Re: [time-nuts] PCB for frequency dividers

[David C. Partridge]

So if Au isn't the thing, what's the better answer?   HASL Sn is the other
common option and I can smell tin whiskers as the counter argument to that.
Electroless Ag?

Don't even think of suggesting regular HASL Sn/Pb - none of the PCB shops
will do that here (RoHS).

Dave 

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Bruce Griffiths
Sent: 24 July 2008 22:51
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] PCB for frequency dividers

Au plating leaves the solder joints vulnerable to the formation of the AuSn
intermetallic compound which will lead to joint failure.
You may need to remove the Au before soldering.


___
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] PCB for frequency dividers

[John Day]

Oops! Left out the link: http://www.myropcb.com


At 09:14 PM 7/24/2008, you wrote:
>At 06:34 PM 7/24/2008, you wrote:
>
>Yikes, those are both expensive. http://myropcb.com/
>
>Online quote system is very accurate. I have used them for 12x13inch
>6 layer, very reasonable and plenty of smaller 2 and 4 layer PCB's.
>They are reliable, speedy and accurate.
>
>John
>
>Try these people: S1D13513
>
> >Check out MYLYDIA.COM  ... for around $720 ($320 setup plus $0.20 /
> >sq in x 2000 sq in minimum) you can get 115 circuit boards with
> >solder mask and silk screen ($6.30 per board if you can sell them
> >all).   Even if you sell a dozen of them,  it's cheaper than what
> >you are considering...
> >
> >
> >_
> >Keep your kids safer online with Windows Live Family Safety.
> >http://www.windowslive.com/family_safety/overview.html?ocid=TXT_TAG 
> LM_WL_family_safety_072008
> >___
> >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.
> >
> >
> >--
> >No virus found in this incoming message.
> >Checked by AVG.
> >Version: 7.5.524 / Virus Database: 270.5.5/1571 - Release Date:
> >7/24/2008 5:42 PM
>
>
>___
>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.
>
>
>--
>No virus found in this incoming message.
>Checked by AVG.
>Version: 7.5.524 / Virus Database: 270.5.5/1571 - Release Date: 
>7/24/2008 5:42 PM


___
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] PCB for frequency dividers

[John Day]

At 06:34 PM 7/24/2008, you wrote:

Yikes, those are both expensive. http://myropcb.com/

Online quote system is very accurate. I have used them for 12x13inch 
6 layer, very reasonable and plenty of smaller 2 and 4 layer PCB's. 
They are reliable, speedy and accurate.

John

Try these people: S1D13513

>Check out MYLYDIA.COM  ... for around $720 ($320 setup plus $0.20 / 
>sq in x 2000 sq in minimum) you can get 115 circuit boards with 
>solder mask and silk screen ($6.30 per board if you can sell them 
>all).   Even if you sell a dozen of them,  it's cheaper than what 
>you are considering...
>
>
>_
>Keep your kids safer online with Windows Live Family Safety.
>http://www.windowslive.com/family_safety/overview.html?ocid=TXT_TAGLM_WL_family_safety_072008
>___
>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.
>
>
>--
>No virus found in this incoming message.
>Checked by AVG.
>Version: 7.5.524 / Virus Database: 270.5.5/1571 - Release Date: 
>7/24/2008 5:42 PM


___
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] PCB for frequency dividers

[Mark Sims]

Check out MYLYDIA.COM  ... for around $720 ($320 setup plus $0.20 / sq in x 
2000 sq in minimum) you can get 115 circuit boards with solder mask and silk 
screen ($6.30 per board if you can sell them all).   Even if you sell a dozen 
of them,  it's cheaper than what you are considering...


_
Keep your kids safer online with Windows Live Family Safety.
http://www.windowslive.com/family_safety/overview.html?ocid=TXT_TAGLM_WL_family_safety_072008
___
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] [Fwd: Re: PCB for frequency dividers]

[Bruce Griffiths]

Additional link on soldering of Au plated Ni surfaces:

http://www.tkb-4u.com/articles/soldering/sgons/sgons.php

Includes some info on problems in soldering Nickel.

