audio recording on IC -help wanted

[Tim Perry]

It seem I have made an error. I failed to notice this crosposted.


Nope. Lube on fittings is good, as long as one doesn't use axle
grease. The word "lube" is ambiguous here, at best.

Please post a link to your recomended product.

 

[Peto]

On Tue 16 Sep08 04:43, GoldIntermetallicEmbrittlement
<GoldIntermetallicEmbrittlement@youdontknowjack.org> wrote in
<news:l8utc4hatnehh8o59s32ih2e23enih9fn3@4ax.com>:

On Mon, 15 Sep 2008 17:30:23 -0400, "Tim Perry"
timperry@nospammeadelphia.net> wrote:

Likewise any modification or adaptor you add will bear the brunt
of blame in any "discussion" with tech support or field service.

The "techs" that "assist" you online are typically VERY DUMB.

Constant plugging and unplugging of a F connector is not
recommended because the jack is likely to wear out making the
center conductor connection intermittent.

Yes, cable terminations can be very damaging to the female
connectors they mate with.

Most cable companies use a cable with a copper clad center
conductor which is steel. First off, it is very bad for your
side cutters.

The second effect is that the center conductor ends up with a
squared off "nose" (end) that is of a very hard material. This
means that insertion into a female "f" connection WILL badly
abrade on the two spring loaded "wipers" that get pushed aside
by the center conductor when inserted. At that point, the two
wipers become the connection to the center conductor.

Several things happen with this cable type. First, the copper
cladding on it is barely thick enough to even call cladding.
So it wears off, or can wear fairly quickly. But a good hundred
in and outs are likely not a problem

Secondly is the abrasion on those two wipers. They can also
"catch" on the nose of the center conductor and get deformed as
it tries to literally push them out of the way. If the wipers
are SPC (silver plated copper) then the abrasion leading to
poorer performance can be a mere few insertion cycles. If it is
brass or such, it may survive all 100 insertions, and still
yield the same loss.

I have actually tried to round off the nose of my center
conductor before and found it inserted easier. If one has a pure
copper center conductor type cable, wear will not be an issue on
the cable end, but it could still abrade or deform the female
fitting internal parts. I have rounded those ends as well, but
we are talking about severe overkill, considering that one only
desires to insert these things a couple of times in their life.

Very interesting. Thank you.

 

[Peto]

On Wed 17 Sep08 05:04, Michael A. Terrell wrote in
<news:OLOdnXQKjK5CHE3VnZ2dnUVZ_umdnZ2d@earthlink.com>:

Tim Perry wrote:

Please post a link to your recomended product.


http://www.gcelectronics.com/order/SubCatPDF/lubricants%2048-49.
pdf> Part No. 10-2610 Tunerlub is what I've used since the '60s.

I'm the OP. Do you smear Tunerlube on the threads or do you dunk the
plug into it (so the threads and centre connector are both covered in
Tunerlube?)

 

[Tim Perry]

"Michael A. Terrell" <mike.terrell@earthlink.net> wrote in message
newsNudnbwwk_cJcE3VnZ2dnUVZ_uednZ2d@earthlink.com...

Peto wrote:

On Wed 17 Sep08 05:04, Michael A. Terrell wrote in
news:OLOdnXQKjK5CHE3VnZ2dnUVZ_umdnZ2d@earthlink.com>:

Tim Perry wrote:

Please post a link to your recomended product.


http://www.gcelectronics.com/order/SubCatPDF/lubricants%2048-49.
pdf> Part No. 10-2610 Tunerlub is what I've used since the '60s.


I'm the OP. Do you smear Tunerlube on the threads or do you dunk the
plug into it (so the threads and centre connector are both covered in
Tunerlube?)


A very thin film, applied with a Q-tip is all that is needed.

Michael, I'll see you tunerlube and raise you a Molykoat (s)
http://www.dowcorning.com/content/news/iam_news25.asp

However in this application any oil, grease, or any other gunk will attract
dust on both the jack and the plug when they are apart. the resultant
sludge will necessitate cleaning both ends (then we can argue about the best
cleaning solution)

I am not on a mission or crusade or anything. I use cleaners, sealers, etc.
as needed and have for years. My favorite is Caig de-oxit.

