audio recording on IC -help wanted

[Al]

On Wed, 19 Sep 2007 11:07:57 -0400, robb wrote:

"Al" <no.spam@wanted.com> wrote in message
news:no.spam-AE4B84.09180019092007@news.verizon.net...
In article <13f0gj12d1e5i1c@corp.supernews.com>,
"robb" <some@where.on.net> wrote:

looking for sn75518N

FWIW, I have heard for people emulating obsolete chips with
microcontrollrs or PALs. I wouldn't be surprised if that's what you
would get if you ordered a significant number of them from an Asian
supplier.

Al

you know after doing all this searching for the chip i was going to ask a
question along those lines but then i thought i would get some feedback like

yea you can with $900 chip burner and $250 programming software, couple of
months microcode/controler development experience and a couple of weeks of
testing and you better buy a tube of chips in case you fry a couple and then
you need a testing board and setup ........

so i did not ask
robb

You're correct. But as a retired engineer and an electronics hobbyist, I
have all that stuff. So far my cache of obsolete parts has kept me
supplied with all the goodies I need so I hadn't needed to do that. People
have been known to put together reasonable chip burners for almost nothing
and use free software to generate their code. I've been fortunate in that
I have the time and patience to do it.

It's much cheaper to buy all the gadgets I make for myself, but there is
the pleasure of the hunt ;-)

Al

 

[timothy ma and constance]

Sir

I am interested the ASIC design on DSP etc

Any good reference to start

THanks

 

[Mark McDougall]

adc-news wrote:

Useful tips and tricks http://windowsxpsp2pro.blogspot.com/

reported as spam to google blogs


--
Mark McDougall, Engineer
Virtual Logic Pty Ltd, <http://www.vl.com.au>
21-25 King St, Rockdale, 2216
Ph: +612-9599-3255 Fax: +612-9599-3266

 

[sandy58]

On Sep 24, 6:41 pm, travolta...@gmail.com wrote:

Repair your system onlinehttp://windowsfreetips.blogspot.com/

Spam.

 

[Steven]

On Sep 24, 9:36 am, Brendan Gillatt
<brendanREMOVET...@brendanREMOVETHISgillatt.co.uk> wrote:

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Green Xenon [Radium] wrote:
On Sep 23, 3:02 pm, Brendan Gillatt
brendanREMOVET...@brendanREMOVETHISgillatt.co.uk> wrote in
http://groups.google.com/group/uk.tech.digital-tv/msg/4c903b0a453a39fa:

Okay now you're actualy irritating me quite a LOT.

How so? I am just asking extremely interesting questions about video
technology.

Please, do yourself a favour: buy an Amazon book voucher and shut up.

I've tried painfully hard to answer my questions doing my own research
-- including reading information from books. I still haven't found
answers to my questions. That is why I am turning to NGs for assistance.

AGGGHHHHH.... plonk

- --
Brendan Gillatt
brendan {at} brendangillatt {dot} co {dot} ukhttp://www.brendangillatt.co.uk
PGP Key:http://pgp.mit.edu:11371/pks/lookup?op=get&search=0xBACD7433
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Version: GnuPG v1.4.3 (MingW32)

iD8DBQFG99mTkA9dCbrNdDMRAku2AJ9kITSaqPsuLn8HsHHYMVvmd06U0wCeJ+lG
1Wjhh/yl5xG0KXs2+xuhUIQ=
=YeLk
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goodbye brendan...have a nice enema

 

[tonsofpcs]

The only way I see of you getting something narrow in bandwidth to
transmit video luma would be to take it, and create a digital system
that has a very large number of discrete states, so large that the
lines between them seem to blur, and transmit it at a very high
frequency (or more, maybe even an ultra high frequency), with a large
number of bits per symbol (8 seems like a good number) but a very high
temporal resolution. You could even modulate a color subcarrier on
and add in chroma information on two axis, lets call them I and Q.
This will create a situation where the receiver will be receiving the
data with interference, but since you are only sending a small amount
of data at each temporal interval, any interference's effect within a
decent area will be negligible and the viewer's eye's will compensate.
On second thought, analog video is so much simpler (and exactly the
same, except it lacks discrete levels).


