HDTenEightyP/NetNews huggingface dataset:
From: corey@sdf.lonestar.org (Corey Carroll)
Subject: Need help with LM628 *fast*
Organization: Best lil' ol' Pubnix in Texas
Date: Thu, 19 Nov 1992 06:25:49 GMT

Hello.  I am working on a project that will let me get my
associates degree in Electronics Technology here at a local
community college.  I am using the LM628 to control a dc motor.
I asked National Semiconductor for one, and they sent me one for
free (thanks NS!).  However, I have no documentation on the chip.
What I need most is instructions on how to program the chip.  I
am getting some idea of how to do it from the article I am
working with.  It has a simple C listing showing how to set up
the filter parameters, load in the velocity and acceleration
data, and start the trajectory.  Could anybody enlighten me more
on this chip?  Email me your answers.

-- 
corey@sdf.lonestar.org  214-296-0458   Corey Carroll
Newsgroups: sci.electronics
From: tjfs@tadtec.uucp (Tim Steele)
Subject: Re: Rugby clock code receivers - help ?
Organization: Tadpole Technology plc
Date: Fri, 20 Nov 1992 19:53:51 GMT

Incidentally, Comet/Argos have a speaking digital clock radio which
sets itself from Rugby for UK#40.

Tim
From: gjw@dcs.glasgow.ac.uk (Mr Garry J. Wardrope)
Newsgroups: sci.electronics
Subject: Re: does dbuV = uV ???
Date: 23 Nov 92 11:59:38 GMT
Organization: Glasgow University Computing Science Dept.

jronnau@kuhub.cc.ukans.edu writes:

>dBuV is a logarithmic-relative measure defined as follows:

>     dBuV = 10*log10( x uV / 1 uV)
>          where x is the voltage in microvolts.

>This relationship yields:
>     1 uV => 0 dBuV
>     2 uV => 3 dBuV
>    10 uV => 10 dBuV
>   100 uV => 20 dBuV

>dBuV is a nice shorthand way of describing wide dynamic range measurments.

>Jim Ronnau
>JRONNAU@KUHUB.CC.UKANS.EDU

This is not  actually correct the factor of 2 is missing.  The correct
story is as doherty@melpar (Kevin Doherty)  writes:

> dbuV = decibels referred to one microvolt; ie, 0 dbuV = 1 uv; 20 dbuV is
>10 uV; 40 dbuV = 100 uv; 60 dbuV = 1 mV; etc.  dbuV = 20 log (volts)
>


  Bels are the log of a power ratio and decibels are 10ths of a bel.

i.e.	value in decibels is 10 * log(p1/p2)

	p2 is your reference power.  There are various standards used depending
on what you are measuring (e.g. threshold of hearing for sound levels).

   As we all should know power is proportional to voltage squared so
the ratio is then (v1/v2) squared  This is the same as multiplying the log by 2
so the formula becomes:

	value in decibels is  20 * log(v1/v2)

   The actual value depends not only v1 but v2 if we choose v2 as 1 uV then we
have:

	value in decibels reference 1 uV (dbuV) is 20 * log(v1/1uV)
or
	value in decibels reference 1 uV (dbuV) is 20 * log(v1 uV)



  Hope this clears up any confusion over the slightly differing explanations
given previously.


		Garry
-- 
Mail:	Garry Wardrope, Computing Science Dept.,  Tel: (041) 339 8855 x5322
	Glasgow Univ., 17 Lilybank Gardens, Glasgow G12 8QQ, UK. 
email:	gjw@dcs.glasgow.ac.uk
".. and even if I came in sight of paradise what price its moon without Marsco"
From: kingpin@mole.gnu.ai.mit.edu (Joe Smooth)
Newsgroups: sci.electronics
Subject: WANTED: Startek handheld frequency counter
Date: 23 Nov 92 21:16:48 GMT
Distribution: sci
Organization: None