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] [Fwd: Re: PCB for frequency dividers]

[Bruce Griffiths]

--- Begin Message ---

Daun Yeagley wrote:
I get the following error: 
File not available. [S1431927605504483a.pdf].


Daun 


-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Bruce Griffiths
Sent: Thursday, July 24, 2008 5:56 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] PCB for frequency dividers

For some some images illustrating the intermetallic problem at the
microscopic level see:
http://journals.cambridge.org/download.php?file=%2FMAM%2FMAM11_S02%2FS143192
7605504483a.pdf&code=bdfd9822c124e17308c095f29250a990



Bruce


  

Try this link:

http://journals.cambridge.org/production/action/cjoGetFulltext?fulltextid=326392

Bruce

--- End Message ---
___
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] PCB for frequency dividers

[Bruce Griffiths]

Daun Yeagley wrote:
> I get the following error: 
> File not available. [S1431927605504483a.pdf].
>
> Daun 
>
> -Original Message-
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
> Behalf Of Bruce Griffiths
> Sent: Thursday, July 24, 2008 5:56 PM
> To: Discussion of precise time and frequency measurement
> Subject: Re: [time-nuts] PCB for frequency dividers
>
> For some some images illustrating the intermetallic problem at the
> microscopic level see:
> http://journals.cambridge.org/download.php?file=%2FMAM%2FMAM11_S02%2FS143192
> 7605504483a.pdf&code=bdfd9822c124e17308c095f29250a990
>  27605504483a.pdf&code=bdfd9822c124e17308c095f29250a990>
>
>
> Bruce
>
>
>   
Try this link:

http://journals.cambridge.org/production/action/cjoGetFulltext?fulltextid=326392

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.

Re: [time-nuts] PCB for frequency dividers

[Had]

Yup, same error I got.

Had, K7MLR


At 03:01 PM 7/24/2008, you wrote:
>I get the following error:
>File not available. [S1431927605504483a.pdf].
>
>Daun
>
>-Original Message-
>From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
>Behalf Of Bruce Griffiths
>Sent: Thursday, July 24, 2008 5:56 PM
>To: Discussion of precise time and frequency measurement
>Subject: Re: [time-nuts] PCB for frequency dividers
>
>For some some images illustrating the intermetallic problem at the
>microscopic level see:
>http://journals.cambridge.org/download.php?file=%2FMAM%2FMAM11_S02%2FS143192
>7605504483a.pdf&code=bdfd9822c124e17308c095f29250a990
>27605504483a.pdf&code=bdfd9822c124e17308c095f29250a990>
>
>
>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.
___
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] PCB for frequency dividers

[Daun Yeagley]

I get the following error: 
File not available. [S1431927605504483a.pdf].

Daun 

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Bruce Griffiths
Sent: Thursday, July 24, 2008 5:56 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] PCB for frequency dividers

For some some images illustrating the intermetallic problem at the
microscopic level see:
http://journals.cambridge.org/download.php?file=%2FMAM%2FMAM11_S02%2FS143192
7605504483a.pdf&code=bdfd9822c124e17308c095f29250a990



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] PCB for frequency dividers

[Bruce Griffiths]

For some some images illustrating the intermetallic problem at the 
microscopic level see:
http://journals.cambridge.org/download.php?file=%2FMAM%2FMAM11_S02%2FS1431927605504483a.pdf&code=bdfd9822c124e17308c095f29250a990
 



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.

Re: [time-nuts] PCB for frequency dividers

[Bruce Griffiths]

David C. Partridge wrote:
> I'm going to place an order for the PCB for my frequency divider in the next
> few days.   If I can get a batch of ten ordered the cost will be about USD60
> each plus postage to wherever you are.   PCB is four layer, 5" by 3.5", pads
> will be electrolytic Ni/Au (this house doesn't charge extra for that).
>
>   
Au plating leaves the solder joints vulnerable to the formation of the 
AuSn intermetallic compound which will lead to joint failure.
You may need to remove the Au before soldering.
> The price goes down as the numbers go up of course.   If anyone thinks they
> can better this price, I'm happy to ship the gerbers and NC drill files.
>
> I never did hear back from Magnus about the circuit driving the selectors on
> the '4051, so that stays as it is.
>
> I have one firm request from Norman J McSweyn.
>
> If anyone else would like to order a PCB please could you email me directly
> (rather than on list) at
>
> david dot partridge at dsl dot pipex dot com
>
> I also have a few spare of the '4017 dividers and lots of BAV99 which I'm
> happy to pass on at cost to me.
>
> Cheers
> Dave
>
>
>   
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.

