Chip with simple program for Toy

[Phil Allison]

"Bob Masta"

For most modern amp designs, the curve of distortion versus power
output at 1 kHz looks like a lopsided valley: At very low outputs,
there is moderate crossover distortion, which essentially is a
fixed-size discontinuity near zero so it becomes a smaller percentage
of the total at output power rises. So distortion decreases linearly
until some mid-power region (1-10 watts, say).

** Totally false !!!!!!!!!!!!!!!!!

The characteristic rise in published THD curves at power levels below about
1 watt is almost * entirely * due to supply frequency hum and wide band
random noise.

NOT any mysterious x-over region effects !!!!!!!!!!

The general definition of THD *** includes *** hum and noise - which
tends to be a fixed level at all power outputs.
So the PERCENTAGE increases the signal level reduces !!!

Obvious - right ?

At any rate, the manufacturer has to make a judgement call about
what power level to claim.

** Bollocks.

The typical power output difference between the 0.1% THD level and 0.01%
THD level is trivial for the majority of hi-fi quality SS amps. Maybe 102
watts as compared to 100 watts.

Only by doing THD measurements on * real amplifiers * can one have any
insight into the facts of the matter .

Which I do all the time.

While Bob does not.



....... Phil

 

[Bob Eld]

<mrdarrett@gmail.com> wrote in message
news:9318bf28-99a6-4369-945c-ebb64d28cec0@q10g2000prf.googlegroups.com...

On Apr 9, 11:57 am, mrdarr...@gmail.com wrote:
On Apr 9, 11:20 am, "Bob Eld" <nsmontas...@yahoo.com> wrote:



mrdarr...@gmail.com> wrote in message


news:8b5083e5-4d3e-4117-86d6-a3213396f804@s39g2000prd.googlegroups.com...

Are they serious?

http://av.jvc.com/product.jsp?modelId=MODL027647&pathId=5&page=2
"100 watts per channel, 8 ohms at 1kHz, with 10% THD"

10% THD sounds like a lot.

Michael

It is a lot. Most likely a misprint. Nobody in their right mind would
spec.
an amplifier with that distortion nor would they rate an amplifier at
its
clipping level as has been suggested.

Since getting less than one percent even less than 0.1% THD is trivial
these
days with modern semiconductor circuitry it would seem that this spec
sheet
is probably in error.

Most likely the printer or web master left out a decimal point and
nobody
caught it. Call JVC and ask.

I downloaded the manual, and it also has 10%
THD...http://resources.jvc.com/Resources/00/00/90/LVT1507-001A.pdf

Support info:http://support.jvc.com/consumer/support/index.jsp

I called their 800 number, and heard an amazingly distorted
recording. Maybe distortion is company policy? ;-)

I'll try e-mailing them (but won't hold my breath).

Well, if it does end up a mistake, this would be a pretty good
product...http://www.walmart.com/catalog/product.do?product_id=5301826

Thanks,

Michael


I called them again (the phone lines were clear this time).

Confirmed that, yes, it is 10%. (Tech guy asked his supervisor).

okay then...

Either way, the manual said 8 ohm to 16 ohm impedance only... I was
thinking of using the 4-ohm subwoofer speakers I got (great deal on
car audio) that I currently use on my Onkyo.

Oh well..

"Nobody in their right mind..." ha ha ha.

Thanks guys

M

Well, maybe I should change it to nobody in their right mind would BUY such
a lousy amplifier. You certainly can do better than 10%THD but at what
price, I don't know. This thing might fit your needs if sound quality is not
a big issue.

Four ohms is going to make things worse because if the amp struggles with 8
ohms, 4 will require more current loading the amps even more. However, a
sub-woofer may not care, the speaker will not respond to the higher
harmonics anyway.

In my mind, a bigger issue is intermodulation distortion. If it produces
high harmonic distortion, you can bet it has high IM as well. This is also a
nonlinear distortion and is curiously not even spec'd on the data sheet.
What does that tell you?

 

[Bob Eld]

<mrdarrett@gmail.com> wrote in message
news:9318bf28-99a6-4369-945c-ebb64d28cec0@q10g2000prf.googlegroups.com...