I am looking for a Startek handheld frequency counter (specific
model number not available) which as the LED display and signal strength bar
graph.. If you have one for sale which has the previous two characteristics,
please reply, and maybe it is the model I am looking for! Thanks!
From: vbreault@rinhp750.gmr.com (Val Breault)
Newsgroups: sci.electronics
Subject: Re: The My Idea Clause, was Big NASTY RS
Date: 23 Nov 92 16:29:30 GMT
	<1992Nov20.203319.27826@u.washington.edu>
	<1992Nov21.123652.12396@phx.mcd.mot.com>
Organization: General Motors Research Labs
In-reply-to: schuch@phx.mcd.mot.com's message of 21 Nov 92 12:36:52 GMT

In article <1992Nov21.123652.12396@phx.mcd.mot.com> schuch@phx.mcd.mot.com (John Schuch) writes:
   In article <1992Nov20.203319.27826@u.washington.edu> pollock@milton.u.washington.edu (Joe Pollock) writes:
   >
   >     It appears that Tandy/Radio Shack lays claim to anything [an employee]
   >may>develop, even on [his] own time, that may be in any way related to [his]
   >employment at Radio Shack.  

   Here at Motorola, we are required to sign a very simular document upon
   employment (somewhere inbetween the interview and the 'whiz quiz') Even
   the janitors and cafeteria people have to sign. I guess the corporation
   wants to make sure they have every right the 'Left Handed Ergonomic
   Semi-Automatic Mop Wringer/Pail With Attached Lunch Box.'

   How many other companies out there require this?

I believe that it's pretty standard fare and nothing to get really
excited about.  They basically want to have first crack at potential
patents, but aren't really interested in anything that isn't a part
of their core business.  Motorola probably requires it from the janitors
because requiring it of one class of employee and not of another may
seem prejudicial.   I'm sure that they would not be interested in
persuing a patent on that example.

I work part time for RS and if the forms were taken literally, I can not
do programming work at home for GM Research or for ANY other employeer.
I cannot even do contract programming.  I really gave them a hard time
over that one.  We finally came to a mutual agreement (sigh!).
--
-val-

Val Breault - GM Research - vbreault@gmr.com - N8OEF            \      /|
Instrumentation dept., 30500 Mound Rd., Warren, MI 48090-9055    \    / |
The opinions expressed by the author do not necessarily reflect   \  /__|
those of GMR or those of the General Motors Corporation.           \/   |___
 

Newsgroups: sci.electronics
From: bacarlso@silver.ucs.indiana.edu (Brad Carlson)
Subject: Caller ID
Organization: Indiana University
Date: Thu, 19 Nov 1992 07:20:47 GMT

I was wondering if anyone has seen any plans for Caller ID units?
If not, anyone know of a good source for production units?  What features 
should I look for.  Anything I should avoid?  

Thanks in advance ...

Brad
From: cstadbg@csv.warwick.ac.uk (Mr M J Brown)
Newsgroups: sci.electronics
Subject: Electronics Sale
Date: 16 Nov 92 15:51:13 GMT
Distribution: eunet
Organization: Computing Services, University of Warwick, UK
NNTP-Posting-Host: lily.csv.warwick.ac.uk


ELECTRONICS STOCK CLEAROUT

27C64 New Normally 3.65 - Yours (2.00 pounds) or 10 for 18.00 pounds
27C512 New 5.95 Normally - Yours (3.00 pounds) or 10 for 25.00 pounds
27C64 Programmed/Erased once only (1.50 pounds)
27C512 Programmed/Erased once only (2.50 pounds)

8087 Math Co processor (8087-2) 8 MHZ Intel .. 89.00 pounds originally but
I will sell for 60.00 pounds (Brand New .. with manual, only fitted once to
my ageing and incompatible PC)

All above is new (except where stated) - add 2.00 pounds UK postage or for
Europe add 5.00 pounds (any size order). Mail me for further details, or if
I do not reply within four days, post into this newsgroup. I will see it.