--
A confused Eric, wondering why you're trying to do this....

 

[Michael A. Terrell]

tonsofpcs wrote:

A confused Eric, wondering why you're trying to do this....

He isn't trying to do anything, other than troll for the gullible.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

 

[LVMarc]

Hello,

Attached is a catalog that covers several families of antennas and ,
integrated active antennas systems;namely a Radiated test Standard and
a Radiated Receiver Standard.

Any feedback that you may have, interest in products or need for
similar but Different;Please contact and Thanks for assistance!

Best regards,

Marc

Link to YT video on FWT

http://www.youtube.com/profile?user=LVMarc

 

[Eric Smith]

Ian, do you have ANY evidence to back that claim re sunlight. AFAICT it is
urban legend, but tests we conducted - in a far sunnier climate than yours
;-) -
revealed not a single bit had changed in 2764's after a month in the
weather.

Should just be a matter of time, given photons as quanta. I couldn't do it
here, light not strong enough, but a less-than-annihilating focus with a
magnifier speeded it up enough to prove I could erase and re-write, so the
question is not whether unfiltered sunlight can do it, it's how long does it
take for a given strength.

It's not just the quantity of photons, but also their frequency, which is
why x-rays won't erase EPROMs. (Sufficient x-ray dose will damage the
part, though.)

The spec is 2537 angstroms, but I think that was selected by Intel because
it was the nominal wavelength from germicidal bulbs. The parts are sensitive
to a range of wavelengths, but I've never seen a response curve.

Natural sunlight doesn't have significant content at or near 2537 angstroms,
or we'd all be blind.

 

[Ian Malcolm]

Lostgallifreyan wrote:

rebel <me@privacy.net> wrote in
news:n93go3tg3rphsfa8d16fdfv0oo30198mvk@4ax.com:


Ian, do you have ANY evidence to back that claim re sunlight. AFAICT it is
urban legend, but tests we conducted - in a far sunnier climate than yours

;-) -

revealed not a single bit had changed in 2764's after a month in the

weather.

rebel

32S 116E



Should just be a matter of time, given photons as quanta. I couldn't do it
here, light not strong enough, but a less-than-annihilating focus with a
magnifier speeded it up enough to prove I could erase and re-write, so the
question is not whether unfiltered sunlight can do it, it's how long does it
take for a given strength.


Lostgallifreyan

51N 238W

Well I was taught many many moons ago, that an EPROM could get wiped by
sunlight and IIRC individual memory cells could be affected in a matter
of weeks of direct sunlight. Of course it would take *much* longer for
the whole EPROM to read blank - especially in our climate.

I *may* still have some of my notes from the time, but they are in dead
tree format and aren't practically searchable (not to mention lousy
handwriting). One thing to bear in mind when setting up such an
experiment is that ordinary window glass is a fairly effective UV filter
and also you need a sunlight recorder (the sort that burn trails accross
the daily paper if you want repeatable results. A lot of work for a
hobbyist for not much knowlage. ONE student engineer probably did some
research back in the early 70's and by the end of that decade, it was
commonly accepted that one *did* cover the windows. Whether later
generations of EPROMS are as vunerable to daylight as say a 1702, is
another matter. I suspect that in the interests of long term data
integrity, later chips may be effectively 'hardened'.

