audio recording on IC -help wanted

"Lostgallifreyan" <no-one@nowhere.net> wrote in message
news:Xns9C58BC96325ABzoodlewurdle@216.196.109.145...
If you always do everything the 'right' way, how are you going to learn
anything for yourself?
I don't really see a connection there. Certainly there's plenty to be learned
from applying ICs such as the LM317 in unorthodox ways, but there's also
plenty to be learned from studying the "right" way to solve a specific
problem. Indeed, often the "new" right way comes about from someone
experimenting with the old ways and having a flash of insight.

I'm all for people experimenting and figuring out interesting new applications
for circuits originally designed for different applications, but I'm also all
for examining the works of the likes of Phil and Joerg and Jim since they have
a demonstrated track record of building rock-solid designs.

In a hobbyist environment, one should certainly try out whatever wild ideas
pop into their heads. In a work environment, while engineerins shouldn't
generally be discouraged from trying out wild ideas :), they need to be
prioritized based on the perceived risk, time/resources needed to experiment,
other project priorites, etc. I've seen firsthand someone's clever idea
costing lots of money because the idea turned out to have unforeseen
limitations -- any time you're proposing something wildly different from the
traditional approaches, be sure to budget for plenty of testing time. On the
other hand, you have John's company, where many of his products are completely
unique based on his ability (and his employees') to successfully incorporate a
few wild new ideas into viable products.

---Joel
 
On Thu, 30 Jul 2009 10:59:27 -0700, Joerg <invalid@invalid.invalid>
wrote:

John Larkin wrote:
On Thu, 30 Jul 2009 10:10:50 -0700, Joerg <invalid@invalid.invalid
wrote:

John Larkin wrote:
On Wed, 29 Jul 2009 12:32:03 -0700, Joerg <invalid@invalid.invalid
wrote:

Lostgallifreyan wrote:
[...]

While I found that a string of four 1N4148's produced a modelled overshoot
almost exactly like what I saw on an oscilloscope months before I considered
looking at spice, I got a very different result when trying four 1N4001's so
it really does need something better than reaching for a standard diode, in a
model OR as a dummy diode in a real circuit (where a optically dead laser
diode is best anyway). So it really comes down to trying to get something
usefully close! EDN's model seems ideal, aimed at solving this problem for
general use, as opposed to the elaborate models in private university
publications. EDN's is probably tested too, proofread and verified before
publishing.

http://www.e-insite.net/ednmag/archives/1998/071698/pdf/15di.pdf
(Halfway through file).

"File not found" :-(

Some of the 4000 series behave more like PIN diodes.
The higher-voltage ones ARE pin diodes. They can make excellent drift
step-recovery diodes and impact avalanche diodes. Need 1000 volts in
100 picoseconds?

Do you have some examples and pics? That would be interesting, I have
use the 1N4007 as a RF PIN diode but never as SRD.

Google "Grehkov diode". He's a Russian guy who discovered the DSRD and
impact avalanche effects in cheap power diodes.

Also look for papers and patents by Thomas E. McEwan.


Thanks, I will check that out.


We did one water-cooled DSRD pulser that makes -2KV pulses, about 2 ns
wide, at 500 KHz. We forward-bias a secret diode at +48 volts for
about 80 ns, to let the current build up to 50 amps or so, then
reverse-bias it from a 400 volt supply and wait for it to snap.

Here's the pulser head...

http://www.highlandtechnology.com/DSS/T220DS.html

with the serious parts bolted to a gold-plated copper block. A
water-flow cold plate gets bolted to the bottom.

I can show you innards privately. The HV, high power PIN diode turned
out to be unusual.


That would be nice. My "Reply to" address is valid as is and lands in my
biz inbox. But only if you feel comfortable doing that.

Was this the project from several years ago that started with the FR804?
Yes. We did wind up with a reel of FR804's that snap nicely, maybe
decent PIN diode material, but we went to a bigger part in the end,
higher voltage and more power dissipation.

