> -> Wenzel squarer -> 74AC74 divider -> 74AC04 buffer -> level shifter.  The 
> doubler/divider might not be needed,  but I think it will give a more 
> symmetric output.  I might include a space for a 10 MHz TTL oscillator for 
> non time-nut users... hopefully it might be stable enough over the short time 
> interval for a cal measurement cycle.


once upon a time, I was experimenting with digital signals to derive
stable RF transverter
LOs. I've "found" that feeding a XOR gate with a signal and his
replica delayed by 2 inverters
did result in a crude frequency doubler (well it's rather an edge
detector). Since I was going to use the double frequency just to drive
a divider by two, the actual duty cycle out of the doubler didn't
matter.

HTH
Frank
___
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] OT: Eagle PC CAD now Autodesk, $500/year

[Francesco Messineo]

On Fri, Jan 20, 2017 at 4:52 AM, Richard (Rick) Karlquist
 wrote:
> Off topic, but probably a lot of disgrunted Eagle users on this list.
> Its official, you will now have to pay $500 per year for a
> professional license from Autodesk.  The spin meistering of the
> announcement would make George Orwell proud.  I don't see any way they
> can keep me from just using the license I currently own, at least
> on the OS's it supports.  (Parenthetically, like many users, I
> am also digging in my heels in terms of staying at Windows 7).
>
> Still, the question arises:  are there any affordable alternatives?

I'm using KiCad since a few years. There're conversion tools from the
eagle libraries to obtain
both schematic libs and footprints to be used on KiCad. There're also
quite a few native libraries. Overall I would never look for anything
else. But I'm not a professional user, so my time is kind of free.

73
Frank IZ8DWF
___
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] HP 59309A Clock runs, sets via GPIB, but no GPIB output?

[Francesco Messineo]

1818-2295A dump has been uploaded to ko4bb site, probably there's need
to be moved in the right place before it's available.

On Mon, Oct 10, 2016 at 9:32 AM, Francesco Messineo
<francesco.messi...@gmail.com> wrote:
> Hi Dave,
> right, once I find the dumps, I'll upload them.
> thanks
> Frank IZ8DWF
>
> On Mon, Oct 10, 2016 at 9:24 AM, Artek Manuals <manu...@artekmanuals.com> 
> wrote:
>> Frank
>>
>> One of the best places to store ROM dumps for easy access by everyon is
>> KO4BB.com
>>
>> Dave
>> NR1DX
>> dit dit
>>
>> On 10/10/2016 3:20 AM, Francesco Messineo wrote:
>>>
>>> I have a dump of the 1818-2295A somewhere, it should be archived in
>>> one of my backups. I also made a replacement with a board having 2 x
>>> 28C64 SO-28 eeproms and it worked in my 59309A as far as I could test
>>> it. However these eeproms present many glitches on the outputs during
>>> address toggling, so it's way better to use a suitable CPLD after
>>> recovering the equations (I'm a bit stuck on this project due to lack
>>> of time...).
>>> If someone needs the dump, just let me know and I'll dig it out.
>>> HTH
>>> Frank IZ8DWF
>>
>>
>>
>> --
>> Dave
>> manu...@artekmanuals.com
>> www.ArtekManuals.com
>> ___
>> 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.
___
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] HP 59309A Clock runs, sets via GPIB, but no GPIB output?

[Francesco Messineo]

Hi Bob,
I will send you my dump, but you have to wait at least until tomorrow
evening. I'm not near my backups today.
I can confirm that 2 x 28C64 (I used ST parts, so if you can scope
your Atmels for glitch, I would be very much curious to see if they've
the same problem) worked in my 59309A, but for example the same
replacement failed in the 5328A HPIB option state machine (and worked
in the main 5328A state machine...) so it's probably a matter of luck
on the timings and the glitches.
I have already planned a CPLD replacement for these small ROMs, but
really it needs time
to get back the dumps and running each output into the program that
reconstruct the equation, then programming all the 16 equation into a
suitable CPLD, make the PCB, program it and so on...


On Mon, Oct 10, 2016 at 9:46 AM, Bob <b...@marinelli.org> wrote:
> Hi Francesco,
>
> That's wonderful, I hadn't dreamt that anyone has dumped out that ROM.  If 
> you can find your copy of your good 1818-2295A ROM it would let us avoid 
> trying to fix the bit rot in the one I was able to read, especially as we 
> don't know if the 1818-2295A exactly matches the tables in the user manual.
>
> Just this afternoon I ordered a couple Atmel AT28C64 EEPROMs and a 28 pin DIP 
> header. When the parts arrive I'll try replacing U2 with them.  The original 
> part is 5v signals and the modern parts can ignore the +12 and -2 pins, and 
> of course are erasable.  As the Teensy++ easily reads the HP part, and will 
> read the pin compatible new replacement, it should be possible to have the 
> replacement match the bits in the manual.  At least I'll not have a stuck 
> LOAD pin :)
>
> Agreed about modern fast parts glitching but watching the logic analyzer, it 
> seems the 59309A samples the ROM in a very relaxed manner using the TP2 slow 
> clock, maybe we can get by without a CPLD.
>
> I'll report back after writing and testing EEPROMs*.  Knowing that you had 
> success is a great encouragement.
>
> Hi Paul and Don,
>
> Thank you both *very* much for checking the U2 part number on your clocks.  
> That you both see 1818-2295A is terrific, it means that the ROM version in 
> this clock matches its serial prefix.
>
> Cheers,
>
> Bob
> N2CJL
>
> * The two main state machines have 8 and 53 states, and with logic analyzer 
> watching the EEPROM it should be possible to follow along.  It is a nice 
> little computer with constant time instructions, 64 bits of RAM.  Each 
> instruction contains a conditional qualifier along with the next address, 
> very 1960s.
>
>
>
>> On Oct 10, 2016, at 12:32 AM, Francesco Messineo 
>> <francesco.messi...@gmail.com> wrote:
>>
>> Hi Dave,
>> right, once I find the dumps, I'll upload them.
>> thanks
>> Frank IZ8DWF
>>
>> On Mon, Oct 10, 2016 at 9:24 AM, Artek Manuals <manu...@artekmanuals.com> 
>> wrote:
>>> Frank
>>>
>>> One of the best places to store ROM dumps for easy access by everyon is
>>> KO4BB.com
>>>
>>> Dave
>>> NR1DX
>>> dit dit
>>>
>>> On 10/10/2016 3:20 AM, Francesco Messineo wrote:
>>>>
>>>> I have a dump of the 1818-2295A somewhere, it should be archived in
>>>> one of my backups. I also made a replacement with a board having 2 x
>>>> 28C64 SO-28 eeproms and it worked in my 59309A as far as I could test
>>>> it. However these eeproms present many glitches on the outputs during
>>>> address toggling, so it's way better to use a suitable CPLD after
>>>> recovering the equations (I'm a bit stuck on this project due to lack
>>>> of time...).
>>>> If someone needs the dump, just let me know and I'll dig it out.
>>>> HTH
>>>> Frank IZ8DWF
>>>
>>> --
>>> Dave
>>> manu...@artekmanuals.com
>>> www.ArtekManuals.com
>
> ___
> 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.
___
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] HP 59309A Clock runs, sets via GPIB, but no GPIB output?

[Francesco Messineo]

Hi Dave,
right, once I find the dumps, I'll upload them.
thanks
Frank IZ8DWF

On Mon, Oct 10, 2016 at 9:24 AM, Artek Manuals <manu...@artekmanuals.com> wrote:
> Frank
>
> One of the best places to store ROM dumps for easy access by everyon is
> KO4BB.com
>
> Dave
> NR1DX
> dit dit
>
> On 10/10/2016 3:20 AM, Francesco Messineo wrote:
>>
>> I have a dump of the 1818-2295A somewhere, it should be archived in
>> one of my backups. I also made a replacement with a board having 2 x
>> 28C64 SO-28 eeproms and it worked in my 59309A as far as I could test
>> it. However these eeproms present many glitches on the outputs during
>> address toggling, so it's way better to use a suitable CPLD after
>> recovering the equations (I'm a bit stuck on this project due to lack
>> of time...).
>> If someone needs the dump, just let me know and I'll dig it out.
>> HTH
>> Frank IZ8DWF
>
>
>
> --
> Dave
> manu...@artekmanuals.com
> www.ArtekManuals.com
> ___
> 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.
___
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] HP 59309A Clock runs, sets via GPIB, but no GPIB output?

[Francesco Messineo]

I have a dump of the 1818-2295A somewhere, it should be archived in
one of my backups. I also made a replacement with a board having 2 x
28C64 SO-28 eeproms and it worked in my 59309A as far as I could test
it. However these eeproms present many glitches on the outputs during
address toggling, so it's way better to use a suitable CPLD after
recovering the equations (I'm a bit stuck on this project due to lack
of time...).
If someone needs the dump, just let me know and I'll dig it out.
HTH
Frank IZ8DWF