Even outdoors for most instillations I find little use for chemicals on F
connectors. Usually tape and a Skotchcoat are sufficient for many years of
faithful service.

Large connectors the story is a bit different. The O-rings on conduit and
coax transmission line should be coated with the silicon paste, usually
supplied with new parts or replacement kits.

In any even I think we have beaten the subject to death.

My recommendation to the Op is get a 4" (100 mm) crescent wrench and place
it on your key ring. It will then be handy for all occasions. Snug the
connector down
and enjoy your high speed access.

 

[Tim Perry]

"Michael A. Terrell" <mike.terrell@earthlink.net> wrote in message
news:9JudnZg0Ua1mLUzVnZ2dnUVZ_orinZ2d@earthlink.com...

Tim Perry wrote:

Michael, I'll see you tunerlube and raise you a Molykoat (s)
http://www.dowcorning.com/content/news/iam_news25.asp


The tunerlube was recommended by the manufacturers back in the '70s &
'80s. We only used it in areas with a lot of salt air that quickly
corroded the connectors. The line taps were shipped with plastic boots
with a thin film of it to seal the threads. When you have over 10,000
outdoor ports, you can't be taking the system down constantly to replace
damaged port connectors.


However in this application any oil, grease, or any other gunk will
attract
dust on both the jack and the plug when they are apart. the resultant
sludge will necessitate cleaning both ends (then we can argue about the
best
cleaning solution)


That is what shop rags were used for. Extra grease when a customer
was disconnected, and wipe it off when reconnected.


I am not on a mission or crusade or anything. I use cleaners, sealers,
etc.
as needed and have for years. My favorite is Caig de-oxit.

Even outdoors for most instillations I find little use for chemicals on
F
connectors. Usually tape and a Skotchcoat are sufficient for many years
of
faithful service.


Try that on a busy highway that got salted every time there was much
snow, or anywhere close to any coastline on either ocean.

My outdoor applications mostly involve satellite dishes. I have a couple
adjacent to the NY throughway. One uses RG 11. Installed for 5 years and no
hint of problems. Most problem I have are with the small offset dishes
where the weather dome points down, drain holes get plugged and it fills
with water.

Large connectors the story is a bit different. The O-rings on conduit
and
coax transmission line should be coated with the silicon paste, usually
supplied with new parts or replacement kits.


The .412", .500", .750" & 1.00" hardline connectors all had o-rings
to keep water out of the amplifier housings, splice blocks, power
inserters and tap housings, but not to protect the threads. Tunerlube
was MUCH easier to clean up than the gelled underground drop cable.

I use up to 3 1/8" coax with close to 30 kW passing through it.
the lines are pressurized to keep moisture out. The o-rings help keep air or
nitrogen in.
Bullets (connectors) are silver plated and are inserted into copper inner
conductors with no chemical additives. The outer conductor (EIA flange) is
connected with bolts. I do use Vaseline on these threads as it makes removal
in the future easier.

 

[TT_Man]

<pcbcore@hotmail.com> wrote in message
news:e8a5ac15-8a82-49d6-aef0-0dc65119be4a@v13g2000pro.googlegroups.com...
On 9ÔÂ18ČŐ, ÉĎÎç3Ęą11ˇÖ, JeffM <jef...@email.com> wrote:

pcbcore@ hotmail.com wrote:
[SPAM] China[SPAM]- Ňţ˛ŘąťŇýÓĂÎÄ×Ö -

- ĎÔĘžŇýÓĂľÄÎÄ×Ö -

We are a professional PCB supplier, JeffM, you don't use our service
before how can you say we are a bad vendor, it's not a responsible
practice, right?
Welcome to our website www.pcbcore.com, only who use it before could
judge us. Thanks.

He's not saying you're bad, just an unwanted email in this newsgroup.......

 

[Hal Murray]

Oh, my god, it's too terrible, I didn't come sci.electronics
groups before and have no idea of it, at the very beginging I just
think it's electronic forum and want to
recommend our company to pcb users, look at what I did, definitely I
am an idiot. I will not do that again.

Even if it was a forum discussing PCBs, you should read it for a while
to get a feel for the group and find out if your announcement would
be welcome.

