HDTenEightyP/NetNews huggingface dataset:
From: ar961@cleveland.Freenet.Edu (Duane Kaufman)
Newsgroups: sci.electronics
Subject: UART info sought
Date: 26 Jan 93 15:09:40 GMT
Reply-To: ar961@cleveland.Freenet.Edu (Duane Kaufman)
Organization: Case Western Reserve University, Cleveland, OH (USA)
NNTP-Posting-Host: hela.ins.cwru.edu


Hello!

Just for a project I am looking to build a very simple serial to parallel
converter. I was wondering if anyone can point me to a source (catalog etc)
for manufacturers of UART chips?

Thanks in advance!

-- 
                                                     TheSeeker
Duane Kaufman
Internet: dkaufman@vms.macc.wisc.edu
BitNet:   dkaufman@wiscmacc.BitNet        I looked under chairs...
From: agodwin@acorn.co.uk (Adrian Godwin)
Newsgroups: sci.electronics
Subject: Re: Wanted : Nicad Charger Plans
Keywords: cell battery alkaline charging duracell
Date: 26 Jan 93 13:58:30 GMT
Organization: Acorn Computers Ltd, Cambridge, UK

In article <1juf3rINNlbd@rave.larc.nasa.gov> kludge@grissom.larc.nasa.gov (Scott Dorsey) writes:
>I would bet that the charger you saw was for standard carbon-zinc cells.
>The carbon-zinc batteries can be recharged somewhat, but they won't work
>terribly well afterward and you can only get one or two rechargings out
>of them.  Rechargers for these batteries were quite popular back before
>NiCds and alkaline cells came out.

It was claimed to be suitable for zinc-carbon, alkaline or nicad : 
the charge rate was actually chosen to suit nicads, but appeared to
have been designed for a peak current of 120mA. This gave an 
average of around 40mA, and very long charge times (especially
since alkalines are much higher capacity than nicads).
It was claimed that the intermittent charge current was kinder to
nicads too, reducing the formation of shorts between electrodes.

>
>If you charge an alkaline battery, your chances of rupturing it are
>pretty good.  I've never seen one literally explode, but I have seen
>them split down the side and spray causic goo around.  Don't do it.  It's
>not worth it.
>--scott

Quite true : I had several split or leak, though none were very
hazardous - just minor dribbles, and the charger has a cover over it.
Of course, this might not have happened if I'd charged for a week
or two at a lower rate ...

Why do they leak ? Is it thermal expansion, or gas evolution as
with Nicads ?

-adrian

-- 
Adrian Godwin : agodwin@acorn.co.uk : adrian@fangorn.demon.co.uk : g7hwn@gb7khw
ObDisclaimer  : I believe this rubbish .. don't imagine that anyone else does.
Newsgroups: sci.electronics
From: nasiom@hall106.its.rpi.edu (Milton Peter Nasiopoulos)
Subject: components for sale
Reply-To: nasiom@rpi.edu
Organization: Rensselaer Polytechnic Institute, Troy, NY.
Date: Sat, 23 Jan 1993 08:04:01 GMT


Hi all, now that I'm in college I don`t have time to play around with
electronics stuff so I have to sell off the mass amounts of components
I've collected over the last four years.  Please help me, I need space
and money!  If you see anything you need e-mail me at 
nasiom@rpi.edu    thanks!!!    and please, if you can get it cheaper
don't flame me, I'm already selling them for less than what I
originally paid for 'em.

prices are as follows (shipping will be a flat rate of $2.75):

RESISTORS   1/4 watt  1%          100/$1.50

10, 22.1, 33.2, 47, 100, 121, 150, 162, 267, 392, 402, 470, 562, 682,
825, 1.21k, 1.5k, 1.78k, 2.74k, 3.16k, 3.32k, 3.92k, 5.62k, 6.82k, 8.25k,
10k, 15k, 22.1k, 24.9k, 27.4k, 30.1k, 33.2k, 47k, 56.2k, 82.5k, 100k,
182k, 221k, 267k, 274k, 332k, 392k, 470k, 562k, 1.0m

TRANSISTORS

        2N3903, 2N3904, 2N3906, 2N4401, 2N4402, 2N4403 --- 10/$1

       TIP29C, TIP30C, TIP31C, TIP41C, TIP101 ---- 56 CENTS EA.

VOLTAGE REGULATORS

       7805T, 7905T, 7908T, 7812T, 7815T, 7918T, 7824T, 7924T ---- 55
CENTS EA.