On Mon, Oct 10, 2016 at 5:34 AM, Paul Berger  wrote:
> Bob,
>
> I just looked at the clock I am not using and it is 1818-2295A, it is not
> convenient for me to check the other one as it is running and in a place
> where I would have to disconnect it to get it out.   I could dump this ROM
> for you but it may take me a few days as I have other things on the go right
> now.
>
> Paul.
>
> On 2016-10-09 10:48 PM, Bob wrote:
>>
>> Hi Tom & Paul,
>>
>> Some progress with the HP 59309A clock debug.  Built a ROM reader
>> (Teensy++, a 28 pin WW socket, jumpers) and read out the HP 59309A U2 ROM.
>>
>> Compared the user manual to my readings, found three stuck output bits out
>> of sixteen, and another few dozen assorted differences out of the 4096 ROM
>> bits.
>>
>> Also, while moving U2 to the reader socket I noticed that the chip is
>> stamped 1818-2295A 2335 vs. the schematic which states U2 is a 1818-2193.
>> Perhaps the U2 state machine was updated?
>>
>> The O1 (part of Next Address) bit, O9 (LOAD) bit and O11 (Rout) bit always
>> read 0.  Together those stuck-at-0 bits compose the vast majority of the bit
>> differences.  LOAD being always zero explains why I don't see data written
>> into the RAM when watching with a logic analyzer.
>>
>> I'm 99% sure there is at least some bit rot, in particular there is a long
>> unused block at the end of the Talk Enable = 1 table, where all addresses
>> should match, and in the middle of that range there are just a few wrong
>> bits.
>>
>> A small number of differences exist in other Next Address and Next
>> Qualifier columns, but there are only a few, not easy to tell if they are
>> just changes to the state machine or more bit rot.
>>
>> Digging further, the serial number prefix 2510A is much newer than the
>> 1632A prefix mentioned in the manual I'm looking at, so there could be
>> differences in the schematic.  Not clear if HP change pages up to 2510A
>> exist, I've not found them so far.
>>
>> At this point, I can think of a few paths to take...
>>
>> a) Leave it alone, still works fine as a desk clock, but useless for
>> reading TOD via HP-IB.
>>
>> b) Build a little adapter board and replace U2 with a self-programmed 16
>> bit EPROM or a pair of 8 bit EPROMs.  I could use the code in the manual,
>> buzz out the circuit to validate the schematic, and (if needed) reverse
>> engineer the state machine.
>>
>> Tom and/or Paul, would you consider lifting the cover off your clock (just
>> 2 screws in the back) and peeking at the part number on your U2 chips?
>> That's the 28 pin ceramic ROM in the socket on the A5 board which is the one
>> at the far left looking from the front.  The ROM is at the top of the board
>> and should be visible without touching anything.
>>
>> If someone happens to have a ROM stamped 1818-2295A 2335, it would of
>> course be great to capture the bits, to remove the remaining guesswork in
>> creating a replacement image.  Naturally, I checked the ROMs on Didier's
>> site, but didn't see any for the 59309A.
>>
>> In conclusion, reading the U2 ROM shows three stuck bits, including LOAD,
>> which explains what I saw on the logic analyzer.
>>
>> Cheers,
>>
>> Bob
>>
>>
>
> ___
> 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.
___
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] The Symmetricom GPS Antenna's

[Francesco Messineo]

Same here,
shipping costs to Italy were quoted at $65, no joy.
I'll try to make some US friend buy one and re-send with cheaper
method, if possible.


On Fri, Oct 2, 2015 at 7:36 PM, Roy Phillips  wrote:
> For we Europeans, British in my case, the Symmetricom GPS antennas are very 
> good buy – but the addition of US $60.00 for the shipping makes them rather 
> expensive ! – plus taxes ..
> Roy
>
> ___
> 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.
___
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] HP5328A HP5328B

[Francesco Messineo]

On Thu, Apr 23, 2015 at 9:13 PM, Charles Steinmetz
csteinm...@yandex.com wrote:
 Magnus wrote:

 Would be fun to have a GPIB interface in the HP5328A


 ???  I have 6 or 7 of these, and they all have HPIB interfaces.  It was
 option 011 for the 5328A.  I believe all 5328Bs had HPIB as standard.  Here
 is a link to the 5328A Opt 011 op/service manual:

 http://www.keysight.com/main/redirector.jspx?action=refcname=EDITORIALckey=805967lc=engcc=USnfr=-536900193.536897943.00

 I'm not sure I've ever seen a 5328 (A or B) that didn't have HPIB.  (It may
 be worth noting that ex-US military 5328As are very common here in the US,
 and I believe all of those had HPIB.)  The ex-military counters have a
 number of differences from the commercial versions.

5328A without HPIB indeed do exist. I've seen a few of them, these are
the no-options instruments usually.

Frank IZ8DWF
___
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] PPS delay on rockwell

[Francesco Messineo]

On Sun, Feb 15, 2015 at 10:34 PM, Hal Murray hmur...@megapathdsl.net wrote:

 francesco.messi...@gmail.com said:
 I measured the PPS output with an HP-5328B, PPS of the thunderbolt as start,
 rising edge, rockwell PPS as stop, rising edge. The delay is 406.3 ms +/- 30
 uS.

 Are those numbers normal for a rockwell chipset? Any idea why the two PPS
 are so far apart? PPS offset on the thunderbolt is set to 0.

 Do you have a scope?  What's the width of the Rockwell PPS?

yes, I have looked at the PPS shape, it's a 20ms positive pulse


 Are you triggering on the correct edge?  Is there an inverter in there
 someplace?

 I would try all 4 combinations of rising/falling edges and see if any of them
 match cleanly.  That could happen if the Rockwell PPS is 500 ms wide.

I tried all 4 combinations (besides, the thunderbolt is set for
positive PPS), the positive thunderbolt to positive rockwell is the
closest of all at 406 ms.
I can only suspect it was unlocked, but I need to setup all the test
in another place closer to the window, since I don't have a splitter
to use the same antenna of the thunderbolt.

Thanks
Frank
___
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.

[time-nuts] PPS delay on rockwell

[Francesco Messineo]

Hi all,

I'm testing a custom (and unknown to me) GPS board I had for free some
years ago. It has a 10 KHz output and 1 PPS output.
Using a thunderbolt as reference, 10 KHz output is abut 13 mHz higher
(10 MHz output of the thunderbolt is the time base of the counter,
HP-5386A).
I measured the PPS output with an HP-5328B, PPS of the thunderbolt as
start, rising edge, rockwell PPS as stop, rising edge. The delay is
406.3 ms +/- 30 uS.
Are those numbers normal for a rockwell chipset? Any idea why the two
PPS are so far apart? PPS offset on the thunderbolt is set to 0.

Thanks
Frank
___
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] tyco electronics A1025

[Francesco Messineo]

On Mon, Dec 15, 2014 at 9:09 AM, Brian Inglis
brian.ing...@systematicsw.ab.ca wrote:
 On 2014-12-14 10:29, Francesco Messineo wrote:

 The A1029, which is a newer model, has indeed a PPS output and I've
 been able to find a datasheet for it but the pinout isn't anything
 like the A1025.
 I planned to reverse engineer the pinout, but I'd like at least not to
 be forced to try to guess the power pins. Maybe someone still has the
 data for this older module.


 One article mentions the A1029 as a drop in replacement for the A1025,
 as an early auto receiver with gyro and dead reckoning nav holdover,
 but that may refer to the complete module, and you may have just the GPS.

 The GPS could have provided PPS for DR nav, and some TE model specs offer
 TCXOs, which may also have been required for DR timing holdover, but may
 not have been part of the GPS.

 Those GPS seem to have been standard STMicroelectronics parts with firmware
 customization for functions and additions, and offered proprietary $PSTM
 NMEA sentences. If you can read off the STM part STA 2... (perhaps under
 a patch antenna) you may be able to search for more details.

I've found a couple of articles saying the A1025 indeed has PPS output
as I suspected. However, none of them reports any hint about the
pinout of this module.
The module itself is soldered on a small daughter board, so I can't
look on the other side for possible part numbers other than the tyco
electronics one.
The daughter board has some transistors, passives, a 74HC14 and a
small component, probably a power supply regulator that I can't
identify. It's a microchip part marked CS05351CK (CS0535 1CK in two
rows).
Reverse engineering is not progressing much also because of this
unknown microchip part.

Regards

Frank
___
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] tyco electronics A1025

[Francesco Messineo]

I reply to myself,

On Mon, Dec 15, 2014 at 2:41 PM, Francesco Messineo
francesco.messi...@gmail.com wrote:


 I've found a couple of articles saying the A1025 indeed has PPS output
 as I suspected. However, none of them reports any hint about the
 pinout of this module.
 The module itself is soldered on a small daughter board, so I can't
 look on the other side for possible part numbers other than the tyco
 electronics one.
 The daughter board has some transistors, passives, a 74HC14 and a
 small component, probably a power supply regulator that I can't
 identify. It's a microchip part marked CS05351CK (CS0535 1CK in two
 rows).

I identified this component, it's an MCP1700 LDO 3.3V  voltage
regulator in SOT-89 package.
So now I can power the board, connect an antenna and scope signals.

It should be easy now.

Best regards

Frank
___
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.

[time-nuts] tyco electronics A1025

[Francesco Messineo]

Hi all,
I've just found an old anti-theft system (I think) for cars . It has a tyco
electronics A1205 gps module.
I've been unable to find any information about this module, other than it
should be a 3.3V 12 channel GPS module with serial NMEA output.
Does anyone have any informations about it? Even a pinout would help. I'd
like to use it as a cheap NMEA receiver for a stratum 1 ntp server.
Thanks in advance.

Frank IZ8DWF
___
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] tyco electronics A1025

[Francesco Messineo]

On Sun, Dec 14, 2014 at 3:46 PM, Bob Camp kb...@n1k.org wrote:

 Hi

  On Dec 14, 2014, at 6:03 AM, Francesco Messineo 
  francesco.messi...@gmail.com wrote:
 
  Hi all,
  I've just found an old anti-theft system (I think) for cars . It has a tyco
  electronics A1205 gps module.
  I've been unable to find any information about this module, other than it
  should be a 3.3V 12 channel GPS module with serial NMEA output.
  Does anyone have any informations about it? Even a pinout would help. I'd
  like to use it as a cheap NMEA receiver for a stratum 1 ntp server.
  Thanks in advance.

 It’s unlikely that a consumer targeted GPS has a good dedicated PPS out of 
 it. Finding one that will do position hold is even less likely. You can get 
 modules that will do both for  $20 and have a documented interface.

that's not meant as a time nut stratum 1.
It's just a free gps module I would like to recycle as a needed
stratum 1 server for a small network.
Of course if I can find informations on it.
I know there're better options, but in this case anything would do.


Frank
___
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] tyco electronics A1025

[Francesco Messineo]

On Sun, Dec 14, 2014 at 6:12 PM, Bob Camp kb...@n1k.org wrote:


 It’s unlikely that a consumer targeted GPS has a good dedicated PPS out of 
 it. Finding one that will do position hold is even less likely. You can get 
 modules that will do both for  $20 and have a documented interface.

 that's not meant as a time nut stratum 1.
 It's just a free gps module I would like to recycle as a needed
 stratum 1 server for a small network.
 Of course if I can find informations on it.
 I know there're better options, but in this case anything would do.

 … and NTP is not a GPSDO or a Cs replacement.