Re: [time-nuts] Thunderbolt Free-running Freq. Offset

[Greg Burnett]

Has anyone established a recommended adjustment window for the Thunderbolt's 
10MHz oscillator free-running frequency? Put another way, does anybody have 
a feel for how far from "nominal 10 MHz" the free-running frequency can be 
before it in some way (if at all) degrades "locked" performance?

I'm assuming that, after power-down, the box looses its 'holdover' memory 
and, upon re-power, reverts to zero hold-over correction? Or does the box 
remember its last hold-over offset correction despite a power loss?

Cheers,
Greg 


___
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] PCB for frequency dividers

[dave powis]

David,

Have you had a look at http://www.top-tec-pcb.com/eng/index_.html?

I use them for my boards, and running a quick estimate using the details you've 
published.  They aren't quite at the price you've indicated, but for a slightly 
higher number they do get significantly cheaper.  There are some items which 
could affect the price that you haven't quoted, such the number of buried vias, 
but you can input all that in their on-line calculator - use the Power-Pool 
quote system, not the prototype quote link.

Regards,
Dave, G4HUP

http://g4hup.com


- Original Message 
From: David C. Partridge <[EMAIL PROTECTED]>
To: Discussion of precise time and frequency measurement 
Sent: Thursday, 24 July, 2008 7:43:23 PM
Subject: [time-nuts] PCB for frequency dividers

I'm going to place an order for the PCB for my frequency divider in the next
few days.   If I can get a batch of ten ordered the cost will be about USD60
each plus postage to wherever you are.   PCB is four layer, 5" by 3.5", pads
will be electrolytic Ni/Au (this house doesn't charge extra for that).

The price goes down as the numbers go up of course.   If anyone thinks they
can better this price, I'm happy to ship the gerbers and NC drill files.

I never did hear back from Magnus about the circuit driving the selectors on
the '4051, so that stays as it is.

I have one firm request from Norman J McSweyn.

If anyone else would like to order a PCB please could you email me directly
(rather than on list) at

david dot partridge at dsl dot pipex dot com

I also have a few spare of the '4017 dividers and lots of BAV99 which I'm
happy to pass on at cost to me.

Cheers
Dave


___
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] Anti-Static conductive foam warning

[Greg Burnett]

Hi Daun & Nigel,

I've experienced the same problem, for example with sliding loads, cal kits 
and other accessories. The trick is to remove all the foam *before* the 
damage is done. Once the deteriorating foam turns to "sticky crumble" and 
reacts with the precision plated metal surfaces in these kits, the surfaces 
can actually become physically pitted and discolored. I could kick myself 
for not staying on top of this and removing the foam sooner in some 
instances.

Next question: Are the manufacturers listening? Or are they still using the 
same foam (that will de-compose in 15 or 20 years).

Greg


Daun wrote:
--clip--
I'm wondering if anyone else who's seen this problem has some advice on a
good way to restore the items.
--clip-- 


___
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] PCB for frequency dividers

[David C. Partridge]

I'm going to place an order for the PCB for my frequency divider in the next
few days.   If I can get a batch of ten ordered the cost will be about USD60
each plus postage to wherever you are.   PCB is four layer, 5" by 3.5", pads
will be electrolytic Ni/Au (this house doesn't charge extra for that).

The price goes down as the numbers go up of course.   If anyone thinks they
can better this price, I'm happy to ship the gerbers and NC drill files.

I never did hear back from Magnus about the circuit driving the selectors on
the '4051, so that stays as it is.

I have one firm request from Norman J McSweyn.