On Apr 9, 11:57 am, mrdarr...@gmail.com wrote:
On Apr 9, 11:20 am, "Bob Eld" <nsmontas...@yahoo.com> wrote:



mrdarr...@gmail.com> wrote in message


news:8b5083e5-4d3e-4117-86d6-a3213396f804@s39g2000prd.googlegroups.com...

Are they serious?

http://av.jvc.com/product.jsp?modelId=MODL027647&pathId=5&page=2
"100 watts per channel, 8 ohms at 1kHz, with 10% THD"

10% THD sounds like a lot.

Michael

It is a lot. Most likely a misprint. Nobody in their right mind would
spec.
an amplifier with that distortion nor would they rate an amplifier at
its
clipping level as has been suggested.

Since getting less than one percent even less than 0.1% THD is trivial
these
days with modern semiconductor circuitry it would seem that this spec
sheet
is probably in error.

Most likely the printer or web master left out a decimal point and
nobody
caught it. Call JVC and ask.

I downloaded the manual, and it also has 10%
THD...http://resources.jvc.com/Resources/00/00/90/LVT1507-001A.pdf

Support info:http://support.jvc.com/consumer/support/index.jsp

I called their 800 number, and heard an amazingly distorted
recording. Maybe distortion is company policy? ;-)

I'll try e-mailing them (but won't hold my breath).

Well, if it does end up a mistake, this would be a pretty good
product...http://www.walmart.com/catalog/product.do?product_id=5301826

Thanks,

Michael


I called them again (the phone lines were clear this time).

Confirmed that, yes, it is 10%. (Tech guy asked his supervisor).

okay then...

Either way, the manual said 8 ohm to 16 ohm impedance only... I was
thinking of using the 4-ohm subwoofer speakers I got (great deal on
car audio) that I currently use on my Onkyo.

Oh well..

"Nobody in their right mind..." ha ha ha.

Thanks guys

M

Well, maybe I should change it to nobody in their right mind would BUY such
a lousy amplifier. You certainly can do better than 10%THD but at what
price, I don't know. This thing might fit your needs if sound quality is not
a big issue.

Four ohms is going to make things worse because if the amp struggles with 8
ohms, 4 will require more current loading the amps even more. However, a
sub-woofer may not care, the speaker will not respond to the higher
harmonics anyway.

In my mind, a bigger issue is intermodulation distortion. If it produces
high harmonic distortion, you can bet it has high IM as well. This is also a
nonlinear distortion and is curiously not even spec'd on the data sheet.
What does that tell you?

 

[amdx]

"John Larkin" <jjlarkin@highNOTlandTHIStechnologyPART.com> wrote in message
news:uqnpv3lvj8n6h3vvhv1dbijcri4ajcfegt@4ax.com...

On Wed, 9 Apr 2008 08:07:10 -0700 (PDT), root114@gmail.com wrote:

1.5 Inch high quality Mini Digital Photo Frame with TF card slot for
up to an amazing 2GB memory. This low cost Digital Frame has a built
in speaker and earphone jack letting you play MP3 music files. This is
a nice little gadget that will let you store your pictures and listen
to music at the same time, and comes with Seriouswholesale no MOQ and
Warrantee Policy.


Welcome to http://www.seriouswholesale.com.


And it comes with wonderful Chinese bonus software!

http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2008/02/15/BU47V0VOH.DTL&type=business

John

I gave one of the Insignia picture frames to my mother, two months later I

got a letter from Insignia telling me the frame could have came with a
virus,
Even if I new how to locate and remove the virus, I'm 1000 miles away
from her computer. ;-(
Mike

 

[Aly]

"qoo" <faizanahmed666@gmail.com> wrote in message
news:d896bc63-127c-4dcb-962c-3ce5f89bcfca@s13g2000prd.googlegroups.com...

Well, its not so simple for me actually. Thats the project I have

Actually, for all concerned (regardless of the homework aspect), I would be
interested in hearing this circuit being explained and discected too?

I've tried building these things in the past and they just don't work.
Stage by stage explanation would be brilliant, as well as design caveats
such as grounding. The issue is that almost all of the radio explanations
out there explain in terms for the complete layman, rather than how to
practically do it right there in front of you and why.

ta.

 

[Aly]

"qoo" <faizanahmed666@gmail.com> wrote in message
news:d896bc63-127c-4dcb-962c-3ce5f89bcfca@s13g2000prd.googlegroups.com...