 My guess is that there is no PPS out of the device. It would be very unusual 
 if there was. Finding the NEMA output pin should be possible with an 
 oscilloscope. At that point, a simple serial connection to the server is 
 about all you need. Bring up the NEMA driver and it is running. It is 
 unlikely that any further optimization would be possible, even with the 
 (maybe) 290 page data sheet on the part. I would not let the lack of a data 
 sheet stop you in this case. Hook up the output to a PC with a terminal 
 program and see what you get. The main problem would be if you need to find 
 the serial input pin to change what it puts out, hopefully you do not.



The A1029, which is a newer model, has indeed a PPS output and I've
been able to find a datasheet for it but the pinout isn't anything
like the A1025.
I planned to reverse engineer the pinout, but I'd like at least not to
be forced to try to guess the power pins. Maybe someone still has the
data for this older module.

Frank
___
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] Divide by five

[Francesco Messineo]

Sorry if I hijack the thread...

On Sat, Nov 8, 2014 at 5:20 AM, Said Jackson via time-nuts
time-nuts@febo.com wrote:
 Joe,

 This puppy can go to 166MHz over temp and has standard 100 mil pin spacing if 
 you put it into a socket: ATF16V8C

 I have not used PALs since 1992 but I used to be extremely fond of the 16R8 
 and 22V10 types back then.

 This is a 16V8 that will do your divider in no time:

 http://www.digikey.com/product-detail/en/ATF16V8C-5JX/ATF16V8C-5JX-ND/1027054

can anyone suggest a (cheap if possible) programmer and software for
these modern PLD?

Thanks and best regards
Frank  IZ8DWF
___
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] KO4BB.com

[Francesco Messineo]

On Sun, Sep 28, 2014 at 6:35 PM, Didier Juges shali...@gmail.com wrote:

 Thank you for your patience and your support.

thank to you for your service!
I'm a *nix system administrator since 20 years (well, my job would
turn 20 next year actually). So if you ever need any support, just
ask.

Frank
___
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.

[time-nuts] quartz oscillator injection locking

[Francesco Messineo]

Hi all,

what would be the best method to try injection locking a butler common
base crystal oscillator (see figure in
http://www.eska.dk/oscillator_data.htm for schematic)?
Any comment about close-in phase noise performance when adding
injection locking to such oscillators?
Thanks in advance for any hint.

Frank
___
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] Low cost GPS module for 100ns timestamping error

[Francesco Messineo]

On Sun, May 4, 2014 at 5:40 PM, Chris Albertson
albertson.ch...@gmail.com wrote:
 Looks like this is all you'd need for most timing projects.  Just add your
 favorite OCXO and some wire.

 The SPARC (not Spark) is actually a step up from ARM.  It was developed by
 Sun Microsystems (now Oracle) it is optimized for things like fast context
 switching, multi tasking and so on, all the things done by operating
 systems. The Sparc V8 does 128 bit floating point, (quad precision) I
 wonder if 200Kb RAM is enough to run an older version of SunOS?  (a BSD
 variant.)

In a previous life, I worked as Unix sysadmin at university. We had
several old Sun3 (motorola 68020 based) and a few Sparcstation based
on Sparc. The first SunOS I worked with was 4.1.1U1 and the last
4.1.4.
I remember even the 68020 were  a bit unhappy with 4Mbytes of RAM but
I can't recall if it was a kernel requirement or just the userland
stuff we needed to run on them.
Probably NetBSD can be a more recent and configurable option for
embedded sparcs.

best regards

Frank
___
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] Is this ocxo salvageable?

[Francesco Messineo]

On Wed, Apr 9, 2014 at 8:58 AM, David McQuate mcqu...@sonic.net wrote:
 The output looks differentiated, as would happen if the wire connecting the
 internal circuit to the output pin became open, leaving only a very small
 capacitance to couple the square wave out.

I agree, I had a similar problem on an oscilloscope input some time
ago. It was a cold solder joint.
It must definitely repairable as long as the shielding can be opened safely.

Regards
Frank  IZ8DWF


 Dave

 On 4/8/2014 11:46 PM, Chris Albertson wrote:

 My Bliley square wave 10MHz OCXO was working just fine for close to 30
 hours until a few hours ago.  Now it puts out a rather noisy waveform
 about
 one volt peak to peak.

 Two questions:
 (1) Are these things repairable, the metal can is soldered.

 (2) As you can see in the attached oscilloscope photo the OCXO still puts
 out a strong 10MHZ component.  What is the best way to filter this and
 recover a good 10MHZ square wave?

 In the linked photo, both channels are set to 1 volt per division.  The
 large sine wave is from a Trimble Thunderbolt and the smaller wave is from
 the failed ocxo  The EFC is left open (disconnected) and a you can see the
 frequency is spot on 10MHz.

 https://www.dropbox.com/s/0gy3yobd4myi4vp/waveform.jpg


 ___
 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.
___
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.

[time-nuts] Help OCXO ID

[Francesco Messineo]

Hello all,

does anyone know what's the OCXO (or else) in this picture?

http://www.electronicsurplus.it/open2b/var/catalog/images/1354/0-c26b2bc0-800.jpg

I'm trying to understand if it's something worth buying, but I can't
find any information on the site other than 5 MHz oven quartz
oscillator (and I'm not sure they exactly know even that).

Thanks in advance.

Frank IZ8DWF
___
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] Tboltmon and linux

[francesco messineo]

On Mon, Sep 2, 2013 at 12:23 AM, Paul Alfille paul.alfi...@gmail.com wrote:
 I want to report that tboltmon works well on linux under Wine.

 I'm running fedora 19, 64-bit (so the executable is wine64) and tboltmon
 version 2.6

 Getting a com port pointing to a USB serial adapter is it's own project, but
 quite doable.

getting a com port under wine is as easy as making a symbolic link
under ~/.wine/dosdevices
I have bound the com port even to remote serial ports brought via
network using the socat utility, Tboltmon and lady heather both worked
fine with remote serial ports too.

HTH
Frank
___
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.

[time-nuts] DCF77 phase modulation receiver

[francesco messineo]

Hi all,

has anyone tried to duplicate the following project:

http://www.marvellconsultants.com/DCF

Any comment?
Best regards

Frank

___
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] Cables dor 10 mHz

[francesco messineo]

On Tue, Jul 31, 2012 at 1:50 AM, Chuck Harris cfhar...@erols.com wrote:
 Chris Albertson wrote:
 ...   I wonder how many


 Or maybe more to the point, I wonder how many of us have installed
 10base5 cable, and done vampire taps?  I think I still have one of
 the tools around here somewhere... probably with my G-D wirewrap
 gun.


In my university years, I had a lot of fun (and a bit of money) with
10Base5 cabling and all the related stuff.
I still have some spare transceivers with vampire taps, brand new in
their boxes. The problem with 10Base5 was that someone overnight would
install his vampire tap on the yellow cable without telling us and
often pick an already assigned IP... that would start me on the find
the new tap game (300m of cable running on a couple of lab and
offices filled floors). Those years were fun indeed.

Frank  IZ8DWF

___
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.

[time-nuts] thunderbolt no UTC offset

[francesco messineo]

Hi all,

I just powered on again my trimble thunderbolt after some time without antenna.
All alarms are green but the obvious leap second pending. BUT: I can't
use UTC time as both tboltmon and lady heather display a No UTC
offset message. I don't remember having seen this in the past. What's
wrong with the thunderbolt now?

Many thanks in advance

Frank IZ8DWF

___
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] thunderbolt no UTC offset

[francesco messineo]

Hi Hal,


On 5/1/12, Hal Murray hmur...@megapathdsl.net wrote:

 francesco.messi...@gmail.com said:
 I just powered on again my trimble thunderbolt after some time without
 antenna. All alarms are green but the obvious leap second pending. BUT: I
 can't use UTC time as both tboltmon and lady heather display a No UTC
 offset message. I don't remember having seen this in the past. What's
 wrong
 with the thunderbolt now?

 How long has it been on?

 The UTC offset comes from the satellites.  I think it is only sent every
 hour.

yes indeed, it was ok after about 1 hour of the power up. Sorry but I
didn't remember I had ever waited so long for the UTC to come on.
I'm now plotting the signal strength vs AZ/EL map, I'll post the
result tomorrow so maybe someone can tell me how the new antenna is
working.

Thanks
Frank IZ8DWF

___
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] thunderbolt no UTC offset

[francesco messineo]

On 5/1/12, saidj...@aol.com saidj...@aol.com wrote:
 Incorrect, the UTC offset should be sent in the Almanac, the Almanac
 having a period of 12.5 minutes max. Not one hour. It should take no more
 than
 12.5 minutes to get the UTC offset when sats are properly being  received.

when I posted my original enquiry, the almanac alarm had turned
green since quite some time already, that's why I was wondering what
could be wrong.

Best regards

Frank

___
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.

[time-nuts] again on GPS antennas

[francesco messineo]

Hi all,

seeing this spec sheet:

http://www.saderet.co.uk/Admin/Datasheet/New%20antenna_spec.pdf

 I was wondering why these antennas have so different GPS bandwidth.
Does the BW  affect performance of a trimble thunderbolt for example?
Thanks in advance

Frank  IZ8DWF

___
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] What's the best way to double 10 MHz to 20 MHz ?

[francesco messineo]

On Fri, May 27, 2011 at 6:10 PM, Mark Spencer mspencer12...@yahoo.ca wrote:
 Imho phase noise is probably as important as long term stability in this 
 application.


for real and serious amateur radio dxing it's much more important the
phase noise and IMD3 performance of the RX rather than stability. Not
that stability doesn't matter, but I'd never trade not excellent PN
for stability.
Best regards

Frank IZ8DWF

___
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] Strange temperature peak

[francesco messineo]

Hi Alberto,

On Fri, May 27, 2011 at 8:45 PM, Alberto di Bene dib...@usa.net wrote:
 I left my Thunderbolt running with Lady Heather started. Returning after a
 few hours in the room,
 which is at a constant temperature (underground, no heating, no air
 conditioning), I found the
 following plot on the Lady Heather screen :

 http://www.sdradio.eu/images/ladyheather.gif


since the plot has a step jump, seems only a few tens mC, and then it
comes slowly back to the normal track, I'd rule out at least an
external temperature change: the thunderbolt can easily detect an hand
in its proximity even for a few seconds, but I don't remember ever
seen a step change.
Could be a firmware/sensor/communication error, but I'm not able to
explain why it comes back to normal slowly (but I'm sure there's a
firmware reason for that).