        7806T, 7810T, 78L12, 78L05, 78L08 ---- 35 CENTS EA.

I.C. SOCKETS 8 PIN --- 7.5 CENTS EA.    8 PIN GOLD WIREWRAP --- 59 CENTS

              14 PIN --- 12.5 CENTS      16 PIN GOLD WIREWRAP --- 75 CENTS

              16 PIN --- 12.5 CENTS

DISK CAPACITORS ----- 10$1

        68 pf    220 pf    330 pf   .001 mfd    .0047 mfd        ALL 50 VOLTS

       

        100 pf  1.5KV ----8/$1

RADIAL MONOLYTHIC CAPACITORS       ALL 50 VOLTS

        100pf    .001mfd   .0022mfd  ----- 10/$1

       .0047mfd    .01mfd    .047mfd  ------ 10/$1.25

       330pf ---- 10/$1.50

ELECTROLYTIC CAPACITORS

        2.2 MFD  50V ---- 10/$1

        2.2 MFD  100V --- 10/$1.10

        4.7 MFD  25V ---- 10/$1

        33 MFD  35V ---- 10/$1.25

        220 MFD 35V ---- 8/$1

FUSES    1/2 AMP   3/4 AMP    2.5 AMP    3 AMP    4 AMP ----- 10/$1

MISC.

        RED LEDS ---- 10 CENTS       GREEN OR YELLOW LEDS ----- 12 CENTS

        BNC CHASSIS MT. ---- $1.25

        5 LUG TIEPOINT ---- 7/$1

        3.5" PRESTRIPPED WIREWRIP WIRE ---- 50/$1

        22/44 EDGECARD CONNECTORS ----- 45 CENTS

        .0015 MYLAR CAPACITOR ----  10/$1

        I.C.`S    741 --- 45 cents     555 --- 30 cents      556 --- 55 cents

        1 ohm  5%  5 WATT  RESISTOR ---- 25 CENTS

        1N914 DIODE  ----- 50/$1.25  OR  100/$2
From: cstadbg@csv.warwick.ac.uk (Mr M J Brown)
Newsgroups: sci.electronics
Subject: Re: hard disk orientation
Date: 27 Jan 1993 09:49:58 -0000
Organization: Computing Services, University of Warwick, UK
NNTP-Posting-Host: clover.csv.warwick.ac.uk

In article <C1HGpH.H8r@ms.uky.edu> msunde01@mik.uky.edu writes:
>
>No, it's not, really.  I've checked manufacturer's specs on several models  
>(e.g. Connor, Maxtor, Seagate) and they all say vertical mounting is fine.   
>Just don't mount it upside down (I'm not sure why...)

Which way is "up" on a Conner CP3000 ... circuit board up or down ????

Hope mines right way up

=============================================================================  
     _/      _/   _/   _/  _/   _/_/_/_/   |
    _/_/  _/_/   _/   _/_/     _/          |         Michael Brown
   _/  _/  _/   _/   _/       _/_/         |
  _/      _/   _/   _/_/     _/            |   cstadbg@csv.warwick.ac.uk
 _/      _/   _/   _/  _/   _/_/_/_/  _/   |     mjb@dcs.warwick.ac.uk
                                           |    csulo@csv.warwick.ac.uk
=============================================================================
From: d2bohre@dtek.chalmers.se (Henrik Bohre)
Newsgroups: sci.electronics
Subject: Re: Recording sound on chip
Date: 26 Jan 93 11:12:44 GMT
Organization: Chalmers University of Technology, Gothenburg Sweden

sivaram@hplabsz.hpl.hp.com (S. Sivaramakrishnan) writes:

>I am looking for a cheap method to record and playback about 15 seconds of
>sound on a chip.

>The whole setup, I GUESS, will comprise:
>1) A microphone
>2) An A/D converter that digitizes the sound
>3) A unit that accepts the commands "record" and "playback"
>4) Some memory that holds the sound image
>5) A D/A converter to generate an analog signal
>6) A speaker for playback
>7) Power supply

>Does a chip that has most/all the features except the power supply exist?

>If there is an alternative/better method I would be extremely interested to
>know.

>Sivaram

There's a chip that does almost exactly what you want. The chip contains
microphone amp, ADC, memory, DAC, speaker amp, and control logic. Ofcourse
I don't remember the name exactly, but I think it was something like:
"ISDNxx12" for 12 seconds recording with x bps
"ISDNxx24" for 24 seconds recording with x/2 bps.
The memory was some kind of analogue memory with 128 different states, if I
remember it correctly.