Well, its not so simple for me actually. Thats the project I have

Actually, for all concerned (regardless of the homework aspect), I would be
interested in hearing this circuit being explained and discected too?

I've tried building these things in the past and they just don't work.
Stage by stage explanation would be brilliant, as well as design caveats
such as grounding. The issue is that almost all of the radio explanations
out there explain in terms for the complete layman, rather than how to
practically do it right there in front of you and why.

ta.

 

[Steven Sullivan]

In rec.audio.tech Michael R. Kesti <michaelkesti@nospam.net> wrote:

"Mr.T" wrote:

snip

I'm sorry, you seem to be under the misapprehension that I was being
serious, or even more deluded into thinking Radium is!
Hopefully you will know better next time

You seem willing to put considerable effort into dissing this person.
Have you considered what this says about you?

Maybe if you were more familiar with 'this person's posting history, you'd
know why.

That history would show you that Mr. Radium is either ill or a troll.
Occasionally interesting discussion arises during the course of
correcting his silly preconceptions, but that's not enough reason to
encourage him.



___
-S
maybe they wanna rock.
maybe they need to rock.
Maybe it's for the money? But That's none of our business..our business as fans is to rock
with them.

 

[Steven Sullivan]

In rec.audio.tech Michael R. Kesti <michaelkesti@nospam.net> wrote:

"Mr.T" wrote:

snip

I'm sorry, you seem to be under the misapprehension that I was being
serious, or even more deluded into thinking Radium is!
Hopefully you will know better next time

You seem willing to put considerable effort into dissing this person.
Have you considered what this says about you?

Maybe if you were more familiar with 'this person's posting history, you'd
know why.

That history would show you that Mr. Radium is either ill or a troll.
Occasionally interesting discussion arises during the course of
correcting his silly preconceptions, but that's not enough reason to
encourage him.



___
-S
maybe they wanna rock.
maybe they need to rock.
Maybe it's for the money? But That's none of our business..our business as fans is to rock
with them.

 

[Bob Eld]

"Eeyore" <rabbitsfriendsandrelations@hotmail.com> wrote in message
news:47FE3D59.1A895B20@hotmail.com...

Bob Eld wrote:

Well, maybe I should change it to nobody in their right mind would BUY
such
a lousy amplifier. You certainly can do better than 10%THD but at what
price, I don't know. This thing might fit your needs if sound quality is
not
a big issue.

I think you're missing the point.

I have little doubt that this amplifier is capable of 0.1% THD at say 60W.

The 10% THD figure has simply been used in order to produce an inflated
power
rating. This is considered normal practice with car audio.

Graham

Yep, apparently that must be the case. However, this isn't car audio. Here's
the device:
http://av.jvc.com/product.jsp?modelId=MODL027647&pathId=5&page=2

Also, can this POS deliver 100 Watts of its distorted power on all five of
it's channels simultaneously? I'll bet not. The rating must be one channel
at a time run for just the few seconds it takes to get a measurement and no
longer.

 

[Bob Eld]

"Eeyore" <rabbitsfriendsandrelations@hotmail.com> wrote in message
news:47FE3D59.1A895B20@hotmail.com...

Bob Eld wrote:

Well, maybe I should change it to nobody in their right mind would BUY
such
a lousy amplifier. You certainly can do better than 10%THD but at what
price, I don't know. This thing might fit your needs if sound quality is
not
a big issue.

I think you're missing the point.

I have little doubt that this amplifier is capable of 0.1% THD at say 60W.

The 10% THD figure has simply been used in order to produce an inflated
power
rating. This is considered normal practice with car audio.

Graham

Yep, apparently that must be the case. However, this isn't car audio. Here's
the device:
http://av.jvc.com/product.jsp?modelId=MODL027647&pathId=5&page=2

Also, can this POS deliver 100 Watts of its distorted power on all five of
it's channels simultaneously? I'll bet not. The rating must be one channel
at a time run for just the few seconds it takes to get a measurement and no
longer.

 

[Aly]

"Michael Black" <et472@ncf.ca> wrote in message
newsine.LNX.4.64.0804101524270.15803@darkstar.example.org...

On Thu, 10 Apr 2008, Rich Grise wrote:

Thanks Michael and Rich

Interesting reading.