=============================================================================  
     _/      _/   _/   _/  _/   _/_/_/_/   |
    _/_/  _/_/   _/   _/_/     _/          |         Michael Brown
   _/  _/  _/   _/   _/       _/_/         |
  _/      _/   _/   _/_/     _/            |   cstadbg@csv.warwick.ac.uk
 _/      _/   _/   _/  _/   _/_/_/_/  _/   |
=============================================================================
From: Larry_Hawkins@amwbbs.rain.com (Larry Hawkins)
Newsgroups: sci.electronics
Subject: 50/60Hz problem?
Date: 19 Nov 92 08:11:56 GMT
Article-I.D.: amwbbs.Larry_Hawkins.01iz
Distribution: world
Organization: The Amiga Connection BBS (503)667-5852

I will be going to Hungary for an extended period of time soon, and was
wondering what do do about the power difference. I can get a 900 watt
Auto-Transformer for under a hundred dollars, but I'm not sure what the
effect of 50 cycle power will be?? I assume the Amiga will just autoboot in
PAL mode, but what about the monitor, I have an original 1080 monitor, 16
MHz Amiga 3000 and a Dallas Fax 14.4 FaxModem. Hopefully I will be able to
use this over there, If anyone 'Over There' has any info, it would be
greatly appreciated!
          
                         Thanks, Larry Hawkins

BTW - You can reply here, or E-Mail to this address or my account at
Portland State University (pr059@psuorvm)

-- Via DLG Pro v0.985b
Newsgroups: sci.electronics
From: doherty@melpar (Kevin Doherty)
Subject: Re: 555timer/flasher
Organization: E-Systems, Melpar Division
Date: Tue, 17 Nov 1992 12:03:36 GMT

  that is a circuit i have memorized:
                    
                                           vcc
                                            |
                             +----------+   |      
                      +------+ 1      8 +---+---/\/\/-+       
                      |      |          |   |    r2   |
                      | +----+ 2      7 +---|---------+
           d1    r3   | |    |          |   |         |
         +-|>|--/\/\/-|-|----+ 3      6 +---|-+-/\/\/-+
         |       +----|-+    |          |   | |  r1
         |       |    | | +--+ 4      5 +-x | |
         |     --+--  | | |  +----------+   | |
         |     --+--  | | +-----------------+ |
         |    c1 |    | +---------------------+            
         +-------+----+                                    
                      |                                     
                    -----                                  
                     ---                                   
                      -                                    

  it works by charging c1 to 2/3 vcc through r1+r2, then discharging c1 to 
1/3 vcc through r1 alone.  don't recall the r1/r2/c formulas offhand, but
you should be able to figure them out from the above.
  notice also: the duty cycle is set by the ratio of r1 to r1+r2.  you can't
quite get a 50% duty cycle, although you can get close.  (actually with some
circuit mods one can get any duty cycle desired)
Newsgroups: sci.electronics
From: toddi@mav.com (Todd Inch)
Subject: Re: Tube primer?
Organization: Maverick International Inc.
Date: Thu, 19 Nov 92 21:20:57 GMT

In article <1992Nov14.073048.5200@weyrich.UUCP> uunet.uu.net!weyrich!orville writes:

>Note -- the above looks a lot like a collector-coupled NPN transistor
>circuit also -- emitter is like cathode
>		base is like grid
>		collector is like plate.

Except applying voltage to the grid decreases current flow from the cathode
to plate while applying current to the base of a NPN (BJT) increases the
collector-emitter current.  So, a tube works more like an FET from a practical
standpoint.

I believe the europeans used to (still?) call tubes "valves" since they limit/
allow the flow of current.  Hence the reference designator "V" on schematics.

It's been awhile since I've thought about this!
Newsgroups: sci.electronics
From: Ed_Meyer@mindlink.bc.ca (Ed Meyer)
Subject: Re: police laser radar
Organization: MIND LINK! - British Columbia, Canada
Date: Fri, 20 Nov 1992 19:26:26 GMT

> Galen Watts writes:
>
> Msg-ID: <Nov16.225043.36767@yuma.ACNS.ColoState.EDU>
> Posted: Mon, 16 Nov 1992 22:50:4
>
> Org.  : Environmental Science and Technology Center
>
> When talking about IR, generally you speak of wavelength, not frequency.
> Looking at a handy catalog, the only one I can find uses a wavelength of
> 788nm.
>
> If the police LIDAR systems use commonly available IR LaserLEDS, you could
> fit a few around the front of your car so a cop in any position in front of
> you
> sees at least ond diode.  Modulate the power supply with a little noise
> (like
> ignition noise) and the officer won't be able to get a reading that makes
> any
> sense to his machine.
>
> If your source is brighter than the reflection of the officer's source.
>
> If they find the system on your car, say it is your garage door opener.
>
> Better yet, if you're a ham, it's an experimental radio device, since hams
> can
> use any freq above 300 GHz.
>

Just a quick question: is the >300 GHz area open to Hams in Canada?