Frank IZ8DWF

___
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] Got 60HZ?

[francesco messineo]

Hello,

On Thu, Dec 9, 2010 at 5:13 AM, Michael Poulos poulo...@gmail.com wrote:
 Recently I bought a Efratom Ru frequency standard from eBay and a frequency
 divider chip that makes 1MHZ,100KHZ,25KHZ,10KHZ,100HZ and a 1HZ output.
 Today I thought of a way to make a nice 60HZ so you can use a mains-powered
 clock for the display (using amplifier and transformer wired backwards).
 But, now you'll need 60HZ. A European has it easy with 50HZ as you use a
 BASIC Stamp or Arduino to divide the 100HZ output. But for 60HZ I came up
 with a solution:

 You set up the Arduino to take the 10KHZ from the divider chip and program
 it to count off 83 pulses to flip an output. But wait! Unless you add a
 leap count every 3 flips of the output, it'll run fast. Assume at the
 start the Arduino output starts high then turns low:

 (83+83+84+83+83+84)*20 = 10,000 pulses = one second
 H__L__H__L__H__L

 Every output cycle and a half the voltage swing is a little over 1 percent
 longer because of the leap count. This means that the distortion adds a
 slight inaccuracy, not enough to upset New Year's revelers. But if you want
 a better 60HZ, try using the 100KHZ:

 (833+833+834+833+833+834)*20 = one second

 You see where this is going with leap counts. The ultimate of course is one
 really good Arduino and (after a hex inverter to amplify it) take the
 straight 10MHZ and apply this leap count technique:

 (8+8+83334+8+8+83334)*20 = one really accurately made 60HZ =
 one nice second, just the thing for a Nixie clock. :)

 Now, what is a good hex inverter to take the 10 million HZ of my rubidiom
 movement to feed a frequency divider chip (and later Arduino)? It needs to
 take the .5 of a volt sinewaIe and squarewave it and in a normal 14 pin DIP
 (breadboardable) package.


if you are not afraid of a little microcontroller programming, why not
use a software DDS approach like this:


http://www.myplace.nu/avr/minidds/index.htm

it can output a nice sine wave at 60 Hz (or whatever) from say a 10
MHz clock really easily and the frequency is also easily tunable in
software.

I built several similar low frequency (audio range) software DDS using
AVR and other microcontrollers.
I usually add a one or two stage active low pass filter after the R/2R
network. I also used to build the R/2R network out of selected 1% 10K
resistors, final resistor match is usually good to 0.1% tolerance, but
in some boards I just put 5% parts.
Software is basicly an adder and you use the highest byte as a pointer
to the ram or rom waveform samples, once you understand how it works,
it's really easy to adapt to your needs. Usually the waveform you
obtain has a DC offset, but that's easily solved too.

Hope it helps.

Frank   IZ8DWF

___
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] OT loosing things

[francesco messineo]

The answer is much simpler: the object's wave function (quantum
mechanics) can move the object, albeit with little probability :-)

Best regards

Frank

On Fri, Nov 12, 2010 at 3:18 PM, Steve Rooke sar10...@gmail.com wrote:
 I liked the idea of fairies being the culprits but each to their own :)

 I think that the LW are not completely random, they definitely return
 your own stuff to you but I don't believe it is necessarily in the
 same place.

 Ah, now a candidate for a new law. A lost item always turns up the
 moment after you have purchased it's replacement.

 Cheers,
 Steve

 On 13/11/2010, paul swed paulsw...@gmail.com wrote:
 Certainly one viable theory.
 However the answers much simpler then that and an established fact
 documented in many books by such authors as Steven King.
 Its simply ghosts at work.
 Worm wholes would not return items to the same place or area.
 Ghosts would. Although as you mention often much later, even years.
 Haven't you ever noted the stuff comes back after you buy a replacement?
 Regards

 On Fri, Nov 12, 2010 at 5:11 AM, Steve Rooke sar10...@gmail.com wrote:

 While repairing my LCD monitor, I took off my glasses so as to be able
 to see better close up as I'm VERY short sighted and even the
 vari-focals my optician prescribes can no longer get me close enough
 to solder properly. Without them on, I can focus VERY close but the
 range is VERY short, being just a few inches. So I completed the work
 involving a few stages without putting the glasses back on just to
 save time but, when I went to grope around and try to find them, I
 could not. So where did I put the blessed things, and after a period
 of serious extended looking around, blind panic started to set in.
 What the dickens had I done with them! So I ended up shuffling out of
 the workshop, through the house, stumbling over the dogs, and up to
 the bedroom to, eventually, find my spare pair. On my return to the
 workshop I still could not find the glasses looked everywhere. A cup
 of tea ensued and I took a less panicky search only to find they had
 fallen down the back of some gear, or maybe it was the fairies at the
 bottom of my garden which had done it. I concluded that in my
 blinded state of putting them down in the first place, I had
 obviously chosen an poor safe place.

 After this I got to thinking and wondered if there is perhaps
 something darker happening here. My current theory is that there is
 something called a Lost Wormhole which moves around randomly and
 removes items from there current place, setting them down in some
 completely different dimension. So the chances of loosing something
 increases in proportion to the time that the item is left somewhere
 due to the increased probability of it being borrowed by the LW.
 Now, all is not lost as the LW is a two way pipe and so eventually
 your lost item will be dropped back somewhere in your vicinity but
 probably not where you thought you had left it. To my mind, this seems
 to fit my experience of the way the World seems to work and I'm sure
 there is some law here.

 For the humour challenged, this message is :) rated.

 Please feel free to comment on my theory but perhaps this should be via
 PM.

 Thank you for your time,
 Steve

 --
 Steve Rooke - ZL3TUV  G8KVD
 The only reason for time is so that everything doesn't happen at once.
 - Einstein

 ___
 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.

 ___
 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.



 --
 Steve Rooke - ZL3TUV  G8KVD
 The only reason for time is so that everything doesn't happen at once.
 - Einstein

 ___
 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.


___
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] OT: xtal osc PN

[francesco messineo]

Hi Piotr,

many thanks for the link, I didn't know that page!
Best regards

Frank IZ8DWF

On Mon, Sep 20, 2010 at 12:05 PM, Piotr Kolodziejczyk sp3...@gmail.com wrote:
 Hi Frank,

 SM5BSZ has interesting article about measuring low PN oscillators.

 http://www.sm5bsz.com/osc/osc-design.htm

 He also describes there his NEWREF which achieved -179.5 dBc/Hz.
 You could use it as practical design example.

 Regards,
 Piotr, sp3ukk


 On Sun, Sep 19, 2010 at 10:40 PM, Mike Feher mfe...@eozinc.com wrote:

 Frank -

 DBMs are extremely cheap in the frequency range you are talking about. The
 rest, well, you just have to try. I think you are way overcomplicating
 this.
 I am still not sure why you feel you need a xtal filter. It is not going to
 help with the 100 Hz away stuff. Using simple BJTs common base
 configuration
 would give you more than enough isolation for what you are doing. Besides,
 I
 believe you will only be using one output at any given time. Sounds like
 you
 need to experiment and learn. Else just do it and see what you get. That is
 what all of us did when we needed something special, and then that way
 learned what to do and what not. As I said, nothing about your approach
 seems magical or even difficult. I have been a ham for almost 50 years.
 While in HS everything I built worked just fine. The more education I
 received the greater my expectations became, however, it did not need to
 over complicate matters. 73 - Mike

 Mike B. Feher, N4FS
 89 Arnold Blvd.
 Howell, NJ, 07731
 732-886-5960




 -Original Message-
 From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
 Behalf Of francesco messineo
 Sent: Sunday, September 19, 2010 4:12 PM
 To: Discussion of precise time and frequency measurement
 Subject: Re: [time-nuts] OT: xtal osc PN

 Hi Mike,

 On 9/19/10, Mike Feher mfe...@eozinc.com wrote:
  Frank -
 
  Great idea, so obvious I did not think of it. If you mix the 20 and 22
 you
  will only get 3 dB degradation or still very close to the -131 dBc/Hz
  relative to the 10811A. As I mentioned before the architecture is
 relevant.
  I have found that mixing does not cause any noticeable degradation, and I
  used to go all the way up to 45 GHz on military programs where it was
 very
  critical. At the frequencies you are talking about I doubt if the
 amplifiers
  will have any appreciable degradation either. Of course you have to keep
  levels in perspective, as you will not do better than kT. I also do not
  believe that dividers will have much impact. After all, a DDS is a
  divider/counter and accumulator, and PN is usually considered to be very
  close to  20logN better at the output than the reference, however, DDS
 does
  have spurious at most frequencies, but that is a discussion for another
  time. I still think your original thought is your best approach. Fast,
 easy
  and less than $100, even if you do use a used 10811A. 73 - Mike

 this approach as I said has a lot of unkown to me, for example, how to
 divide by 5 (ttl or cmos or maybe synchronous or something else?),
 then there's the doubler (diodes? jfet?), then the mixers: need them
 to be diode mixers (a classic double balanced? can be  homebrewed or
 better use ready-made?) or I can get away with something cheaper like
 fet mixer or something else?
 Finally the xtal filters, those need to be ordered, where? what
 exactly do I need as filter here in terms of poles or number of xtals?
 Not to mention I need to reuse many of the signals, this means a few
 isolation amplifiers with good isolation.
 After posing myself these questions I thought I might evaluate other
 approaches :-)

 Best regards
 Frank

 ___
 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.


 ___
 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.

 ___
 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.


___
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] Thunderbolt initial check out?

[francesco messineo]

Hello,

On Mon, Sep 20, 2010 at 12:21 PM,  d.sei...@comcast.net wrote:
 Between Tboltmon and Ladyheather, you'll see that your unit either works or 
 it doesn't. My bet is that it will work just fine, even if the antenna is 
 indoors- and then you won't be able to stop watching it (esp. with lady 
 heather) for at least a few hours... Have fun!

well, this is not entirely true. I once witnessed a tbolt that
partially worked, it wasn't able to save the position so it needed to
do a self survey at each power down and the temperature sensor
appeared also not working as it reported always the same (improbable)
temperature. It also wouldn't save any parameter different from a
factory default.
10 MHz output and pps were present. The vendor sent a replacement unit
by the way.
Just for the record anyway...

best regards

Frank

___
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] OT: xtal osc PN

[francesco messineo]

Hi

On 9/19/10, Bob Camp li...@rtty.us wrote:
 Hi

 Is -195 dbc/Hz floor good enough or is it overkill?