In some ways I come from the digital camp where everything is in logical
blocks. Linear stuff just always get's me confused.

Just one question;

The oscillator is the LC tank isn't it?

 

[David L. Jones]

"qoo" <faizanahmed666@gmail.com> wrote in message
news:d896bc63-127c-4dcb-962c-3ce5f89bcfca@s13g2000prd.googlegroups.com...

Well, its not so simple for me actually. Thats the project I have
chosen for this semester. The most basic circuit I have found on
Internet is this:

http://www.electronics-project-design.com/FMTransmitter.html

Please tell me what does BC547 doing here and what is its alternative?
and please do tell me more about that electret microphone. Thanks

Get the Talking Electronics FM bug books:
http://www.talkingelectronics.com.au/shop/index.php/cPath/40?osCsid=bd4ec6d84ef8236ccb8112b5bc31837c
They are not expensive, and explain everything very well.

Dave.

 

[Ray]

"Dave" <db5151@hotmail.com> wrote in message
news:UbCdnYwdEc6mCmLanZ2dnUVZ_gCdnZ2d@internetamerica...

I am trying to use the circuit diagramed in the following schematic as the
source of power in a project I am building, but am apparently missing
something obvious. It provides when the switch is depressed, but the -5V
is always on regardless of the switch position. I have checked and
rechecked, and don’t believe I have anything hooked up incorrectly. Have
also replaced the 7905, without effect. If no one can find anything wrong
with the provided schematic, I am back to square one, and will simply
disassemble and reassemble from scratch to see if that provides any
results. The basic idea for this schematic came from the 7905 datasheet.



Many thanks,

Do you have the same size load on both sides ?

Maybe if the negative side is not loaded, you are reading the charge on the
capacitors

 

[Richard Crowley]

"Green Xenon [Radium]" wrote ...

What characteristics in the film material itself [e.g. the chemicals
within the film, "grains", etc. etc.] determines the audio quality [e.g.
the bandwidth, dynamic range, SNR, clipping point, treble response, etc.
etc.] of a VD track?

Not clear why you would come here asking that question
when it was throroughly documented and published back
before you were born. Are you incapable of doing any
original research on your own?

 

[Joel Koltner]

"Bob Masta" <NoSpam@daqarta.com> wrote in message
news:47fe0425.1356369@news.sysmatrix.net...

At any rate, the manufacturer has to make a judgement call about
what power level to claim.

I've learned recently that speaker manufacturers are similar. The good ones,
when specifiying frequency response, will tell you that it's, e.g.,
100Hz-10kHz at -1dB or -3dB... the less-reputable ones will often spec it
at -20dB !!! ...and of course usually not mention the level.

 

[Dave Platt]

Really? Analog cassette uses sampling?

Basically, yes. See the page at

http://hyperphysics.phy-astr.gsu.edu/hbase/solids/ferro.html

for a description of how ferromagnetic materials (such as are used in
cassette tape) work.

Then, is there any electronic
audio storage device [analog or digital] that does *not* use sampling?
Or is sampling an inescapable monster of everything?

Quantization and uncertainty/noise are pretty much inescapable in this
universe.

Even your beloved variable-density optical sound recording technology
is sampled/quantized, in a way somewhat analogous to the way in which
cassette recordings are.

The film consists of a clear carrier layer, with an impregnated data
layer consisting of discrete particles of metallic silver. The
original film stock was made using particles of silver iodide, which
is photosensitive. When the film is exposed to light and then
developed, those particles of silver iodide which were exposed to
light turn into metallic silver; those which were not exposed, wash
away.

The darkness or optical density of the film strip depends on the
number and size of the silver particles. The apparently-continuous
voltage that creates the sound you hear, is actually related to the
total number of silver particles blocking the light flowing through
the readout mechanism at any given moment of time.

--
Dave Platt <dplatt@radagast.org> AE6EO
Friends of 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!

 

[Dave Platt]

In article <C4252EDC.B4F6C%dbowey@comcast.net>,
Don Bowey <dbowey@comcast.net> wrote:

You *could* sample sufficient points along a analog tape recording to
reconstruct the audio digitally, but that is *not* how audio tape recorders
work.