     Ed Meyer

Newsgroups: sci.electronics
From: "Gary A. Woodward" <p00140@psilink.com>
Subject: IC lithography and manufacture.
Organization: Performance Systems Int'l
Date: Sat, 21 Nov 1992 14:03:44 GMT
X-Mailer: PSILink (3.2)

Ihave an idea.  I am sorry but I am not too technical with electronics(I 
have a degree in econ-probably the best if more economists would find 
something other to do also:)).  Is there a source that will tell me the 
basics on micro etching of items such as the lithography that allows IC 
circuts to be made?  I am looking specifically for 5-20 micrometer 
resolution. What would the cost of such equipment be-even used obsolete
equipment would work.  The wafers would not to be clean room quaility.
Would it be possible to make these micro etched items in my basement?
I can not discuss now-but after patent pending I will be willing to discuss.


thanks very much in advance.


GW
From: jeh@cmkrnl.com
Newsgroups: sci.electronics
Subject: Re: Tracking the position of a diode in 3space
Date: 19 Nov 92 09:47:46 GMT
Organization: Kernel Mode Consulting, San Diego, CA

In article <1992Nov18.010237.6001@ole.cdac.com>, ssave@ole.cdac.com 
(The Devil Reincarnate) writes:
> In article <1durunINNc91@coyote.cs.ubc.ca> harrison@cs.ubc.ca (James Harrison) writes:
>>
>>We have an application for the tracking of the position of a person in
>>a larger room with little or no hardware carried by the person being
>>tracked.  What we would ideally like to do is know the position of the
>>person in a large room (x, y).
>>
>>Anyone done this?  Know it can/can't be done?
> 
>   Try the IR movement detectors. A sharp enough definition would give an X-Y-Z
> position if the three detectors were placed on two adjacent walls and the ceiling.

I don't believe that this will work.  According to what I've read about these
devices, they contain just one IR pickup.  Therefore they can't tell where
anything is, even in a single dimension.  They can only tell that something is
moving, somewhere, across their field of "vision". 

How it works:  The IR detector is placed behind a curved Fresnel lens.  The
lens divides the field into in-focus and out-of-focus areas. As an IR source
moves across the field, the IR detector "sees" alternating high and low levels
of IR. 

A simple high-pass filter (with cutoff at a few Hz or so) and pulse detector
does the rest.  They aren't sensitive to stationary heat sources, or slow-
moving ones like the sun, because these do not generate pulses fast enough,
or at all. 

	--- Jamie Hanrahan, Kernel Mode Consulting, San Diego CA
Internet:  jeh@cmkrnl.com, hanrahan@eisner.decus.org, or jeh@crash.cts.com
Uucp:  ...{crash,eisner,uunet}!cmkrnl!jeh
From: miller@hmsp04.wg3.waii.com (Griff Miller X7114)
Newsgroups: sci.electronics
Subject: Speaker level to line level
Date: 18 Nov 92 18:29:17 GMT
Distribution: usa
Organization: Western Geo. - Div of Western Atlas Intn'l Inc., Houston, TX
Originator: miller@hmsp04.wg3.waii.com

Hi. Some time back I asked for some help converting the speaker-out leads
on a car stereo (that doesn't have line-level-out jacks)
to the line-level-in jacks on a car power amp. I received some email back
(thanks!) that told me that some resistors were all need to convert the
signal down to a level that the power amp could accept.