It was fun, but we only sold a few.


Take a look at this puppy, fresh out of the gate:

http://www.nxp.com/acrobat_download/datasheets/BYV29FX-600_1.pdf

In the project coming up I need a lot more volts though (10kV range) and
it has to be small.
You should probably use real RF power PIN diodes, like
Skyworks/Microsemi/Aeroflex. They have doping profiles that give
absurdly long recovery times, so it takes very little DC to control a
lot of RF. I used exotica because I needed a huge amount of power
dissipation capability when we were running at 500 KHz.

John
 
"Joel Koltner" <zapwireDASHgroups@yahoo.com> wrote in
news:3Wlcm.493461$6p1.334514@en-nntp-02.dc1.easynews.com:

I don't really see a connection there. Certainly there's plenty to be
learned from applying ICs such as the LM317 in unorthodox ways, but
there's also plenty to be learned from studying the "right" way to solve
a specific problem. Indeed, often the "new" right way comes about from
someone experimenting with the old ways and having a flash of insight.
That's exactly how I improve code when I write it, I look at what aorks best
and always revisit to see if there;s a further improvement because there
often is. But there is also context. In several posts here I've accounted for
the context of my decision to try this LM317 wheeze. There's no reason not to
try it, and a few good ones to try it.
 
Tim Williams wrote:
"Lostgallifreyan" <no-one@nowhere.net> wrote in message
news:Xns9C585A893Dzoodlewurdle@216.196.109.145...
Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote in
news:58CdnWEqNIuvS-3XnZ2dnUVZ_vBi4p2d@supernews.com:

snivet

żQué?

Wow, I didn't know people were still using that term. Last time I heard it
was in talking about tube televisions from the 1960s!

Snivets is where the sweep output tube undergoes oscillations (Barkhausen
oscillation) between the plate and screen, when plate voltage is lower than
screen (Vp(sat) typ. 30V for these types, at Vg2 = 125V). It's supposed to
make an electron-beam-driven resonant cavity, producing UHF oscillations
something like a klystron I suppose. The solution is to raise the voltage
on the beam former grid to about 30V.

Can I get a modern definition for "snivets"?

"Sniveling Idiot". ;-)


--
You can't have a sense of humor, if you have no sense!
 
On Fri, 24 Jul 2009 04:01:01 -0500, Lostgallifreyan
<no-one@nowhere.net> wrote:

Lostgallifreyan <no-one@nowhere.net> wrote in
news:Xns9C512D9705DE7zoodlewurdle@216.196.109.145:

Definitely a communications breakdown spreading here but I'm not entirely
sure it's electro-optical in nature..


Does anyone here know how to adapt a diode model for a laser diode?
For an all but clueless first cut i think you would need a four
terminal device, to include the transport of emitted photons.
 
"JosephKK"<quiettechblue@yahoo.com> wrote in
news:3e7o75h7m29qpd1ca55o00bl96ivfn6msq@4ax.com:

On Fri, 24 Jul 2009 04:01:01 -0500, Lostgallifreyan
no-one@nowhere.net> wrote:

Lostgallifreyan <no-one@nowhere.net> wrote in
news:Xns9C512D9705DE7zoodlewurdle@216.196.109.145:

Definitely a communications breakdown spreading here but I'm not
entirely
sure it's electro-optical in nature..


Does anyone here know how to adapt a diode model for a laser diode?