A 1702 datasheet gives the requirements for erasure as shortwave UV
(UVC) at 2537 angstroms with an integrated exposure of 6 watts/sec/cm^2.
UV levels at sea level (tropical) peak at about 0.13 milliwatt/cm^2 at
about 5000 angstroms. UVC is effectively totally removed by the ozone
layer. *IF* UVB was as effective as erasing eproms as UVC, then a 1702
would be totally wiped by 13 hours of direct sunlight. The intesity of
UVC at about 2500 angstrom *outside* the earth's atmosphere is of the
close order of 0.01 milliwatt/cm^2, so an EPROM in *ORBIT* protected
against UVB but *NOT* UVC would be totally erased in 600 hours of
sunlight. Add in the variable effects of cloud cover, strength of the
ozone layer, possible inadequate programming of the EPROM in the first
place, and reduced exposure to flip the first bit rather than wipe ther
whole array etc. I see no reason to doubt that the effective life of the
data in an unprotected EPROM exposed to direct sunlight is of the order
of weeks, not years. One thing is for sure, I am not digging out one of
my remaining few 1702s and breadboarding a programmer to do any tests

I do know that there are confirmed reports of ordinary bench or room
lighting upsetting the operation of windowed EEPROMS and for the price
of a roll of foil tape, one has guaranteed 100% effective light barrier.
I've never experimented with the effect, decapped DRAM with a suitable
lens over it was *much* more interesting!

--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
[at]=@, [dash]=- & [dot]=. *Warning* HTML & >32K emails --> NUL:

 

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not impressed by "golden"
How much do you pay for ideas ?

Robert

 

[msg]

Michael A. Terrell wrote:

jakdedert wrote:

Actually, it's been posited that the use of lead plumbing was one of the
causes of the decline of the Roman Empire. That's just a story I've
heard, and upon what I based my opinion. The truth of it, and the
chemical reaction involved is beyond my experience.

jak



It wasn't lead pipes, it was 'Lead Acetate', a toxic sweetener made
from lead:

<snip>

Wasn't there also a problem with lead-based face makeup both in Rome and
also until modern times?

Michael

 

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[Roger Hamlett]

On Mon, 05 Nov 2007 13:02:35 -0500, John Hudak <jhudak@sei.cmu.edu>
wrote:

Spehro Pefhany wrote:
On Mon, 05 Nov 2007 11:01:27 -0500, John Hudak <jhudak@sei.cmu.edu
wrote:

I am looking for a micro with a 12-bit a/d subsystem on it. I've
searched quite a few mfg, but seems 10-bits is the maximum. Anybody
have any suggestions for microcontrollers that have a 12-bit a/d?
Thanks
John

You didn't look very hard. AD, BB/TI, TI. Silabs, Microchip and
others..

Best regards,
Spehro Pefhany
Actually I did. I have used a few as well..MicroChip, Renseas, Atmel.
Both performance and accuracy is pitiful....
Funnily enough, the 'old' PIC14000, performed very well, on slow

changing signals, and could easily give 14bit accuracy. The current
units can be 'OK', provided you put the processor to sleep for the
conversion, but the way most people use them, you are lucky to get
8bit accuracy.... :-(
It really does depend mssively though on the nature of the signal
involved, and what else is going on round the system. Getting a
genuine 12bits, requires a reference that is better than many, and
significant care in layout. I suspect that most micro designers, are
thinking in terms that with the noise round the processor itself, you
are better off using a small I2C interfaced ADC, that is placed away
from this enviroment, into a 'cleaner' enviroment, and so their
designs are targetted at simplicity, rather than quality. It shows...

Best Wishes

 

[hr(bob) hofmann@att.net]

On Oct 16, 8:04 am, Al <no.s...@wanted.com> wrote:

In article <ff1p89$co...@inews.gazeta.pl>,
"N Cook" <diver...@gazeta.pl> wrote:

at or before pcb assembly.

Does anyone have proven evidence of this and definitely this as cause of
defect , ie not stress cracking of die, internal bond failures etc. Or is it
just a convenient label ?