I'd say this is obviously overkill, -160 dBc/Hz could be a good compromise.


 Is -155 dbc/Hz at 100 Hz offset a requirement or is -40 dbc ok?

-40 dBc/Hz at 100 Hz is about useless, -150 dBc/Hz at 100 Hz is again
a good compromise, the lower (practically) the better.

It's hard to explain why to ones not familiar with weak signal
operation between broadcasting signals, but really the noise floor
raise a lot when you have some 5 or 6 broadcasts signals in 500 KHz of
band (all with power levels of at least 10 dB more than the levels
used in amateur radio, often +20 dB more)

 You need to quantify what you are after before deciding on an approach. Low
 noise means many different things to each of us.

it's a compromise, of course I can't spend years or thousand dollars
on the LO part of the setup. In the first case I'd not use it very
much (so would be useless) and in the second case I could probably pay
me a trip at the other side of the world far away from broadcasts :-)
As good as it can gets within few months and a hundred dollars (maybe
more if for useful test equipment). The rest of the parts are going to
cost less than $300 total.

Best regards

Frank  IZ8DWF

___
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] OT: xtal osc PN

[francesco messineo]

Hi Bruce,

On 9/18/10, Bruce Griffiths bruce.griffi...@xtra.co.nz wrote:
 Another reference on VHF crystal oscillator circuits (if you can read
 German) is:
 http://www.axtal.com/data/buch/Kap6.pdf
 In particular Figures 6.20 and 6.21 on page 23.


unfortunately I don't read german, but it seem I understand those
circuit are derived from a Driscoll's article that I might be able to
find.
Many thanks for the input.

Frank IZ8DWF

___
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] OT: xtal osc PN

[francesco messineo]

On 9/19/10, Magnus Danielson mag...@rubidium.dyndns.org wrote:
 Frank,

 On 09/19/2010 09:35 AM, francesco messineo wrote:
 Hi

 On 9/19/10, Bob Campli...@rtty.us  wrote:
 Hi

 Is -195 dbc/Hz floor good enough or is it overkill?

 I'd say this is obviously overkill, -160 dBc/Hz could be a good
 compromise.


 Is -155 dbc/Hz at 100 Hz offset a requirement or is -40 dbc ok?

 -40 dBc/Hz at 100 Hz is about useless, -150 dBc/Hz at 100 Hz is again
 a good compromise, the lower (practically) the better.

 Do you *really* need -150 dBc/Hz? That is a hard requirement!

 It's hard to explain why to ones not familiar with weak signal
 operation between broadcasting signals, but really the noise floor
 raise a lot when you have some 5 or 6 broadcasts signals in 500 KHz of
 band (all with power levels of at least 10 dB more than the levels
 used in amateur radio, often +20 dB more)

 I would need some more fundamental understanding of the system and needs
 to be able to understand how you come up with the above noise level at
 100 Hz.

as I said, if it's not possible or not practical, of course I'll take
what I can get. The receiver will be limited by its phase noise and
not for example by its IMD3.
I think already -110 dBc/Hz at 100 Hz is better than any LO in
commercial receivers (for ham radio at least).

Best regards
Frank

___
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] OT: xtal osc PN

[francesco messineo]

Hi Mike,

as I said, current plans are for a few frequencies in the 20-50 MHz
range. The current project needs 20, 22 and 42 MHz oscillators.

Best regards
Frank

On 9/19/10, Mike Feher mfe...@eozinc.com wrote:
 Frank -

 Did you ever mention at what center frequency you would like to achieve the
 PN at your stated offset? Regards - Mike

 Mike B. Feher, N4FS
 89 Arnold Blvd.
 Howell, NJ, 07731
 732-886-5960



 -Original Message-
 From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
 Behalf Of francesco messineo
 Sent: Sunday, September 19, 2010 12:04 PM
 To: Discussion of precise time and frequency measurement
 Subject: Re: [time-nuts] OT: xtal osc PN

 On 9/19/10, Magnus Danielson mag...@rubidium.dyndns.org wrote:
 Frank,

 On 09/19/2010 09:35 AM, francesco messineo wrote:
 Hi

 On 9/19/10, Bob Campli...@rtty.us  wrote:
 Hi

 Is -195 dbc/Hz floor good enough or is it overkill?

 I'd say this is obviously overkill, -160 dBc/Hz could be a good
 compromise.


 Is -155 dbc/Hz at 100 Hz offset a requirement or is -40 dbc ok?

 -40 dBc/Hz at 100 Hz is about useless, -150 dBc/Hz at 100 Hz is again
 a good compromise, the lower (practically) the better.

 Do you *really* need -150 dBc/Hz? That is a hard requirement!

 It's hard to explain why to ones not familiar with weak signal
 operation between broadcasting signals, but really the noise floor
 raise a lot when you have some 5 or 6 broadcasts signals in 500 KHz of
 band (all with power levels of at least 10 dB more than the levels
 used in amateur radio, often +20 dB more)

 I would need some more fundamental understanding of the system and needs
 to be able to understand how you come up with the above noise level at
 100 Hz.

 as I said, if it's not possible or not practical, of course I'll take
 what I can get. The receiver will be limited by its phase noise and
 not for example by its IMD3.
 I think already -110 dBc/Hz at 100 Hz is better than any LO in
 commercial receivers (for ham radio at least).

 Best regards
 Frank

 ___
 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.


 ___
 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.


___
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] OT: xtal osc PN

[francesco messineo]

On 9/19/10, Bob Camp li...@rtty.us wrote:
 Hi

 The key point being that a fixed oscillator will have *much* better close in
 phase noise than your typical synthesized radio.


yes, I  agree fully, in facts getting rid of the typical syntesized
radio is my final goal :-)
First step is the converter, second step will be probably an SDR at a
lower frequency.
Best regards
Frank

___
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] OT: xtal osc PN

[francesco messineo]

On 9/19/10, jimlux jim...@earthlink.net wrote:
 francesco messineo wrote:

 It's hard to explain why to ones not familiar with weak signal
 operation between broadcasting signals, but really the noise floor
 raise a lot when you have some 5 or 6 broadcasts signals in 500 KHz of
 band (all with power levels of at least 10 dB more than the levels
 used in amateur radio, often +20 dB more)
 I would need some more fundamental understanding of the system and needs
 to be able to understand how you come up with the above noise level at
 100 Hz.

 as I said, if it's not possible or not practical, of course I'll take
 what I can get. The receiver will be limited by its phase noise and
 not for example by its IMD3.
 I think already -110 dBc/Hz at 100 Hz is better than any LO in
 commercial receivers (for ham radio at least).


 But why at 100 Hz offset.  Are you looking for weak signals 100 Hz away
 from the strong interferer? (and are worried about reciprocal mixing
 from the LO)  That would imply that the interferer has equally good
 phase noise, and that's not particularly likely?

the first scenario. Even if the interferer has poor phase noise, why
folding back another share of interference on my side?
As for the 100 Hz offset, it's just a practical measure, if @100 Hz
things are good, @ 1KHz or more they must be even better, right?
In real life though, interferers are often much closer than 100 Hz to
the wanted signal and this often means no contact made (it happened
two times to me this year already).
On the other side of the contact however, the band was much more clean.


 If you want to be a good spectrum citizen and have a real clean
 transmitter...  (or you're doing some experiment where you are doing
 some sort of radio science, and need a clean, clean tx)


Clean TX is always good, but it really matters on other amateur radio
scenarios (like EME and Low Frequency among others), I don't mind
having clean TX as a side effect in my case.

Best regards
Frank

___
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] OT: xtal osc PN

[francesco messineo]

On 9/19/10, jimlux jim...@earthlink.net wrote:
 francesco messineo wrote:
 Hi Mike,

 as I said, current plans are for a few frequencies in the 20-50 MHz
 range. The current project needs 20, 22 and 42 MHz oscillators.



 But you're multiplying that up, it will be 20log(N) worse...

no, I'm using these as LO for frequency downconversion. 48, 50, 70 MHz
to 28 MHz in the first prototype.

Regards
Frank

___
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] OT: xtal osc PN

[francesco messineo]

Hi Mike,

On 9/19/10, Mike Feher mfe...@eozinc.com wrote:
 Well, if one just looks at the spec of the 10811A for relative performance,
 it is -140 dBc/Hz at 100 Hz offset at 10 MHz. Realistically, probably a
 little better. From that it would be real easy to generate the frequencies
 Frank is looking for, obviously 20 would be easy but would be only -134
 dBc/Hz at 100 Hz away. 22 would be easy by diving the 10 and mixing it with
 the 20, assuming the divide by 5 has a very small contribution, the PN of
 the resultant at 2 MHz is also theoretically 20logN better, so, mixing will
 also give close to -134 dBc at 100 Hz away. 42 can easily be generated by
 doubling the 20, to get -128 dBc at 100 Hz and then mixing with the same 2
 MHz to get the 42 MHz, still resulting in almost -128 dBc/Hz at 42 MHz.
 Obviously filters will have to be used to get rid of the unwanted lower
 mixing products. Depending on the architecture used, as stated below,
 further multiplications will again decrease these numbers by 20logN.
 Filtering at the IF with a 250 to 500 Hz filter is not going to do anything
 to the 100 Hz numbers. I assume the mode of communications here is CW, hence
 the narrow filter at IF. 73 - Mike

this exact approach (well maybe mixing 20 and 22 to obtain 42 MHz
instead of doubling 20 MHz then mixing) was my first choice but I'm
afraid I wouldn't be able to do all these steps without making any
mistake like chosing the right mixer, right filters and
multiplier/dividers.
It was really what I wanted to do, but looks like I could spend too
much time doing it and ending with a poorer result than carefully
chosen xtal oscillators.