Mail me if you want further imformation about the chip.

Henrik Bohre

  @>-+--
From: rsl09@kuhub.cc.ukans.edu
Newsgroups: sci.electronics
Subject: Re: Power Amplifiers
Date: 25 Jan 93 19:50:59 GMT
Article-I.D.: kuhub.1993Jan25.135100.46744
Organization: University of Kansas Academic Computing Services

In article <15579.2b5e3cf6@ohstpy.mps.ohio-state.edu>, garland@ohstpy.mps.ohio-state.edu writes:
> In article <1jkrndINNrht@usenet.INS.CWRU.Edu>, ah335@cleveland.Freenet.Edu (Richard Banks) writes:
>> In a previous article, schaefer@sal-sun93.usc.edu (Peter Schaefer) says:
>> 
>>>
>>>Could anyone out there please give any recommendations on books or other such
>>>literature regarding large-scale power amplifier design? Thanx in advance.
>>>					Peter Schaefer
>>>
>> 
>> I am looking for books on this subject as well, please follow-up to the
>> group.
>> 
>> Thank you.
> 
> How about defining your needs a bit more precisely? Do you want 1MW high
> frequency rf designs, 10kW rf induction furnance designs, ultrasonic amplifier
> designs for medical uses, 1kW audio amplifiers for rock concerts, UHF
> television 300kW designs? Or are you interested in motor controller amplifiers,
> wideband pulse amplifiers for radar applications? Do you need amplifiers with
> 50ohm input/outputs? Voltage sources? Current sources? Give us some guidance
> and maybe we'll all be able to offer suggestions.
> 
> Jim                                                of


  I am interested in a power amplifier that could drive a DC motor/actuator.
I am using the actuator in a slow-response feedback loop. The power amplifier
should interface an OP-AMP, that produces the error signal, and the
actuator that demands up to 3 Amps for input voltages up to 20 volts.
Therefore, I need a push-pull 60 W DC power amplifier. I have been able
to find couple of power OP-AMPs that seem to to able to do the job. But,
they are expensive - price is around $100. 
Thanks for any suggestion.

Hesany


 
Newsgroups: sci.electronics
From: eric@telebit.com (Eric Smith)
Subject: Re: Sony D5000 "my first Sony" portable CD player
To: wa2ise@cbnewsb.cb.att.com
X-Disclaimer: Everything I write is false.
Organization: Telebit Corporation
Date: Thu, 21 Jan 1993 15:22:31 GMT

>>On Thu, 21 Jan 1993 04:47:21 GMT, wa2ise@cbnewsb.cb.att.com (robert.f.casey) said:
> Anyone ever see this model, was wondering if it's 16 bit (some old
> CD players did only 14bit), any oversampling (doubt it), any other
> features?

I'd be surprised if it wasn't 16 bit 4x oversampling, as that was about the
cheapest stuff in production in 1988.  It might only be 2x oversampling, but
a unit with no oversampling would be expensive to produce.

Now "1 bit" stuff costs less to manufacture than "normal" D/As, but the
marketing folks tout it as a feature so they can get more bucks for it :-(

Cheers,
Eric
Newsgroups: sci.electronics
From: wout@dutentb.et.tudelft.nl (Wout Serdijn)
Subject: Re: Internal output resistance on op amps
Organization: Delft University of Technology, Dept. of Electrical Engineering
Date: Thu, 21 Jan 1993 08:39:43 GMT

In <1jkrvsINNrmu@usenet.INS.CWRU.Edu> ah335@cleveland.Freenet.Edu (Richard Banks) writes:


>What is the average resistance range in ohms of R_out on a op amp.

>Thanks.

In most cases the output resistance of an op amp is formed by the output 
resistance of a (bipolar) transistor in parallel with its biasing circuit.
Depending on the type of op amp (especially its current consumption and
the process parameters) the output resistance therefore can vary between 
10 kilohms and 100 Megohms.

But ....

When the op amp is used in a negative-feedback configuration the output
resistance of the total circuit lowers due to the loop gain in the circuit.

For example:

Suppose you apply an ordinary op amp as a voltage follower, i.e. you connect
the output to the negative input the output resistance can be a few ohms. As
an op amp in most cases is used in a negative-feedback configuration it often
is said that the op amp (itself) has a low output resistance. Now you know why.

Good luck.