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

Yes, it really does happen. The leakage current on the input may be
specified as 1 nanoamp or some other value relevent to the geometry or
materials involved. An electrostatic dischange that doesn't distroy the
device may cause the leakage current to jump in the hundreds of
microamps. This current can be easily suppled in most cases by the
driving device. However, in such small structures, a phenomenon called
electromigration can take place. The many microamperes of leakage can
cause metal migration to take place along the leakage path. Eventually
it leads to a sufficiently low resistance that the driving source cannot
supply the current to change the logic state. Then you have a failure.
It may take days or years depending on many factors.

Al

After 44 years at Bell Labs, and head of the Bell Labs EMC Committee
for many years, there are ESD effects at the atom level that lead to
failures in later times, due to disruption of the normal atomic
crystalline (SP?) structure. I wish it wasn't so, but it is.

H. R. (Bob) Hofmann

 

[Dave Plowman (News)]

In article <gNGuj.104665$L%6.67219@bignews3.bellsouth.net>,
jakdedert <jakdedert@bellsouth.net> wrote:

Well there is lead solder in my house and I drink the water. No lead
poisoning yet..

How can you tell? FWIW, I think the ban on lead in plumbing makes a lot
of sense. Still, I'd think that there is very little--if any--lead in
actual contact with the water in a properly sweated joint.

Nor does the lead dissolve in water - lead pipes were in use for hundreds
of years. Of course it may depend on the type of water. Hard water coats
the insides of the pipes.

--
*He's not dead - he's electroencephalographically challenged

Dave Plowman dave@davenoise.co.uk London SW
To e-mail, change noise into sound.

 

[Jim Granville]

Joerg wrote:

Hello Folks,

After some Google searching and perusing the sites of the usual
contenders I only found one uC family that has serious on-chip RF
transceiver capabilities, the Cypress CYWUSB6953 and its brethren.
rfPICs and others usually only have a transmitter.

Anyhow, the Cypress will only serve 2.45GHz but I need the lower UHF
bands for range reasons. Is anything coming down the pike soon or will
that have to remain a two-chip solution?

You've seen the new device from TI ?
Sub GHz and adds USB ?
Part name Frequency Flash RAM USB
CC1110 Sub-1 GHz 8/16/32 KB 1/2/4 KB No
CC1111 Sub-1 GHz 8/16/32 KB 1/2/4 KB Yes
CC2510 2.4 GHz 8/16/32 KB 1/2/4 KB No
CC2511 2.4 GHz 8/16/32 KB 1/2/4 KB Yes

http://www10.edacafe.com/nbc/articles/view_article.php?section=ICNews&articleid=452233

 

[Lostgallifreyan]

Eric Smith <eric@brouhaha.com> wrote in
news:m3sl13q0l4.fsf@donnybrook.brouhaha.com:

Ian, do you have ANY evidence to back that claim re sunlight. AFAICT
it is urban legend, but tests we conducted - in a far sunnier climate
than yours
;-) -
revealed not a single bit had changed in 2764's after a month in the
weather.

Should just be a matter of time, given photons as quanta. I couldn't do
it here, light not strong enough, but a less-than-annihilating focus
with a magnifier speeded it up enough to prove I could erase and
re-write, so the question is not whether unfiltered sunlight can do it,
it's how long does it take for a given strength.

It's not just the quantity of photons, but also their frequency, which
is why x-rays won't erase EPROMs. (Sufficient x-ray dose will damage
the part, though.)

The spec is 2537 angstroms, but I think that was selected by Intel
because it was the nominal wavelength from germicidal bulbs. The parts
are sensitive to a range of wavelengths, but I've never seen a response
curve.

Natural sunlight doesn't have significant content at or near 2537
angstroms, or we'd all be blind.

Irrelevant. It's there, or partial focussing would not be all it takes to get
enough to do it within the few minutes I did it in. So it is just a matter of
time. I know what spectral band it needs, that wasn't the issue here. I'm not
attempting practicality, just saying to those who say it can't happen, that
it can, it's just a matter of how long it would take in unmodifed direct
sunlight. (Too long).