If anyone else would like to order a PCB please could you email me directly
(rather than on list) at

david dot partridge at dsl dot pipex dot com

I also have a few spare of the '4017 dividers and lots of BAV99 which I'm
happy to pass on at cost to me.

Cheers
Dave


___
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] Anti-Static conductive foam warning

[Joseph M Gwinn]

The turning into goo is called "reversion", and is a property of some 
kinds of polyurethane.  There is a good explanation in US patent 4040991, 
and in www.wolaa.org/files/Spring_2007_OHS_-_WOL_In-house_Expertise.pdf . 
It can be difficult to find a solvent for the goo.

As for corrosion causing unsolderability, there is a draconian solution. 
It was a classic story from the 1970s.  We were getting a demo ready for a 
show, and it turned out that the leads on the Nixie tubes had corroded 
enough that they would not take solder.  This is Sunday afternoon.  What 
to do?  I dipped them in dilute sulfuric acid (battery acid cut 3:1), 
rinsed them off in hot water, and then had no problem soldering.  The acid 
dip did not cause subsequent problems, although one could have also used 
dilute bicarbonate of soda to neutralize any traces of acid that survived 
the hot rinse.

Joe Gwinn


[EMAIL PROTECTED] wrote on 07/24/2008 01:38:45 PM:

> Hi Nigel
> 
> I've seen this happen in some other circumstances too, and one of the 
worst
> ones was for VNA Cal kits.  It really makes a mess, and it's 
> pretty hard to clean up.
> I'm wondering if anyone else who's seen this problem has some advice on 
a
> good way to restore the items. 
> It does seem that there are several types of foam (and rubber for that
> matter)
> 
> Daun
> 
> 
> -Original Message-
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
> Behalf Of [EMAIL PROTECTED]
> Sent: Thursday, July 24, 2008 1:12 PM
> To: time-nuts@febo.com
> Subject: [time-nuts] Anti-Static conductive foam warning
> 
> Apologies to those who might see this on more than one group or list and
> apologies again if it's old news to everyone but me, but I did think it
> important enough to share.
> 
> I've just retrieved a pair of ICs that have been dry stored as 
> spares in a
> component storage rack since 1979, a long time I know but probably not
> unusual for those of us using and maintaining older equipment.
> 
> These, as I thought anyway, were correctly stored with the pins pressed
> into black anti-static foam, the usual stuff that's been used for this
> purpose for years.
> Unfortunately the foam has broken down into a sticky crumble and the
> plating on the IC pins is quite badly corroded, probably to the
> point  where
> they won't take solder. A metal canned crystal lying against the foam 
has
> also corroded at the pont of contact.
> I've seen this stuff turn into a gooey mess inside some instrument cases
> but hadn't previously even thought about the same thing  happening where
> it's used used for component storage.
> 
> I've checked other trays and whilst not too many used this 
> stuff but  where
> they did there's evidence of similar problems.
> I've even got a later large component rack, all ok so far but for how
> long?, where it was fitted from new to every drawer:-(
> 
> That's all, just offered as a word of warning to anyone else with
> components similarly stored.
> 
> regards
> 
> Nigel
> GM8PZR
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> ___
> 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] Anti-Static conductive foam warning

[Daun Yeagley]

Hi Nigel

I've seen this happen in some other circumstances too, and one of the worst
ones was for VNA Cal kits.  It really makes a mess, and it's pretty hard to
clean up.
I'm wondering if anyone else who's seen this problem has some advice on a
good way to restore the items. 
It does seem that there are several types of foam (and rubber for that
matter)

Daun
 

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of [EMAIL PROTECTED]
Sent: Thursday, July 24, 2008 1:12 PM
To: time-nuts@febo.com
Subject: [time-nuts] Anti-Static conductive foam warning

Apologies to those who might see this on more than one group or list and
apologies again if it's old news to everyone but me, but I did think it
important enough to share.
 
I've just retrieved a pair of ICs that have been dry stored as spares in a
component storage rack since 1979, a long time I know but probably not
unusual for those of us using and maintaining older equipment.
 