So, does anyone know what size resistors I should use?
--
Griff Miller - miller@monarch.wg3.waii.com
My opinions are mine, not Western's.
"The fear of the Lord is the beginning of knowledge, but 
fools despise wisdom and discipline."   - Proverbs 1:7
From: smckinty@sunicnc.France.Sun.COM (Steve McKinty - Sun ICNC)
Newsgroups: sci.electronics
Subject: Re: Secam to Pal
Date: 17 Nov 1992 18:19:22 GMT
Organization: SunConnect
Distribution: world
NNTP-Posting-Host: hardy.france.sun.com
Keywords: Video

In article <1992Nov17.161717.2694@acri.fr>, pjhicks@hard03.acri.fr (Peter J. Hicks) writes:
>  Is there anybody out there that knows how to transcode Secam to Pal ?
>  
>  Are there chips available that do this function or is it a matter of building a mass of logic 

Its not logic chips you need, the signals are analogue so you need
analogue conversion circuitry. Usually means decoding it to RGB and
re-encoding it.

I have a catalogue from a UK company which sells SECAM to PAL transcoders,
I can't remember the price but I can check.
> 
>  if  so,  hows about a circuit diagram.
> 
>   Final question  What is the difference between  Secam and Pal ?

When colour TV systems were designed they had to be compatible with
Black&White ones, so they couldn't send the three colour signals (RGB)
separately. Instead several systems were developed to transmit a normal
monochrome picture, with the colour signal squeezed in, in such a way that
a mono TV would ignore it but a colour one could get it.

Since the black & white image (L) is R+G+B, you don't need to send
all three colours, just two is enough. By sending L, R and B the set
can recalculate G as L - (R+B). Monochrome sets use the L signal and
ignore the rest.

NTSC combines the R and B signals into one extra signal which is transmitted
on every line of the picture. That takes fairly complex circuitry to extract
the separate R & B, but it means that all three signals (L, R, B) are always
available so getting R G & B on each line is then fairly easy. Unfortunately
the NTSC colour signal is vulnerable to distortion (green faces) so
Telefunken, in Germany, modified the NTSC signal slightly to reduce that
effect, and the result is PAL.

 
SECAM sends R on one line, B on the next. That simplifies things a bit
since you don't need to separate the R and B signals, but does require
the TV to have a delay line (analogue memory) to store the colour signal from
one line so it can be combined with the other colour on the next line.
(SECAM = SEquential Couleur Avec Memoire)

At the time it was developed (early 60's) delay lines were expensive
and since PAL doesn't need one it was more popular in most countries, except
France (where SECAM was invented).  Nowadays delay lines are really cheap
and even PAL decoders use them to counteract colour changes caused by
signal distortions.


Steve

-- 
Steve McKinty
SUN Microsystems ICNC
38240 Meylan, France
email: smckinty@france.sun.com	   BIX: smckinty
Newsgroups: sci.electronics
From: wellsc@CS.ColoState.EDU (christopher wells)
Subject: HELP!! Applied Spectrum Technologies Modem
Date: Sat, 21 Nov 1992 02:33:49 GMT
Organization: Colorado State University, Computer Science Department






Hello,

A friend of mine recently purchased a 19.2k baud modem at a flea-market.
Two problems, it didn't come with a manual, it's not Hayes compatible.

The maker is Applied Spectrum Technologies, Inc. and what I beleive to
be a model number is DVM-400.

If anyone out there in net-land knows how to get a hold of this company
or knows anything about this modem (i.e. command sets, etc.), this
information would be GREATLY appreciated.

Thanks in advance,

Chris
wellsc@cs.colostate.edu 

Newsgroups: sci.electronics
From: cmwolf@mtu.edu (christopher m. wolf)
Subject: Re: Reading and Writing IBM pc parallel port
Organization: Michigan Technological University
Distribution: sci.electronics comp.periphs
Date: Sun, 15 Nov 1992 15:58:30 GMT

We hooked an A/D and a D/A to the same printer port on a 286 last
year.  There is a place in memory (don't ask me anymore) that gives
the address of the memory controlling the pins to lpt1,2,etc.  We
just used ML to write directly to the pins, and read directly back
from them.  There are just enough pins for input and output, that you
can drive both.  We had nothing left over.
Newsgroups: sci.electronics
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: Help! Converting 2400 to 9600 baud.
Date: Sat, 21 Nov 1992 21:35:40 GMT
Organization: U of Toronto Zoology

In article <1992Nov17.174405.44889@kuhub.cc.ukans.edu> 2hujpapaw@kuhub.cc.ukans.edu writes:
>Has anyone ever had any luck (or ever tried for that matter) converting
>a 2400 baud modem to 9600 baud?  I have heard that it can be done fairly
>easily by replacing a few key IC's...