 

[Lostgallifreyan]

Ian Malcolm <valid.address.in.signature@invalid.invalid> wrote in
news:fm98d6$bvp$1@inews.gazeta.pl:

A 1702 datasheet gives the requirements for erasure as shortwave UV
(UVC) at 2537 angstroms with an integrated exposure of 6 watts/sec/cm^2.
UV levels at sea level (tropical) peak at about 0.13 milliwatt/cm^2 at
about 5000 angstroms. UVC is effectively totally removed by the ozone
layer. *IF* UVB was as effective as erasing eproms as UVC, then a 1702
would be totally wiped by 13 hours of direct sunlight. The intesity of
UVC at about 2500 angstrom *outside* the earth's atmosphere is of the
close order of 0.01 milliwatt/cm^2, so an EPROM in *ORBIT* protected
against UVB but *NOT* UVC would be totally erased in 600 hours of
sunlight. Add in the variable effects of cloud cover, strength of the
ozone layer, possible inadequate programming of the EPROM in the first
place, and reduced exposure to flip the first bit rather than wipe ther
whole array etc. I see no reason to doubt that the effective life of the
data in an unprotected EPROM exposed to direct sunlight is of the order
of weeks, not years. One thing is for sure, I am not digging out one of
my remaining few 1702s and breadboarding a programmer to do any tests

Ok, I guess the relative strengths matter rather than the absolute ones (I
was using a magnifying glass). It was a cheap one too, greenish iron-doped
glass. It still worked though. I'll accept that it wasn't the UVC band, but I
think that UVB is enough to do it. It was a Psion Organiser II datapak, and I
managed to get it to be unreadable, and re-'sized' by the Organiser and I
could read its empty capacity and write and read back data from it. The
second time I tried I damaged it to the point where it wouldn't work. While
the safe margin for erasing by focussed sunlight is small, it's there. If
more UVB got to it as a proportion of total light, that margin would be
wider, and it would be possible to set up an exposure meter and timer system.
Pointless, maybe, but it would work.

For the record, I did this test in south UK, early august I think, around
13:30 BST on a day with very clear blue sky, less milky than it usually is
at that time.

 

[Roger Hamlett]

On Fri, 11 Jan 2008 17:44:39 -0800, Eric Smith <eric@brouhaha.com>
wrote:

Ian, do you have ANY evidence to back that claim re sunlight. AFAICT it is
urban legend, but tests we conducted - in a far sunnier climate than yours
;-) -
revealed not a single bit had changed in 2764's after a month in the
weather.

Should just be a matter of time, given photons as quanta. I couldn't do it
here, light not strong enough, but a less-than-annihilating focus with a
magnifier speeded it up enough to prove I could erase and re-write, so the
question is not whether unfiltered sunlight can do it, it's how long does it
take for a given strength.

It's not just the quantity of photons, but also their frequency, which is
why x-rays won't erase EPROMs. (Sufficient x-ray dose will damage the
part, though.)

The spec is 2537 angstroms, but I think that was selected by Intel because
it was the nominal wavelength from germicidal bulbs. The parts are sensitive
to a range of wavelengths, but I've never seen a response curve.

Natural sunlight doesn't have significant content at or near 2537 angstroms,
or we'd all be blind.
I was involved with some tests on EEPROMs, many years ago (back in the

days when the 2716, was 'new' technology).
We had 32 test chips, and put them on the lab windowsill for six
months, without a single bit error.
However we also put another set out in direct sunlight. On these, two
had bit errors after 3 months, and at the end of the test, five showed
errors.
The difference,the glass in the lab windows.
Ordinary glass is quite opaque to the required frequency (253.7nm), so
it is unlikely that chips will get erased in normal room lighting, or
from daylight through windows, but if the unit is outdorrs, the Sun,
does have the energy to cause problems over a long period.

Best Wishes