--
These are my opinions, not necessarily my employer's. I hate spam.

 

[TT_Man]

">>> We are a professional PCB supplier, JeffM, you don't use our service

before how can you say we are a bad vendor, it's not a responsible
practice, right?
Welcome to our website www.pcxxxxxx.com, only who use it before could
judge us. Thanks.
You are judged by your spamming a _non_sale_ newsgroup.
That makes you an a-social creep.

FFS get a life.
People whinging about on-topic product announcements are far more annoying
than the messages that
caused them.

I agree....

 

[TT_Man]

"JeffM" <jeffm_@email.com> wrote in message
news:f7596b63-2cd1-49af-98cd-5a2ce5dd0f1d@k30g2000hse.googlegroups.com...

JeffM wrote:
This vendor has showed you he has the ethics of a sewer rat
and the business acumen of an 8 year old

pcbcore @hotmail.com wrote:
JeffM, before I post, I even don't know what's the usenet,

I already covered your cluelessness.
Your ignorance is NOT a valid excuse for spamming.

[...]we are not clueless parasite, we are not sewer rat,

Your behavior indicates otherwise.
Your FIRST instinct was to SPAM. You clearly are a cheater.
Since you don't *naturally* know how to conduct yourself,
I suggest you enroll in a course in Business Ethics.
Make sure it covers the topic
"Advertising is a cost of business--just like rent and utilities".

As the subject of proper behavior seems foreign to you,
perhaps you will need to start with a course in Personal Ethics.

I even don't understand what's the meaning that you say
"It's called a sig and *that* is acceptable."

I suggest, before you post to any place on the Internet again,
that you MAKE THE EFFORT to find out.
...and a sig wouldn't make any difference in your case anyway;
you have NOTHING of value to post to this group.

In addition, find out what exactly consitutes "SPAMMING".
It appears what passes for acceptable behavior in China
is VERY different from the rest of the world.
...or maybe I'm wrongly accusing a culture
and it's just that there are thoughtless creeps like you everywhere.

You're a pig ignorant git, and worse than the original poster. May god
forgive you at the pearly gates.. What's worse is you hide behind an
anonymous email address, yet you complain that the OP posted behind the
same. Let him who casts the first stone springs to mind.
Go and crawl back under your stone.

 

[TT_Man]

"> So, to review:

This vendor has showed you he has the ethics of a sewer rat
and the business acumen of an 8 year old
yet you think it's a good idea to tie the fortunes of your venture
to these clueless parasites.
When your boards show up late and wrong
and they try to charge you more than the estimate,
remember this day.

I use a pcb supplier from China......more than 10k boards in 2 yrs.
They've never been late
They've never been wrong
They've never tried to charge more
They're certainly not clueless
They're certainly not parasites
They have always been polite and courteous, which is something you have yet
to grasp. You really are a sad person. What has made you so bitter and
twisted?
I've never looked back

 

[Anonymous]

On Mon, 22 Sep 2008 17:35:59 +0100, The Natural Philosopher <a@b.c>
wrote:

Not your mate, you retarded fuck. This is Usenet. Keep your
localized retarded colloquialisms to yourself, fuckhead.
And no... it was most certainly you that is getting pissed
on.

Ah, foul language. The last resort of those who know they've lost the argument (and the plot in this case).

 

[Borked Pseudo Mailed]

On Wed, 24 Sep 2008 15:38:58 GMT, mymail@hotmail.co.uk wrote:

On Wed, 24 Sep 2008 07:49:36 -0700, GoldIntermetallicEmbrittlement
GoldIntermetallicEmbrittlement@youdontknowjack.org> wrote:


Not your mate, you retarded fuck. This is Usenet. Keep your localized
retarded colloquialisms to yourself, fuckhead. And no... it was most
certainly you that is getting pissed on.
Keep your totally utterly disgusting expletives to yourself also just
because this is Usenet it doesn't mean that we all have been brought
up in the gutter .

In my country, asshole... I enjoy free speech.

Feel free to stand under the shower with you ASSociate.

Well in this country it's *arsehole* not asshole. Why would
anyone want to converse with an orifice of a donkey?