This is like saying that you can convert your VW Rabbit to a Ferrari by
jacking up the front and rear bumpers and changing a few key parts in
between.
-- 
MS-DOS is the OS/360 of the 1980s.      | Henry Spencer @ U of Toronto Zoology
              -Hal W. Hardenbergh (1985)|  henry@zoo.toronto.edu  utzoo!henry
From: root@cibbs.UUCP
Newsgroups: sci.electronics
Subject: Re: Help! Converting 2400 to 9600 baud.
Date: Sat, 21 Nov 92 22:08:24 EST
Reply-To: uunorth!cibbs!root
Organization: DataSoft Consulting (Toronto, Ont. Canada)

2hujpapaw@kuhub.cc.ukans.edu writes:

> 
> Has anyone ever had any luck (or ever tried for that matter) converting
> a 2400 baud modem to 9600 baud?  I have heard that it can be done fairly
> easily by replacing a few key IC's.  I will try to get the text file to
> do it if anyone is interested.


I have that text file. Damn thing is a sham! DO NOT DO IT! You'll destroy your
modem in the process. It should be noted that 9600bps modems V.32 compatible
with V.42bis and MNP1-5 are now about CAN$320.

Though I have not tried the info in the text file, I know people that have and
ended up buying a new modem.

Mark

----
Club InSaNiTy BBS   |   BBS:+1 416 691 0679 |   root@cibbs.UUCP
DataSoft Consulting | Voice:+1 416 691 5529 |   uunorth!cibbs!root
Mark Buckaway       | Toronto, Ont. CANADA  |   1@4653 (WWIVnet)
Newsgroups: sci.electronics
From: ollis@redbck.stl.dec.com (Stephen Ollis)
Subject: Can this be done?
Reply-To: ollis@redbck.stl.dec.com (Stephen Ollis)
Organization: Digital Equipment Corporation
Date: Mon, 23 Nov 1992 23:26:12 GMT


I do some concert production work in my spare time, and I have a large 
task ahead of me in about 12 days ... The gig we are putting on requires 
a choir of around 200 people.. Now the stage manager and the asst. stage
manager
will not be able to molly coddle these people, and there aren't going to be
enough stage hands to `herd' them into the right place at the right time...
I thought that maybe a system like the following would be of use, but I can't
figure out how to implement it... 

Stage manager has a jiffy box that has 8 lit pushbutton switches, with a socket
for a cannon microphone lead in the side of it. Each station has a cannon in
and a cannon out socket, and a couple of hi intensity LED's. Each station has a
hard-set id #. When the stage manager presses the button on the master, the 
correct station lights up. The stations would be daisy chained together, with
the master at the head of the link.

_________              Room1                   Room2            etc, etc
| MASTER|
--------- <---------> +--------+
                      | Slave1 |
                      +--------+ <---------> +--------+
                                             | Slave2 |
                                             +--------+ <-- etc etc..
When button 1 is selected, ONLY slave1's LED's comes on. When button 2 is 
selected, slave2's LED's come on. Slave1 doesn't need to be selected for Slave2
to light up. 

Power supply is anything up to 18V at the master. Cannon lead has 3 wires, so 
I thought +ve, -ve, and signal could be handled on the one mic lead. The signal
could be a binary signal (?) with bits set for each station. 

Am I barking up the wrong tree? is this possible? Apart from very basic stuff,
I have very little experience here (I'm just the computer graphics bod, the
electronic stuff I'll hand to someone else)  Any pointers to adaptable circuits
or ideas would be really appreciated.. Our normal techs are unavailable so I'm
in it up to my eyes!!!!

--
DIGITAL Telephone Support, Sydney AUSTRALIA   *   Ph: +61 2 5615675 (BH)
Email: ollis@redbck.enet.dec.com            *  *      +61 2 6268533 (AH)
ICBM: 33 43'S 150 52' 15"E                    +       +61 2 5615488 (FAX)
                                             *
   Terra Australis Espirito Santo - The Great Southland of the Holy Spirit
Newsgroups: sci.electronics