For an all but clueless first cut i think you would need a four
terminal device, to include the transport of emitted photons.
Yes, I was sent an Intusoft newsletter that contained just such an animal,
but it's based on a Hitachi 3mW IR diode, I think. But as a 'dead' diode with
facet damage from ESD or other surge usually behaves very similarly to a live
fresh one, electrically, AND most high power diodes have no monitor
photodiodes anyway, there's nothing wrong with only two terminals. What is
then critical, if it's to be driven hard, is to include temperature
monitoring in the model. In practise diodes will vary but the setting will be
a set-and-forget one based on a single measurement of power at maximum drive,
once the thermal compensator works. I did this once (before I ever looked
into spice) using an LM317 and some thermistors in the sense resistance
network. It sounds crude, but I calculated it in some detail, and it worked
well. Apart from that LM317, the entire driver was discrete passive parts.
(Wasn't modulated though, have to add stuff then.)
 
Martin Musatov wrote:
snipped stuff, lots of it..

Lostgallifreyan wrote:
Wow. As in 'Why'? And perhaps, WTF?
You noticed the cross-posting; this was also multi-posted.
This spammer is a 1-trick pony:
http://groups.google.com/groups/search?enc_author=VH8HkCUAAABao2jumPzMV4lt0Ss00ePnixa6E0eetrkPH3BIwN2wzDNkEozqbodaZ7xQDlJcpTo&scoring=d
You might drop a note to
mailto:abuse@arcor-ip.de abuse@ arcor-ip.de
 
JeffM <jeffm_@email.com> wrote in
news:7c779e0e-c1cf-4f05-8f9e-6a8207be1d99@q7g2000yqi.googlegroups.com:

Martin Musatov wrote:
snipped stuff, lots of it..

Lostgallifreyan wrote:
Wow. As in 'Why'? And perhaps, WTF?

You noticed the cross-posting; this was also multi-posted.
This spammer is a 1-trick pony:
http://groups.google.com/groups/search?enc_author=VH8HkCUAAABao2jumPzMV4l
t0Ss00ePnixa6E0eetrkPH3BIwN2wzDNkEozqbodaZ7xQDlJcpTo&scoring=d You might
drop a note to mailto:abuse@arcor-ip.de abuse@ arcor-ip.de
If it happens again, I will. I didn't do more than delete it this time,
because if it happens again I want to know. Most times I let it pass, just
filter it out because spam is rarely interesting.
 
Lostgallifreyan wrote:
"Martin Musatov http://MeAmI.org 'Search for the People!'"
marty.musatov@gmail.com> wrote in
news:26ca7d88-05c8-4592-bebf-b02e17cd8e80@o9g2000prg.googlegroups.com:

snipped stuff, lots of it..

Wow. As in 'Why'? And perhaps, WTF?
I'm local to the spammer, & I've sent off a complaint to his/her university.

--
W
. | ,. w , "Some people are alive only because
\|/ \|/ it is illegal to kill them." Perna condita delenda est
---^----^---------------------------------------------------------------
 
Lostgallifreyan wrote:
Bob Larter <bobbylarter@gmail.com> wrote in
news:h8j5ev$963$7@blackhelicopter.databasix.com:

Progressive Architecture Girl wrote:
Patrick Jost, an award-winning architect based in Melbourne,
Australia, commented on the continued notoriety of Pruitt-Igoe:
I'm also based in Melbourne, Australia, & I don't have the faintest idea
what this spam has to do with repairing electronic equipment.
OTOH, I do have a couple of friends who work for Melb Uni, so I might
ask them what they think of you spamming.

HTH!


:)
They top the surrealometer, if nothign else. Although a couple of posts today
have kept it high. Cross-posted to alt'slack. LOL, didn't even know that
existed. :) Cut me some... three pipes full if you please.
Melb Uni have promised me that they're going to do something about their
spammer.


--
W
. | ,. w , "Some people are alive only because
\|/ \|/ it is illegal to kill them." Perna condita delenda est
---^----^---------------------------------------------------------------
 
Bob Larter <bobbylarter@gmail.com> wrote in
news:h8n0jl$8dt$2@blackhelicopter.databasix.com:

Lostgallifreyan wrote:
Bob Larter <bobbylarter@gmail.com> wrote in
news:h8j5ev$963$7@blackhelicopter.databasix.com:

Progressive Architecture Girl wrote:
Patrick Jost, an award-winning architect based in Melbourne,
Australia, commented on the continued notoriety of Pruitt-Igoe:
I'm also based in Melbourne, Australia, & I don't have the faintest
idea what this spam has to do with repairing electronic equipment.
OTOH, I do have a couple of friends who work for Melb Uni, so I might
ask them what they think of you spamming.