The recorder creates a varying magnetic field on the moving tape, that is
passing over the recording head. Considering the pre-equalization of the
audio signal, the field is analogous to that audio signal at any moment.

In playback, the magnetic pickup responds to the varying field on the moving
tape by outputting a voltage that is analogous to the changing field. It is
then equalized by a circuit complementing the pre-equalizer.

No "sampling" takes place and nothing digital occurred.

Well, it's "sampled" to the extent that the varying magnetic field,
sensed by the pickup head, consists of the sum of the individual
magnetic fields (vector and magnitude) of the large number of
individual magnetic domains within the ferromagnetic recording layer.

It's not digital, and it's not sampled at regular intervals the way
that a digital-audio or bucket-brigade-chip signal is.

--
Dave Platt <dplatt@radagast.org> AE6EO
Friends of 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!

 

[Bob Masta]

On Thu, 10 Apr 2008 22:51:47 +1000, "Phil Allison"
<philallison@tpg.com.au> wrote:

"Bob Masta"

For most modern amp designs, the curve of distortion versus power
output at 1 kHz looks like a lopsided valley: At very low outputs,
there is moderate crossover distortion, which essentially is a
fixed-size discontinuity near zero so it becomes a smaller percentage
of the total at output power rises. So distortion decreases linearly
until some mid-power region (1-10 watts, say).


** Totally false !!!!!!!!!!!!!!!!!

The characteristic rise in published THD curves at power levels below about
1 watt is almost * entirely * due to supply frequency hum and wide band
random noise.

NOT any mysterious x-over region effects !!!!!!!!!!

The general definition of THD *** includes *** hum and noise - which
tends to be a fixed level at all power outputs.
So the PERCENTAGE increases the signal level reduces !!!

Obvious - right ?

Right. Thanks for reminding me about the hum and noise. It's the same
basic concept I was taliking about: A constant that is a bigger
percentage of a smaller total.

(I'm not sure why you are calling crossover distortion "mysterious"...
I suspect it is the main source of the residual distortion at the
bottom of the valley around 1 watt or so.)

Modern methods using synchronous averaging and FFTs (with a sound card
and the right software... hint, hint!) can measure the distortion
alone, by removing noise and cancelling hum. But I admit it is
purely academic at these low levels, and surely not worth the effort
for most purposes.

At any rate, the manufacturer has to make a judgement call about
what power level to claim.

** Bollocks.

The typical power output difference between the 0.1% THD level and 0.01%
THD level is trivial for the majority of hi-fi quality SS amps. Maybe 102
watts as compared to 100 watts.

I sure won't argue. It depends on how steep the curve is for the amp.
(My suspicion is that this amp may not be in the "hi-fi quality"
department.) At any rate, they must have had *some* reason to pick
the 10% THD point to state their power rating. "100 watts" certainly
would appeal to Marketing better than, say, "97 watts".

Of course, it *could* be a typo. I can just picture Moe telling Larry
"Tenth percent THD" and Larry telling Curly "Ten percent THD". <g>

Only by doing THD measurements on * real amplifiers * can one have any
insight into the facts of the matter .

Agreed!

Which I do all the time.

While Bob does not.

No fair, you peeked! Yes, sad to say that software development has
really been keeping me away from the test bench for far too long.

But I still have my monster dummy load bank (4 x 8 ohms, 200 watts
each) sitting there gathering dust. Some day, Real Soon Now....

Best regards,


Bob Masta

DAQARTA v3.50
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Scope, Spectrum, Spectrogram, FREE Signal Generator
Science with your sound card!

 

[Bob Masta]

On Sat, 12 Apr 2008 13:24:08 GMT, NoSpam@daqarta.com (Bob Masta)
wrote:

<snip>

(I'm not sure why you are calling crossover distortion "mysterious"...
I suspect it is the main source of the residual distortion at the
bottom of the valley around 1 watt or so.)

I just realized that this statement probably marks me as an
out-of-touch dinosaur, since it is based on experiences with bipolar
output devices... now driven to near-extinction by MOSFETs as the
preferred output stage.

"Back in the day", the bias of the output stage was a critical
setting. Too little and the amp ran as class B, with heavy crossover
distortion as the positive and negative devices handed off their share
of the load near 0 volts. So the bias was adjusted for class AB,
where each half carried over just a bit across zero, overlapping with
the other half in a linear region around zero. That way, there was
always somebody there to carry the load. (Still true today, but read
on...)