Thanks for suggesting it though :-)

Frank IZ8DWF

___
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] OT: xtal osc PN

[francesco messineo]

Hi Mike,

On 9/19/10, Mike Feher mfe...@eozinc.com wrote:
 Frank -

 Great idea, so obvious I did not think of it. If you mix the 20 and 22 you
 will only get 3 dB degradation or still very close to the -131 dBc/Hz
 relative to the 10811A. As I mentioned before the architecture is relevant.
 I have found that mixing does not cause any noticeable degradation, and I
 used to go all the way up to 45 GHz on military programs where it was very
 critical. At the frequencies you are talking about I doubt if the amplifiers
 will have any appreciable degradation either. Of course you have to keep
 levels in perspective, as you will not do better than kT. I also do not
 believe that dividers will have much impact. After all, a DDS is a
 divider/counter and accumulator, and PN is usually considered to be very
 close to  20logN better at the output than the reference, however, DDS does
 have spurious at most frequencies, but that is a discussion for another
 time. I still think your original thought is your best approach. Fast, easy
 and less than $100, even if you do use a used 10811A. 73 - Mike

this approach as I said has a lot of unkown to me, for example, how to
divide by 5 (ttl or cmos or maybe synchronous or something else?),
then there's the doubler (diodes? jfet?), then the mixers: need them
to be diode mixers (a classic double balanced? can be  homebrewed or
better use ready-made?) or I can get away with something cheaper like
fet mixer or something else?
Finally the xtal filters, those need to be ordered, where? what
exactly do I need as filter here in terms of poles or number of xtals?
Not to mention I need to reuse many of the signals, this means a few
isolation amplifiers with good isolation.
After posing myself these questions I thought I might evaluate other
approaches :-)

Best regards
Frank

___
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.

[time-nuts] OT: xtal osc PN

[francesco messineo]

Hello all,

sorry for the OT, but the electronic expertise of the group is too good :-)

I'm looking for ideas and directions (articles and so on) to realize
very good phase noise xtal oscillator, in the range 20-50 MHz for high
performance frequency conversion. I would like to understand what
circuits can be realized (not requiring too much professional and
modern equipment, test eq. from the 70s-80s is ok) and what is the
contribution of the active oscillator device, the xtal itself and the
following buffers.
Another idea that came on my mind was using digital oscillator (square
wave, cmos) and then filtering for sine output, if this makes sense
for a low PN point of view.
Is there any way to measure the close-in PN of oscillators with an
amateur setup?

Thanks in advance

Frank IZ8DWF

___
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] OT: xtal osc PN

[francesco messineo]

First of all, thanks to John and Magnus for inputs and links, makes a
very good start!

On 9/18/10, Magnus Danielson mag...@rubidium.dyndns.org wrote:
 On 09/18/2010 09:48 AM, francesco messineo wrote:
 Hello all,

 sorry for the OT, but the electronic expertise of the group is too good
 :-)

 I'm looking for ideas and directions (articles and so on) to realize
 very good phase noise xtal oscillator, in the range 20-50 MHz for high
 performance frequency conversion. I would like to understand what
 circuits can be realized (not requiring too much professional and
 modern equipment, test eq. from the 70s-80s is ok) and what is the
 contribution of the active oscillator device, the xtal itself and the
 following buffers.
 Another idea that came on my mind was using digital oscillator (square
 wave, cmos) and then filtering for sine output, if this makes sense
 for a low PN point of view.
 Is there any way to measure the close-in PN of oscillators with an
 amateur setup?

 First of all I think you need to quantify what you mean by high
 performance frequency conversion and what stability measures you are
 seeking as there are many degrees of excessiveness to attempt, and many
 of them may be well beyond what you need. Remember, we are time-nuts... :)


Ok, let's say as good as practically and economically feasible for
single prototype and homebuilder. I already chosed not to use a
Si570 because I really need only few (2-4) fixed frequencies and I'm
assuming that carefully made xtal oscillators can beat the Si570 phase
noise performance.
The conversion is obviously for a receiver, not for  the classic HF
bands, but  for the lower VHF amateur bands (50-70 MHz) where IMD3
performance of the receiver has to be the best possible, as these
bands are used for TV and radio broadcasts in many nearby countries
around here.
Of course a very good frontend BPF, amplifier and mixer are needed,
but these are less of a problem for me to chose (and are simpler to
evaluate with standard test equipment too).
Unfortunately I know very few  low-VHF-nuts and very few of them (if
any) realize their setup performance are so far distant from what can
be achieved nowadays.

Thanks again

Frank  IZ8DWF

___
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] OT: xtal osc PN

[francesco messineo]

On 9/18/10, Magnus Danielson mag...@rubidium.dyndns.org wrote:
 On 09/18/2010 02:41 PM, francesco messineo wrote:
 First of all, thanks to John and Magnus for inputs and links, makes a
 very good start!

 On 9/18/10, Magnus Danielsonmag...@rubidium.dyndns.org  wrote:
 On 09/18/2010 09:48 AM, francesco messineo wrote:
 Hello all,

 sorry for the OT, but the electronic expertise of the group is too good
 :-)

 I'm looking for ideas and directions (articles and so on) to realize
 very good phase noise xtal oscillator, in the range 20-50 MHz for high
 performance frequency conversion. I would like to understand what
 circuits can be realized (not requiring too much professional and
 modern equipment, test eq. from the 70s-80s is ok) and what is the
 contribution of the active oscillator device, the xtal itself and the
 following buffers.
 Another idea that came on my mind was using digital oscillator (square
 wave, cmos) and then filtering for sine output, if this makes sense
 for a low PN point of view.
 Is there any way to measure the close-in PN of oscillators with an
 amateur setup?

 First of all I think you need to quantify what you mean by high
 performance frequency conversion and what stability measures you are
 seeking as there are many degrees of excessiveness to attempt, and many
 of them may be well beyond what you need. Remember, we are time-nuts...
 :)


 Ok, let's say as good as practically and economically feasible for
 single prototype and homebuilder. I already chosed not to use a
 Si570 because I really need only few (2-4) fixed frequencies and I'm
 assuming that carefully made xtal oscillators can beat the Si570 phase
 noise performance.
 The conversion is obviously for a receiver, not for  the classic HF
 bands, but  for the lower VHF amateur bands (50-70 MHz) where IMD3
 performance of the receiver has to be the best possible, as these
 bands are used for TV and radio broadcasts in many nearby countries
 around here.
 Of course a very good frontend BPF, amplifier and mixer are needed,
 but these are less of a problem for me to chose (and are simpler to
 evaluate with standard test equipment too).
 Unfortunately I know very few  low-VHF-nuts and very few of them (if
 any) realize their setup performance are so far distant from what can
 be achieved nowadays.

 One solution would use a stable standard oscillator, say 10 MHz, and
 then use a bandpass filter to select suitable overtones for first
 mixdown. You can select several options for selection of overtones, but
 fixed LC-resonators comes to mind.

This is a neat idea, but works only for overtones of the standard,
some of my needed frequencies aren't overtone of 10 (or 5) MHz.


 Another variant is to use a fairly low-noise VCO and then PLL lock it
 with wide bandwidth to a stable fixed reference (such as a 5 or 10 MHz
 TCXO or OCXO of your choice, possibly divided down to suitable
 step-frequency) as the PLL does some interesting things with phase
 noise... within the PLL bandwidth the reference phase noise will
 dominate where as outside of the PLL bandwidth the VCO phase noise will
 dominate. This comes in handy, and for such PLL applications you want
 the PLL to be wideband.

this is also interesting, but again, isn't a PLL overkill for just 4
fixed frequencies? I don't mind building separate oscillators. However
the PLL approach could be interesting for other reasons (stability),
any pointer? :-)



 A third alternative is to again let a stable reference of choice drive a
 modern DDS chip, for instance AD9971 or so.

 I am not a radio amateur, so I won't be able to say which is the best
 solution for your needs, but that is at least what I would be looking at
 if I where to build something like this.


the best solution depends on many factors:

-) if there were many others with my same needs, we'd probably find
better to use a modern DDS (share the pcb making and someone who can
do the soldering of such packages), instead, so far the low-VHF people
aren't generally aware that better frontends are possible, you find
lot of work in the HF receivers and next to nothing in the lower VHF
where big signals and intermodulations come from broadcasts and not
from other amateur stations!

-) if much more than 4 different frequencies would be needed, then PLL
would be the best choice anyway;

-) if cost was not an issue, probably the best thing would be ordering
4 ready made OCXO from a respectable company :-)



 The link to Enrico I sent you is more the knowledge of the field, but if
 you follow the links to Wenzel and Bruce stuff you have some designs to
 look at. I wonder if you really need to go deep into the field to get
 satisfied.

Probably not that deep, I'm convinced that a well studied and known
good xtal oscillator circuit could already do the job, I'm just not
able to judge the circuit myself, so I must ask for other's advice
(while I try to setup my own PN test bed).

Best regards

Frank  IZ8DWF

Re: [time-nuts] OT: xtal osc PN

[francesco messineo]

On 9/18/10, Magnus Danielson mag...@rubidium.dyndns.org wrote:


 A simple PLL is not that complex these days. As long as you have fairly
 high comparator frequency after dividing down the VCO and reference you
 could get away fairly easilly. Standard programmable dividers in the TTL
 family and a single chip for phase-comparator will work fairly well.
 There is gazillions of examples among hams for this approach.

sure, but I'd need to at least understand what's low noise and what's
not again :-)



 -) if there were many others with my same needs, we'd probably find
 better to use a modern DDS (share the pcb making and someone who can
 do the soldering of such packages), instead, so far the low-VHF people
 aren't generally aware that better frontends are possible, you find
 lot of work in the HF receivers and next to nothing in the lower VHF
 where big signals and intermodulations come from broadcasts and not
 from other amateur stations!

 Maybe the DDS board from the DMTD project would fit your needs?

maybe, I didn't follow that thread, what DDS chip is used? What's the
clock source?
In this moment I'd pretty much like it fits my needs, also because of
Rick's comment (I would order custom made xtals if it's not going to
cost more than the rest of the parts and if I know what to order).


Regards
Frank  IZ8DWF

___
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] nubie querie

[francesco messineo]

On 3/10/10, David Forbes dfor...@dakotacom.net wrote:

  With regard to the restoration and use of a derelict radio telescope for
 amateur radio, that's a fine example of amateurs putting themselves to a big
 task and succeeding. I work on radio telescopes, so I know how big a task
 that is.


Here in Italy, radio telescopes, brand new ones like the Sardinia
Radio Telescope, get abandoned just a minute after they've been built
(or a minute before maybe).
I whish radio amateurs could have any role in rescuing such a great
tool for research and science (64m dish). Government looks not so
interested in science here.