HTH!


:)
They top the surrealometer, if nothign else. Although a couple of posts
today have kept it high. Cross-posted to alt'slack. LOL, didn't even
know that existed. :) Cut me some... three pipes full if you please.

Melb Uni have promised me that they're going to do something about their
spammer.
Cool, nice if you have someone responsive to talk to. Last time I tried it
was like dropping money into an oubliette and calling it a wishing well. :)
Not that oubliettes aren't cool, in a sinister kind of way.
 
On Fri, 2 Oct 2009, Bill wrote:

Hi,

Does anyone know of stereo earphones with a connector with four
conductors? (ie., they don't share the ground node). I would like to
drive them in a bridge-tied load (BTL) configuration, to save the
coupling capacitors.

Thank you

And then you end up with not being able to use just any headphones simply
because you don't want the capacitor. Headphones are the thing that's
likely to break first, and you've ended up with a situation where the user
will then end up not being able to use the gizmo since they have to order
the headphones from some single source in New Jersey.

I have a headphone jack on the car radio that I use as a bedside radio. I
put the capacitor on it so I could use a single output of the car radio to
feed the headphones. I sure didn't need the extra power of balanced
output, and the capacitor was hardly "large". You should have been around
forty years ago, then a 10,000uf capacitor at 17v was the size of a coke
can. Now, it's not any extra size.

Since this sort of thing is dealt with all the time in commercial
equipment, you've made the issue more complicated than necessary. They
live with the usual headphones, and thus they must live with the "nasty"
output capacitor. On the other hand, my Sansa Fuze is small enough that
there must be miniscule capacitors at the needed capacitance, since all of
the unit complete with batteries and LCD screen is jammed in that tiny
package.

Michael
 
On Fri, 2 Oct 2009 10:43:38 -0400, Michael Black <et472@ncf.ca> wrote:

Since this sort of thing is dealt with all the time in commercial
equipment, you've made the issue more complicated than necessary. They
live with the usual headphones, and thus they must live with the "nasty"
output capacitor. On the other hand, my Sansa Fuze is small enough that
there must be miniscule capacitors at the needed capacitance, since all of
the unit complete with batteries and LCD screen is jammed in that tiny
package.
No, they must not live with the output capacitors. You can avoid them
with a dual supply (or with charge pumps if you run from an explicit
single supply). I'd bet that's what they do in tiny MP3s, etc.

It's only that I don't want to use noisy circuits like charge pumps,
and I don't have a dual supply.

Best
 
On Sun, 11 Oct 2009 14:26:54 +0200, brute wrote:

!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"
<snip>

Posting to Usenet in HTML is *NEVER* awesome.

--
"Electricity is of two kinds, positive and negative. The difference
is, I presume, that one comes a little more expensive, but is more
durable; the other is a cheaper thing, but the moths get into it."
(Stephen Leacock)
 
On 23:10 9 Nov 2009, Arno wrote:

mike <not@here.invalid> wrote:
Rounding IDE cables this looks as if it could cause electrical
problems on the PATA cables. Is it really as safe as he
suggests it is?

http://cpu-central.com/Articles.asp?article_id=7249&
decor_int=27

Depends. With UDMA 3 or before you can get data corruption. I
had this with a burner that did not support data checksums on
UDMA 3. Most HDDs do suuport these checksums, but the standard
does not require it before UDMA 4. For all UDMA levels you can
get command corruption, checksums on commands are not present
before SATA.