The problem with bipolars, however, is/was thermal runaway: As they
get hotter, they conduct harder and that causes them to heat up still
more. So you had to be very careful, and have good temperature
compensation for the bias circuit, or the output stage would go up in
smoke. (That's not *absolutely* true: With enough negative feedback
you can get away with pretty meager bias, but there are other problems
with that approach.) I tended to be cautious, and not too concerned
about what I couldn't hear anyway. <g>

But MOSFETs (which I've never used in an output stage) have the
opposite behavior from bipolars: As they heat up, their resistance
goes up and they conduct less, causing them to cool down. So I would
not be at all surprised to find that bias is nowadays set much more
agressively, so that crossover distortion may indeed be a thing of the
past. Mea culpa!

Best regards,


Bob Masta

DAQARTA v3.50
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Scope, Spectrum, Spectrogram, FREE Signal Generator
Science with your sound card!

 

[ronwer]

Then you want to find a copy of "The Invention That Changed the World" by
Robert Buderi), which is about radar development during WWII, but also
about how that need for radar pushed electronics further (and how
that push helped electronics to move along after the war).

Thanks, I will try Amazon!

You have it wrong, silicon diodes weren't used in radar, radar caused
development of semiconductor diodes so they could be used in radar.

They had to use increasingly higher frequencies to get the fine
detail they needed/wanted, and that stretched the limit of vacuum
tubes at the time. Hence they flashed back to the early days of
radio, looked at "cat's whisker" detectors, and compacted that
into more reliable and small devices. Gone were the finicky adjustment
for the hot spot, they got it right once and then sealed it all up.

But, those early diodes were point contact like the cat's whisker
detectors, and as far as I know, they were germanium.

I read the book "The entangled history of silicon" where they mention the
use of silison in diodes for use in radar. The silicon was imported from the
USA (was it from Bell Laboratories? Don't remember right now and I don't
have the book here).

Indeed, those were point contact diodes.

But they were seeing use not as detectors like in "crystal radios"
but as mixers to get the microwave frequencies down to where tubes
could amplify the signals.

It sure seems like you are looking in the wrong direction, expecting
semiconductor diodes to exist before the war, when really the war
caused them to be developed.

No, they existed before the war too, but it was the demand for better radar
(i.e. higher frequencies) that speeded up the development.

See for instance: http://www.avtechpulse.com/faq.html/IX/

Scratch any piece of equipment that did use semiconductor diodes
in WWII, and you are most likely to find that the development of
the equipment involved development of semiconductor diodes.

After the war you see trends moving away from that scenario, where
general diodes were developed independent of specific use, which in
turn caused electronics to move forward which also in turn caused
the need for semiconductors to develop.

The case has been made that the development of the transistor was
based on that work on semiconductor diodes during the war.

What I would be interested in is as follows:

-type numbers of the diodes
-name/type number of radar/communication equipment
-technical infor on those systems
-info on producers
-pictures of actual diodes, also "in" the circuits
-anecdotal stories about the actual use
-anything else!

The information will be used for an on-going study project related to
practical application of minerals (i.e. quartz) in industry and
technology.

So, since this is an aspect of a broader study, other quartz-related info
would
be most appreciated, especially about early use of piezoelectric
quartz crystals in electronic equipment.

Then you've completely missed the one thing that people will think of
when they think "quartz".

Quartz is used in crystals, ie frequency determining elements. Going
back to at least the 1920s. Blanks of quartz sliced thin and then
ground to resonate at a certain frequency. INitially not that much
more than a novelty, then it saw a lot of use, and it continues today,
even though nowadays it's levelled off as frequency synthesis allows
a single crystal to generate multiple frequencies, unlike WWII or even
into the early seventies where you needed a single crystal for every
frequency you wanted to generate (some of that WWII equipment was
loaded with crystals).

Indeed, you don't hear much about quartz used to make semiconductor
devices, so I'm not even sure if your premise on that account is
correct.

Quartz is extensively used in semiconductor devices as isolator between the
individual components.

But I am basically interested in anything related to the use of quartz in
technology, and therefor also in silicon. They belong together.

Thanks for your reply!

Best regards,

Ronald
Norway