Frank  IZ8DWF (IS0FKQ some years ago)

___
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.

[time-nuts] thunderbolt fault

[francesco messineo]

Hi all,

A friend just received a thunderbolt from an ebay seller today and
asked me to check it and wire a quick power supply for him.
I used a switching power supply, pc-like, just for testing and tried
both lady heather and tboltmon. I wired the power lines as the TVB web
page, but connected only one GND line as the connector supplied didn't
have enough wires. The unit completes the self-survey and has all
outputs (10 MHz and PPS), however, the temperature starts at -0 C at
power on and in a few seconds settles to -1.249 C and never moves
again. Also eeprom contents is invalid at each power on and no setting
appears to survive after power off (not even the saved position).
Does anyone know if there's a simple explanation for this or a
possible common fault for eeprom and temperature or both eeprom and
termometer chip are probably bad?
I suggested the friend to ask for a refund anyway as my own
thunderbolt works fine with default settings.

Regards
Francesco IZ8DWF

___
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] thunderbolt fault

[francesco messineo]

Hi Stan,

On 2/26/10, Stan, W1LE stanw...@verizon.net wrote:
 Hello Francesco,

  After connecting to a known good power supply, active antenna, and
 computer,
  give it a chance to warm up and stabilize.

  After warm up, I get:
  +5VDC @ 0.250 A
  +12VDC @ 0.12 A
  -9VDC @ very low current, just barely moving the meter...


it's actually +5V,+12 and -12V.
Are there different versions? Mine works fine with these voltages,
seen the requirement on the manual.
However it completed the self survey two times and I set the save
position flag. As I said I have one unit working fine, so I know what
to expect from it. Each time the power goes off, it is reset to all
defaults and eeprom is reported corrupted.
I'll try an hard reset however.

Thanks
Francesco IZ8DWF

___
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.

[time-nuts] OT: Practical PLL low noise?

[francesco messineo]

Hello all,
sorry for the OT, but I know there're many real electronic artists here.

As an amateur radio operator I often use transverters, some home made.
They usually can be made sigthly better (RF and noise-wise) than
japanese transceivers. However often the LO xtal oscillator drifts too
much for comfortable digital and weak signal work.
Now the big question: is there any PLL design that can lock 22 MHz and
42 MHz xtal oscillator to a 10 MHz reference (typically from a GPSDO)
without adding significant noise to the oscillators? The LOs usually
go to a single or doube balanced diode mixer like the famous
minicircuit ones, and at that point the RF signal has been already
amplified by 10 or 20 dB stage(s).
Other options would be ovenizing the LOs or making a DDS sinth.
Now, what would be more practical approach from the home construction point?
Thanks
Frank IZ8DWF

___
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] OT: Practical PLL low noise?

[francesco messineo]

Hi Bob,

On 2/2/10, Bob Camp li...@cq.nu wrote:
 Hi

  The first issue - your oscillator may be drifting quite a lot. If so, that's
  the first thing to check and possibly fix. A reasonable oscillator should be
  able to hold less than 100 Hz at 42 MHz under normal room conditions. Fixes
  range from circuit improvements, to a better crystal, to simply eliminating
  a draft that blows on the oscillator.

it is drifting about 50 Hz during warm up, but the problem is thermal
drift internally as season changes, as tx/rx periods change, and so
on.

  If the oscillator is reasonably stable, it will need to be turned into a
  VCXO in order to lock it. If both oscillators use fundamental crystals, that
  should not be very hard. If they use higher overtone crystals it may be more
  of a challenge. Often you will find a tradeoff between good oscillator
  performance and wide tuning range.

22 MHz can be fundamental, 42 MHz is third overtone for sure.


  What ever chip you use to do the lock, keep the loop bandwidth small. The
  GPSDO will be noisy and it will not help you for phase noise. I would start
  the bandwidth at 100 Hz to be sure everything works ok and then start
  narrowing it to 10 Hz or less. At some point the loop will be to narrow to
  keep up with the changes and you will not be able to maintain phase lock.

  What ever loop bandwidth you use, keep the phase margin large. You do not
  need a fast locking loop. Instead you need one that has less tendency to
  peak. Phase margins should be above 70 degrees.

  The nice thing about doing this with a chip is that most of the
  manufacturers have cute little web applications / free downloads to design
  the loop filters for you. No digging out crazy formulas and wondering if you
  got it all right.


thanks for the suggestions, any good candidate as a chip?

73
Frank IZ8DWF

___
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] Low noise PLL for transceiver locking

[francesco messineo]

Hi Murray,

On 2/2/10, Murray Greenman murray.green...@rakon.com wrote:
 Frank,

  My suggestion would be to try injection locking, rather than a PLL. No
  change is made to the 22MHz and 42MHz oscillators, except to find a way
  to inject enough reference power to force them to lock to it. Injection
  locking works well with modest harmonic relationships, and gives good
  noise performance. The injection can be via a coupling link, or even at
  the cold end of an existing bypass capacitor. Narrow pulses often work
  best.

  I am confident that you could lock 22MHz to a 2MHz injection (divided
  from your 10MHz reference) if the 2MHz pulse was narrow enough and the
  22MHz oscillator sufficiently stable. 42MHz is more of a challenge - you
  might need a double-step, such as first locking 7MHz to 1MHz from the
  reference, and using that to lock 42MHz.

I confess I've never heard about injection locking! Do you have any
suggestion where
to start from to learn about it?

73
Frank IZ8DWF

___
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] Low noise PLL for transceiver locking

[francesco messineo]

Hi Murray,

On 2/2/10, Murray Greenman murray.green...@rakon.com wrote:
 Frank,

  My suggestion would be to try injection locking, rather than a PLL. No
  change is made to the 22MHz and 42MHz oscillators, except to find a way
  to inject enough reference power to force them to lock to it. Injection
  locking works well with modest harmonic relationships, and gives good
  noise performance. The injection can be via a coupling link, or even at
  the cold end of an existing bypass capacitor. Narrow pulses often work
  best.

  I am confident that you could lock 22MHz to a 2MHz injection (divided
  from your 10MHz reference) if the 2MHz pulse was narrow enough and the
  22MHz oscillator sufficiently stable. 42MHz is more of a challenge - you
  might need a double-step, such as first locking 7MHz to 1MHz from the
  reference, and using that to lock 42MHz.

I confess I've never heard about injection locking! Do you have any
suggestion where
to start from to learn about it?

73
Frank IZ8DWF

___
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] FW: Injection locking

[francesco messineo]

Hi Murray and all,

Yes, indeed injection locking looks very interesting, and I started
reading around. Seems relatively easy for 22 MHz, but not as easy for
42 MHz (good values should be 6 or 7 MHz, right?).
So far the practical circuit I've seen are few, and this would make me
lean in favour of
direct synthesys which indeed looks easy but forces me to abandon the
old oscillator
circuits.
In the next days I'll try simulating a few ideas with spice and then decide.

First wild idea: how about making two CMOS gate xtal oscillators with
injection locking as you describe? I'd need 2 MHz (10 divided by five)
for the 22 MHz, but how practical would be obtaining the 6 or 7 MHz
from 10 MHz? It would need another oscillator locked

Thanks

Frank IZ8DWF

On 2/2/10, Murray Greenman murray.green...@rakon.com wrote:


  -Original Message-
  From: Murray Greenman
  Sent: Wednesday, 3 February 2010 9:00 a.m.
  To: 'time-nuts@febo.com'
  Subject: Injection locking

  Frank,

  Bruce's collection would be a good place to start. Thanks Bruce. Most of
  the examples relate to microwave applications, where often there is no
  alternative, but the approach works well on HF and VHF as well, and more
  importantly, can be achieved with existing oscillators with little
  modification. The IL technique works with ratios from 20:1 to 1:20 or
  more, and works well with the GPSDO as a reference.

  My experience is mostly with locking HF crystal oscillators. It works
  with overtone as well as fundamental oscillators. With an overtone
  oscillator you can couple into the mode suppression choke. With a tuned
  tank Pierce oscillator you can couple into the output tank. With a
  Colpitts, inject into the emitter, collector, or bottom of the crystal.
  I have made an excellent 10MHz CMOS gate oscillator with 2MHz injection
  into a varicap acting as one of the crystal load caps (output side).

  Kit VK2LL and others have used 10MHz injection to lock the 20MHz
  reference in common Icom HF transceivers.

  Arguably the father of the Injection Locking technique would be Vasil
  Uzunoglu, and I have some references for articles by him. The most
  readable article is Synchronous Oscillator outperforms the PLL (from
  EDN 1999) http://www.edn.com/contents/images/46326.pdf. It shows how to
  emitter-lock a conventional Colpitts oscillator. The secret here is to
  get the bias correct. The test and measurement techniques he uses are a
  good way to assess performance. Robert Adler (inventor of the TV
  remote!) also explored the IL technique.

  See:

  http://www.edn.com/contents/images/46326.pdf
  US Patent 4,355,404 Carrier Recovery Network for QPSK Modems employing
  Synchronized Oscillators, Uzunoglu 1982
  US Patent 6,580,330 Injection Locked Oscillator Automatic Frequency
  Centering method and Apparatus, Katznelson  Petrovic 2003 (has a good
  list of background papers to read)
  A study of locking oscillators... Proc IEEE R Adler 1973
  http://ieeexplore.ieee.org/iel5/5/31361/31173/01451222.pdf
  http://en.wikipedia.org/wiki/Injection_locking
  http://www.amalgamate2000.com/radio-hobbies/radio/synchronous_oscillator
  .htm
  http://potol.eecs.berkeley.edu/~jr/research/PDFs/2009-01-ASPDAC-Bhansali
  -Roychowdhury-GenAdler.pdf
  http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.130.2535rep=re
  p1type=pdf

  That should keep you busy for a while!

  73,
  Murray ZL1BPU



  ___
  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.


___
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] FW: Injection locking

[francesco messineo]

On 2/2/10, Bruce Griffiths bruce.griffi...@xtra.co.nz wrote:
 However injection locking also works when the frequencies ratios involved
 are rational numbers.
  For 22MHz and 10MHz, the corresponding ratio is 11/5 a rational number.
  For 42MHz and 10MHz, the frequency ratio is 21/5 a rational number

Then 2 MHz would work for both, obtaining 2 MHz from 10 MHz is quite
easy, HP AN-301-1
plus a 74LS193 would do it.
If I can make it work with the current oscillator design I'm using, I
can easily adapt it also to already made transverters, very tempting.