 

[Jerry G.]

What you are asking would be dependent on the grade crystal materials that
they select for manufacturing them. The crystals have a thermo, and internal
pressure coefficient factor to deal with. They are also a bit voltage
sensitive, as in part of the feedback circuit employed in the design of the
oscillator that they are part of.

For home computers, they do not need to use an expensive high stability type
crystal, as such that is used for precision instrumentation. I would not be
surprised if the clocking frequency in a home PC machine is drifting about
1% to 2%. As long as everything keeps properly synchronized there will be no
problem, no matter what the master clocking frequency is.

The time keeping crystal in a PC is different from the one used for the main
system. The actual real time clock is a separate operation. It is read by
the main system, only at the times where it needs to get the time of day,
and the date data. The time of day accuracy of most computers is about the
same as any low cost quartz watch. I found the time of day on most computers
to drift as much as several minutes a month, if not corrected. A typical
Timex or Casio watch can do better than 15 seconds per month.

There are softwares available to re-set the clock automatically from some of
the various time standard services around the world. I believe that XP comes
with such a software. This can be done over the internet.

If you have the budget you can install a GPS time standard system, and
install the hardware and software in your computer to work with it. The GPS
antenna would have to be installed at a location where it can clearly see
the sky to receive the GPS satellite data. This type of installation would
result in the most possible accurate time of day standard for a PC computer.

--

Jerry G.
=====

<Sunwaesh> wrote in message
news:4217077d$0$1023$afc38c87@news.optusnet.com.au...
Is there any published research/report about how much "uncertainity" and/or
variations must be expected on a PC clock frequency ?

 

[mc]

The specifications of the crystal will tell you.

For home computers, they do not need to use an expensive high stability
type
crystal, as such that is used for precision instrumentation. I would not
be
surprised if the clocking frequency in a home PC machine is drifting about
1% to 2%. As long as everything keeps properly synchronized there will be
no
problem, no matter what the master clocking frequency is.

That would be a gigantic drift for even a very cheap crystal. I think
1/10,000 is more typical of what would be a large drift from a low-quality
crystal.

 

[Joerg]

Hello Sunwaesh,

If it is a modern PC or laptop keep in mind that clock frequencies are
often purposely dithered. That way the spectral energy spreads and the
manufacturer often gets around an EMC nightmare.

Regards, Joerg

http://www.analogconsultants.com

 

[Robert Scott]

On Sat, 19 Feb 2005 18:38:17 -0000, dplatt@radagast.org (Dave Platt)
wrote:

The PPS pulses are infrequent enough, and subject to enough jitter,
that the drivers will need to do a fairly significant amount of
low-pass filtering before using the pulse information to calibrate the
internal clock.

Not true. You can buy a GPS receiver that produces 1 PPS with hardly
any jitter at all. By using a PLL, a high-quality frequency standard
can and has been made. You don't need a lot of low-pass filtering in
that PLL.



-Robert Scott
Ypsilanti, Michigan
(Reply through this forum, not by direct e-mail to me, as automatic reply address is fake.)

 

[Dave Platt]

The PPS pulses are infrequent enough, and subject to enough jitter,
that the drivers will need to do a fairly significant amount of
low-pass filtering before using the pulse information to calibrate the
internal clock.

Not true. You can buy a GPS receiver that produces 1 PPS with hardly
any jitter at all. By using a PLL, a high-quality frequency standard
can and has been made. You don't need a lot of low-pass filtering in
that PLL.

Well, from what I've heard and read... it depends.

For one thing, different GPS receivers have different amounts of
jitter in their PPS pulses. Some (e.g. the Oncore series) are quite
good, while others have a larger amount of variation in timing. This
seems to be due to software/firmware design in the GPS receivers'
controllers. In his discussion on GPS-disciplined oscillators at the
site I mentioned, Brooks Shera notes that many GPS receivers' PPS
pulses are too jittery to use as a source for PLL-disciplining a good
oscillator.