It also depends on lenght. My experiences are (If I remember
correctly): 30cm - works, 45cm - data corruption with the
burner, 60cm - command problems with HDDs, 90cm - basically
unusable with HDDs being dropped by the kernel within minutes.
Cable quality can influence that in both directions.

Arno
The home made mod doesn't seem to have as much protection from
intereference.

Ready made rounded PATA/IDE cables arrange the wires (signal and
ground) as twisted pairs.

Don't know how much difference this makes.
 
Hi!

Vince wrote:
On 23:10 9 Nov 2009, Arno wrote:

mike <not@here.invalid> wrote:

It also depends on lenght. My experiences are (If I remember
correctly): 30cm - works, 45cm - data corruption with the
burner, 60cm - command problems with HDDs, 90cm - basically
unusable with HDDs being dropped by the kernel within minutes.
Cable quality can influence that in both directions.

The home made mod doesn't seem to have as much protection from
intereference.

Ready made rounded PATA/IDE cables arrange the wires (signal and
ground) as twisted pairs.

Don't know how much difference this makes.
Actually, a lot. Therefore, creating "home-made" ATA cables from
ordinary ATA cables is not a very good idea.

Best regards,

Iggy
 
Vince wrote
Arno wrote
mike <not@here.invalid> wrote

Rounding IDE cables this looks as if it could cause electrical problems
on the PATA cables. Is it really as safe as he suggests it is?

http://cpu-central.com/Articles.asp?article_id=7249&decor_int=27

Depends. With UDMA 3 or before you can get data corruption. I
had this with a burner that did not support data checksums on
UDMA 3. Most HDDs do suuport these checksums, but the standard
does not require it before UDMA 4. For all UDMA levels you can
get command corruption, checksums on commands are not present
before SATA.

It also depends on lenght. My experiences are (If I remember
correctly): 30cm - works, 45cm - data corruption with the
burner, 60cm - command problems with HDDs, 90cm - basically
unusable with HDDs being dropped by the kernel within minutes.
Cable quality can influence that in both directions.

The home made mod doesn't seem to have as much protection from intereference.
True, but neither did the original 40 wire cables either.

Ready made rounded PATA/IDE cables arrange the wires (signal and ground) as twisted pairs.
Some do, some dont.

Don't know how much difference this makes.
Not much.
 
On 08:58 10 Nov 2009, Rod Speed wrote:

Vince wrote
Arno wrote
mike <not@here.invalid> wrote

Rounding IDE cables this looks as if it could cause
electrical problems on the PATA cables. Is it really as safe
as he suggests it is?

http://cpu-central.com/Articles.asp?article_id=7249&decor_int
=27

Depends. With UDMA 3 or before you can get data corruption. I
had this with a burner that did not support data checksums on
UDMA 3. Most HDDs do suuport these checksums, but the
standard does not require it before UDMA 4. For all UDMA
levels you can get command corruption, checksums on commands
are not present before SATA.

It also depends on lenght. My experiences are (If I remember
correctly): 30cm - works, 45cm - data corruption with the
burner, 60cm - command problems with HDDs, 90cm - basically
unusable with HDDs being dropped by the kernel within
minutes. Cable quality can influence that in both directions.

The home made mod doesn't seem to have as much protection from
intereference.

True, but neither did the original 40 wire cables either.

Ready made rounded PATA/IDE cables arrange the wires (signal
and ground) as twisted pairs.

Some do, some dont.

Don't know how much difference this makes.

Not much.
My impression is that the 80-way PATA cables were a big improvement
on the old 40-way cables. Does anyone know of any data or tests
which shows how much improvement they gave?

In this thread Igor Batinic says twisted pair is quite an
improvement over untwisted. Does anyone know of any tests or
comparisons for this?
 