These, as I thought anyway, were correctly stored with the pins pressed
into black anti-static foam, the usual stuff that's been used for this
purpose for years.
Unfortunately the foam has broken down into a sticky crumble and the
plating on the IC pins is quite badly corroded, probably to the point  where
they won't take solder. A metal canned crystal lying against the foam has
also corroded at the pont of contact.
I've seen this stuff turn into a gooey mess inside some instrument cases
but hadn't previously even thought about the same thing  happening where
it's used used for component storage.
 
I've checked other trays and whilst not too many used this stuff but  where
they did there's evidence of similar problems.
I've even got a later large component rack, all ok so far but for how
long?, where it was fitted from new to every drawer:-(
 
That's all, just offered as a word of warning to anyone else with
components similarly stored.
 
regards
 
Nigel
GM8PZR
 
 
 
 
 
 
 



   
___
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] Anti-Static conductive foam warning

[GandalfG8]

Apologies to those who might see this on more than one group or list and  
apologies again if it's old news to everyone but me, but I did think it  
important enough to share.
 
I've just retrieved a pair of ICs that have been dry stored as spares in a  
component storage rack since 1979, a long time I know but probably not  unusual 
for those of us using and maintaining older equipment.
 
These, as I thought anyway, were correctly stored with the pins pressed  into 
black anti-static foam, the usual stuff that's been used for this  purpose 
for years.
Unfortunately the foam has broken down into a sticky crumble and the  plating 
on the IC pins is quite badly corroded, probably to the point  where they 
won't take solder. A metal canned crystal lying against the foam has  also 
corroded at the pont of contact.
I've seen this stuff turn into a gooey mess inside some instrument cases  but 
hadn't previously even thought about the same thing  happening where it's 
used used for component storage.
 
I've checked other trays and whilst not too many used this stuff but  where 
they did there's evidence of similar problems.
I've even got a later large component rack, all ok so far but for how  long?, 
where it was fitted from new to every drawer:-(
 
That's all, just offered as a word of warning to anyone else with  components 
similarly stored.
 
regards
 
Nigel
GM8PZR
 
 
 
 
 
 
 



   
___
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] Watkins Johnson Info

[John Franke]

The 5133 is a YIG Tuned Harmonic Generator designed for an input frequency 
of 500 MHz and an output frequency range of 1.0-12.5 GHz.  Nominal drive is 
1 Watt.  Nominal output power is -13 dbm min.  Tuning coil data: 20 MHz/mA, 
10 Ohms, 100 mH.  Heater:28V, 1A surge, 250mA max steady state.  An external 
bias supply of 0-3V at 300mA max can be used for leveling output power from 
multi-octave units.  Pin-out is unknown.

John  WA4WDL
- Original Message - 
From: <[EMAIL PROTECTED]>
To: 
Sent: Thursday, July 24, 2008 11:04 AM
Subject: [time-nuts] Watkins Johnson Info


> Watkins Johnson produced some excellent microwave oscillators, but their 
> microwave division was sold and resold about a decade ago.  Product 
> information is difficult to find.
>
> I need pin out, product data and/or a link for two of their oscillators.
>
> WJ-5133-3
>
> WJ-5908-79
>
> Thanks,
>
> Stork
>
> ___
> 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] Watkins Johnson Info

[stork3264]

Watkins Johnson produced some excellent microwave oscillators, but their 
microwave division was sold and resold about a decade ago.  Product information 
is difficult to find.

I need pin out, product data and/or a link for two of their oscillators.

WJ-5133-3

WJ-5908-79

Thanks,

Stork

___
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] 32768Hz using DDS

[Chris Cheney]

On 24 Jul 2008 at 8:27, Murray Greenman wrote:

>  and second that the time around the loop is
> changed by the instructions involved in loading.

Well, the timing can be kept constant by always adding in a value.

For the AVR, using a branch to test for overflow is not necessary: ROL 
followed by ANDI will get carry (instead of overflow as we are performing 
unsigned arithmetic) into the bottom bit of a register from where it can 
be used to index for the appropriate value (0 or 52,947) to be added. 

So the relevant calculation can be done with straight-through code, 
without any branches, giving a constant instruction count.

Regards from Cambridge

Chris
G3RSE


___
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.