For another thing... most PCs don't have special-purpose PLL or other
capture hardware to "catch" the exact timing of the PPS signal.
Simple approaches usually seem to involve hooking up the PPS line to a
parallel-port pin, to a serial-port CD pin, etc. and generating an
interrupt. The interrupt service routine then captures the
processor's high-resolution clock value. With most operating systems,
there can be a large amount of jitter in the time needed to enter the
ISR, depending on what other interrupt or kernel activity is taking
place. If your PC is down deep in the network card's interrupt
service routine and is handling heavy amounts of packet traffic, it
could require many microseconds, or in some cases a millisecond or
more, to enter the serial/parallel port ISR and sample the CPU clock.
This source of jitter is likely to be much greater than the jitter in
the GPS PPS pulse itself.

Since the original poster asked about the timing error "between PPS
pulses" and didn't mention the use of special-purpose low-jitter
capture hardware, my guess is that this CPU/OS-induced jitter may very
well be relevant to the problem.

--
Dave Platt <dplatt@radagast.org> AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

 

[Robert Scott]

On Sat, 19 Feb 2005 20:09:32 -0000, dplatt@radagast.org (Dave Platt)
wrote:

The PPS pulses are infrequent enough, and subject to enough jitter,
that the drivers will need to do a fairly significant amount of
low-pass filtering before using the pulse information to calibrate the
internal clock.

Not true. You can buy a GPS receiver that produces 1 PPS with hardly
any jitter at all. By using a PLL, a high-quality frequency standard
can and has been made. You don't need a lot of low-pass filtering in
that PLL.

Well, from what I've heard and read... it depends.

For one thing, different GPS receivers have different amounts of
jitter in their PPS pulses...

I agree. I tried to make a high-quality frequency standard using a
Sandpiper GPS receiver. The 1-PPS output was very low jitter on one
edge but very high jitter on the opposite edge. Probably a flip-flop
was being reset by software. I started out using the wrong edge and
couldn't understand why my loop was so unstable. When I switched to
the other edge, then everything worked out fine. This was
special-purpose hardware, not just a digital input pin on a PC, so I
agree also that unless you have special-purpose hardware, you really
can't do much with that low-jitter pulse.


-Robert Scott
Ypsilanti, Michigan
(Reply through this forum, not by direct e-mail to me, as automatic reply address is fake.)

 

[Richard Freeman]

<Sunwaesh> wrote in message
news:4217214a$0$1998$afc38c87@news.optusnet.com.au...

Jerry G.,

Thank you for your valuable answer.
In a project I need to have time synchronization between a set of
computers where some of them are networked together on a LAN (no internet)
and some others are running stand alone. I am planning to use the
one-pulse-per-second (1PPS) signal from the GPS receivers. The networked
computers will have one GPS receiver and all the other stand alone
computers will have their own GPS receivers. GPS receivers will generate
1PPS signals to interrupt the computers to set their internal time clocks.
Applications will use the computer timer (get the time of the day). I want
to model (some how, but I do not know how) the probable variation that a
computer clock may have between 1PPS signals.

Would anyone comment/argue/recommend/suggest/propose how one can model the
variation on a PC clock frequency ?

The Answer is that without knowing a whole lot of Factors (temperature of
the crystal oscillator, specs of the oscillator etc) it is not easy to model
or estimate the accuracy of a PC's internal clock beyond 'adequate for most
scenarios' If accuracy is required a better clock is required.

The Clock source from the GPS (if properly locked and implemented by the GPS
manufacturer) should be close to a Cesium clock in terms of accuracy and
will be several orders of Magnitude ( around 1 part in 1*10^12) better than
the clock from the PC which will be around 100 Parts per million if the
Temperature is kept constant at around 25c

A few links FYI
http://www.beaglesoft.com/stsystarcardspecs.htm#StarSync
http://www.gpsclock.com
http://www.aelcrystals.co.uk/

 

mc wrote:

surprised if the clocking frequency in a home PC machine is
drifting about
1% to 2%. As long as everything keeps properly synchronized there
will be

That would be a gigantic drift for even a very cheap crystal. I
think
1/10,000 is more typical of what would be a large drift from a
low-quality
crystal.

The battery-powered RTC clock is frequently VERY inaccurate, though.
For reasons I've never had explained to me, they almost always have a
trimcap on that xtal. Their Q/C processes to set that trimcap appear to
be FUBAR.