Vince Inscribed thus:

On 08:58 10 Nov 2009, Rod Speed wrote:

Vince wrote
Arno wrote
mike <not@here.invalid> wrote

Rounding IDE cables this looks as if it could cause
electrical problems on the PATA cables. Is it really as safe
as he suggests it is?

http://cpu-central.com/Articles.asp?article_id=7249&decor_int
=27

Depends. With UDMA 3 or before you can get data corruption. I
had this with a burner that did not support data checksums on
UDMA 3. Most HDDs do suuport these checksums, but the
standard does not require it before UDMA 4. For all UDMA
levels you can get command corruption, checksums on commands
are not present before SATA.

It also depends on lenght. My experiences are (If I remember
correctly): 30cm - works, 45cm - data corruption with the
burner, 60cm - command problems with HDDs, 90cm - basically
unusable with HDDs being dropped by the kernel within
minutes. Cable quality can influence that in both directions.

The home made mod doesn't seem to have as much protection from
intereference.

True, but neither did the original 40 wire cables either.

Ready made rounded PATA/IDE cables arrange the wires (signal
and ground) as twisted pairs.

Some do, some dont.

Don't know how much difference this makes.

Not much.

My impression is that the 80-way PATA cables were a big improvement
on the old 40-way cables. Does anyone know of any data or tests
which shows how much improvement they gave?

In this thread Igor Batinic says twisted pair is quite an
improvement over untwisted. Does anyone know of any tests or
comparisons for this?
The primary point of using 80 conductor cables was impedance matching to
reduce the standing waves at the high data rates. It makes little or
no difference whether they are twisted or not. Theoretically twisting
should improve interference rejection, but I suspect that it would be
very difficult to quantify.

Rolling the cable into a tube or using twisted pairs in a tube, probably
would have some effect on the air circulation inside the case. Doing
smoke tests don't show any real advantage over flat ones. The case
design has to be really poor, like some of the "Philips" machines I've
seen where the thing is so cramped the air circulation is almost nil.

--
Best Regards:
Baron.
 
In comp.sys.ibm.pc.hardware.storage Vince <spamtrap@invalid.com> wrote:
On 08:58 10 Nov 2009, Rod Speed wrote:

Vince wrote
Arno wrote
mike <not@here.invalid> wrote

Rounding IDE cables this looks as if it could cause
electrical problems on the PATA cables. Is it really as safe
as he suggests it is?

http://cpu-central.com/Articles.asp?article_id=7249&decor_int
=27

Depends. With UDMA 3 or before you can get data corruption. I
had this with a burner that did not support data checksums on
UDMA 3. Most HDDs do suuport these checksums, but the
standard does not require it before UDMA 4. For all UDMA
levels you can get command corruption, checksums on commands
are not present before SATA.

It also depends on lenght. My experiences are (If I remember
correctly): 30cm - works, 45cm - data corruption with the
burner, 60cm - command problems with HDDs, 90cm - basically
unusable with HDDs being dropped by the kernel within
minutes. Cable quality can influence that in both directions.

The home made mod doesn't seem to have as much protection from
intereference.

True, but neither did the original 40 wire cables either.

Ready made rounded PATA/IDE cables arrange the wires (signal
and ground) as twisted pairs.

Some do, some dont.

Don't know how much difference this makes.

Not much.

My impression is that the 80-way PATA cables were a big improvement
on the old 40-way cables. Does anyone know of any data or tests
which shows how much improvement they gave?
Look into the standard. They made UDMA speeds of 66MHz and above
possible by adjusted impedance and inter-wire shilding. It is
not so much about a better cable as one adjusted to what you
intend to send over it.

In this thread Igor Batinic says twisted pair is quite an
improvement over untwisted. Does anyone know of any tests or
comparisons for this?
That is historic by now. Look into any undergraduate text on
signal transmission.

Arno

--
Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno@wagner.name
GnuPG: ID: 1E25338F FP: 0C30 5782 9D93 F785 E79C 0296 797F 6B50 1E25 338F
----
Cuddly UI's are the manifestation of wishful thinking. -- Dylan Evans
 

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