Frank

___
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] HP 105B Modification

[francesco messineo]

Hi all,

indeed this is very interesting, can this buffer amplifier be used as
a building block for a distribution amplifier for the 10 MHz signal of
a thunderbolt? I remember having seen on the list a similar version
but with european transistors (like the ubiquitous bc548/bc558?) that
are very common here, but I can't remember when it was to surf the
list archives in the right time-period. Anyone?
best regards

Francesco IZ8DWF

On 12/9/09, Ed Palmer ed_pal...@sasktel.net wrote:
 I was thinking that I might be reinventing the wheel by designing a buffer
 amp.  You guys have almost built the entire car!  Thanks again for the
 ideas.  It'll take me a while to get it built and tested.

  Ed

  Bruce Griffiths wrote:

  John Miles wrote:
 
  
  
   
 If it helps I can send you some LTSpice schematics so that you can
 simulate the circuit for yourself.
 The breadboards behave as predicted by the simulations at 10MHz.

 John Miles has done some preliminary phase noise measurements on his
 version.

 The transformers are wound on binocular ferrite cores.
 I used some 14mm (long) cores intended for 40MHz to 220MHz (I had
 some)
 operation in my breadboard which works well at 5MHz and 10Mhz.


You can also use an off-the-shelf Mini-Circuits transformer for
 low-power
applications.  The T13-1 was the one I tried.  I'll stick some of
the plots
up on the web later tonight if possible.
   
   
   See http://www.ke5fx.com/norton.htm for measurements
 and connection details
   of the copy of Bruce's amp that I added to my 5061A.
  
   -- john, KE5FX
  
  
  
  Note the LED I used in the schematic was merely for simulation purposes
 (ie LTSpice had a model for it).
  A standard red or amber LED is just fine.
 
  Another point is the LTSpice LED model isn't particularly accurate for
 simulating the effects of temperature variations.
  Does anyone knows of more accurate LTSpice compatible LED models?
 
  The LED model voltage drop increases with temperature even at low current,
 whilst the voltage drop across a real LED at low currents decreases with
 temperature.
  In practice the variation in the LED forward drop tracks the variation in
 the pnp Vbe quite well.
 
  Bruce
 
 

  ___
  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.


___
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] HP 105B Modification

[francesco messineo]

Hello Bruce,

On 12/9/09, Bruce Griffiths bruce.griffi...@xtra.co.nz wrote:
 Francesco

  Yes, just keep the gain of each stage low and cascade 2 or3 if you need
 higher reverse isolation.
  Since the input impedance is around 1k (predominantly capacitive) at 10MHz
 you can drive several in parallel from a 50 ohm source.
  If needed you can add a bridged T-coil network at the input to improve the
 broad band matching.


I would have one stage from the thunderbolt and then two cascaded
stages for each output all from the single first stage, would that
work? I'm not sure that for ordinary frequency distribution I need a
better level of isolation. I may be wrong of course.

  If you need 100MHz operation just substitute a 4GHz ft transistor for the
 2N5109/2N5943.

only 10 MHz!

  In this case you may need to reduce the supply volatage dependent on the
 transistor ratings.

  I've simulated cascades of 3 such amplifiers and found that the phase noise
 remains low.
  The only thing to watch when cascading for improved isolation is reverse
 coupling via the common power supply.
  However with well planned supply decoupling this won't be a problem.

ok, I got the hint :-)


  The ft of the BC548/558 is only 300MHz compared to ~ 1GHz or so for the
 2N5109/2N5943, so reverse isolation at high frequencies will be worse when
 you use the BC548/558.

as I said I just need this to work at precisely 10 MHz, and the
BC548/558 are a free (really) item here!
But maybe there could be a problem if one equipment puts back higher
frequency noise on its 10 MHz input? This could be solved by filtering
at each output?
Maybe one day I will use a similar stage to bring the IF signal out of
some of my amateur radio transceiver, but that's not something I plan
to do soon (I don't see the need for it currently) and in that case I
will use better transistors for sure.
Thanks
Francesco


  Bruce

  francesco messineo wrote:

  Hi all,
 
  indeed this is very interesting, can this buffer amplifier be used as
  a building block for a distribution amplifier for the 10 MHz signal of
  a thunderbolt? I remember having seen on the list a similar version
  but with european transistors (like the ubiquitous bc548/bc558?) that
  are very common here, but I can't remember when it was to surf the
  list archives in the right time-period. Anyone?
  best regards
 
  Francesco IZ8DWF
 
  On 12/9/09, Ed Palmered_pal...@sasktel.net  wrote:
 
 
   I was thinking that I might be reinventing the wheel by designing a
 buffer
   amp.  You guys have almost built the entire car!  Thanks again for the
   ideas.  It'll take me a while to get it built and tested.
  
Ed
  
Bruce Griffiths wrote:
  
  
  
John Miles wrote:
   
   
   



 
 
   If it helps I can send you some LTSpice schematics so that you
 can
   simulate the circuit for yourself.
   The breadboards behave as predicted by the simulations at 10MHz.
  
   John Miles has done some preliminary phase noise measurements on
 his
   version.
  
   The transformers are wound on binocular ferrite cores.
   I used some 14mm (long) cores intended for 40MHz to 220MHz (I
 had
  
  
 

   
   some)
  
  
   

 
   operation in my breadboard which works well at 5MHz and 10Mhz.
  
  
  
  
  You can also use an off-the-shelf Mini-Circuits transformer for
 
 

   
   low-power
  
  
   

  applications.  The T13-1 was the one I tried.  I'll stick some of
  the plots
  up on the web later tonight if possible.
 
 
 
 
 See http://www.ke5fx.com/norton.htm for
 measurements


   
   and connection details
  
  
   
 of the copy of Bruce's amp that I added to my 5061A.

 -- john, KE5FX





Note the LED I used in the schematic was merely for simulation
 purposes
   
   
   (ie LTSpice had a model for it).
  
  
A standard red or amber LED is just fine.
   
Another point is the LTSpice LED model isn't particularly accurate for
   
   
   simulating the effects of temperature variations.
  
  
Does anyone knows of more accurate LTSpice compatible LED models?
   
The LED model voltage drop increases with temperature even at low
 current,
   
   
   whilst the voltage drop across a real LED at low currents decreases with
   temperature.
  
  
In practice the variation in the LED forward drop tracks the variation
 in
   
   
   the pnp Vbe quite well.
  
  
Bruce
   
   
   
   
___
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.
  
  
  
  ___
  time-nuts mailing list -- time-nuts@febo.com
  To unsubscribe, go to
 https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts

Re: [time-nuts] Amatuer Radio Information

[francesco messineo]

On 11/25/09, Robert Darlington rdarling...@gmail.com wrote:

  Out here I'm almost exclusively on HF bands using the modern digital
  communications modes like PSK31.  The first license (Technician) will not
  get you on the HF bands unless you count 6 meter (50MHz) as HF.

well, 6m isn't anything like HF (imho).

  In 10 years
  I haven't heard a soul on 6 so I don't really even bother with listening
  anymore.  To get on HF, the General license will get you 95% of what Extra

wow... I think I worked something like 90 dxcc countries with modest
setup in less than three years (but that was in 2001-2003).
For sure I worked all europe and all african active countries with 10W
into a homemade vertical J-pole antenna back in the best years of the
last solar cycle.
Now with a medium-sized beam in the right months I can work from USA
to Japan (with 100W only).
I see from the cluster spots that USA and all american continent are
also much more blessed with 6m propagation all the year with respect
to europe in this very low cycle minimum.
Sorry for the extreme off-topic, but it's just to witness that VHF
isn't dead and many of us don't even have HF antennas and still enjoy
the activity in the VHF challenging bands all the year.
Amateur radio has so many different aspect that any technical person
can find always new challenging aspects to explore.
No band is dead if someone has the right interest in it!

best 73
F

___
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] Lady Heather question serial error

[francesco messineo]

On 2/21/09, Magnus Danielson mag...@rubidium.dyndns.org wrote:

  I'm considering a Linux port since I want to reduce my dependency on
  Windows at all times.


before knowing about the existence of lady heather I had started
coding a very simple Linux/Unix program that would work much like
tboltmon.exe (ncurses based). Then I tried both Dos (under dosemu) and
windows (under wine) versions of lady heather and they work just fine,
so I abandoned (for now) that effort.
I don't have any dependance on windows, I actually don't have any
windows box around.

Regards

Frank IZ8DWF

___
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] rockwell gps chipset datasheet?

[francesco messineo]

Hi Roberto,

On 2/17/09, Roberto Barrios rbarri...@msn.com wrote:
 Hi Frank,

  The Rockwell 11577-11 is found in most TU-DXXX Rockwell-Jupiter GPS
  receivers. I've never seen anything like a RF switch on them, but you could
  have a custom or exotic one :). What they do have most times is a model
  number etched or printed on the PCB. Doesn't yours have one?


the PCB is custom made from an italian company, I could try to ask
them if they still exists, but it's very difficult that they release
any info about it anyway.
The RF switch is there to software select one of two antennas,
probably for redundancy, given the particular application for which it
has been made.

  You can find a few Rockwell GPS datasheets here, where you can compare yours
  with the pictures: http://www.gpskit.nl/downloads-nl.htm

I already seen this site, but there's no component level datasheet, on
my board only the two rockwell chips have been used, and probably in a
custom design.

Best regards

Frank IZ8DWF

___
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] Rockwell GPS Chipset

[francesco messineo]

On 2/17/09, Tom Clifton kc0...@yahoo.com wrote:
 Any chance it is a Jupiter?

  http://www.gpskit.nl/gps-readme.html

  If so, they are fine receivers. THe header pins are 2mm spcing - same as 
 used on laptop hard drive adaptors


It uses the same two chips (at least in one photo of a jupiter I have
seen the 11577-11, but the board I have is custom made with these
chips. To identify the right signals I'd have to find the pinout of
the rockwell chips.

Thanks
Frank IZ8DWF

___
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.