Wouter

Newsgroups: sci.electronics
From: strong@tc.fluke.COM (Norm Strong)
Subject: Re: BOOKS NEEDED:  tube primer
Organization: John Fluke Mfg. Co., Inc., Everett, WA
Distribution: usa
Date: Thu, 21 Jan 1993 14:56:46 GMT

In article <C0wnMy.64F@cmcl2.nyu.edu> ali@cns.nyu.edu writes:
}
}i'm looking for a good tube electronics book.  something that has application examples/notes/etc...  also, if possible, a book on specifically guitar tube amps (specs/design/schematics (!!))
}
}i'm not sure the latter would be made available but basic tube electronics should, eh?

I believe that the best one-stop-shopping book on electronic design
using tubes was written just as the end of the tube era.  It is:

The Electronic Designer's Handbook by Landee, Albrecht & Davis.  Your
library should have a copy.  

I learned out of it!  

-- 

Norm Strong  (strong@tc.fluke.com)
2528 31st S.   Seattle WA 98144   USA
Newsgroups: sci.electronics
From: ardai@zax.eda.teradyne.com (Michael Ardai)
Subject: Re: Up/Down Counter w/o clock?
Organization: Teradyne, Inc. Boston MA
Date: Sun, 24 Jan 1993 03:56:22 GMT

In article <1993Jan22.082444.184269@zeus.calpoly.edu> mruddick@joule.elee.calpoly.edu (Michael Ruddick) writes:
-I am trying to locate an up/down counter that does not require a clock to be
-present in order for it to work.

Look at the 74LS193 for hex or the 74LS192 for BCD.
/mike
-- 
\|/     Michael L. Ardai     N1IST             Teradyne ATG Boston
--- -------------------------------------------------------------------------
/|\                    ardai@maven.dnet.teradyne.com
From: scottcr@wkuvx1.bitnet
Newsgroups: sci.electronics
Subject: Re: Power Supply Question
Date: 23 Jan 93 10:09:32 CST
Organization: Western Kentucky University, Bowling Green, KY

In article <C1AH65.KGp@acsu.buffalo.edu>, v064mcqs@ubvmsb.cc.buffalo.edu (NEIL GANDLER) writes:
> 
>     Im designing a small power supply. I would like to know if using a 12v
> center tap transformer when full wave rectified and smoothed be more than
> 15 volts to allow a 12 volt regulator 7812 work properly. From my understanding
> the 78 series regulators need a 3 volt difference atleast. 
> 
> 		Neil Gandler

Yes you do need about that margin for the 7812 to reg properly.  
Depending upon 1) the amount of current you plan to draw, and 2)
the size of your (cap input) filter capacitor (the larger the better),
you may be O.K.  Also, depending upon the source of the Xfmr, just
because it's labeled 12 v does not necessarily mean it will produce
12.0 v rms with no load, often they produce slightly more.  The filter,
under no-load will charge to about 1.4 times the rms value minus the
diode drop, which for a silicon bridge will be about 1.3 v.
With modest loads, you can expect about 1.2 times the rms value and be
safe.  The internal resistance of the secondary can also enter into
it at high current values.

-- 
Chris Scott,  C/E Public Radio,  Western KY Univ,  (502) 745-3834
SCOTTCR@WKUVX1.BITNET      fx off: 745-2084     fx hm: 781-1232
From: claude@bauv.unibw-muenchen.de (Claude Frantz)
Newsgroups: sci.electronics
Subject: CMOS PAL
Date: 27 Jan 93 09:48:02 GMT
Organization: University of the armed forces, Munich
NNTP-Posting-Host: bauv106.bauv.unibw-muenchen.de
Keywords: PAL CMOS

Hello !

Does anybody known about PALs in CMOS technoloy, compatible with the 4000 CMOS family,
i.e. for supply voltage up to 15 V. ? I'm looking for a part like the PAL24L10.

Many thanks in advance

Claude
From: pjh@mccc.edu (P. J. Holsberg)
Newsgroups: sci.electronics
Subject: Datasouth 220 Printer Question
Date: 20 Jan 93 23:10:39 GMT
Organization: The College on the Other Side of U. S. 1

A local company recently gave us a Datasouth 220 printer, and I have it
working after a fashion. The problem is, it's S L  O   WWW!

I'm using the parallel interface and 16 cpi but the 220 cps isn't
obvious. It seems to collect a line of characters very slowly and then
prints the line quickly.

It doesn't seem to matter what FTN 35's value is.

Anyone have any suggestions?

Thanks.
---
Prof. Peter J. Holsberg      Mercer County Community College
Voice: 609-586-4800          Engineering Technology, Computers and Math
FAX: 609-586-6944            1200 Old Trenton Road, Trenton, NJ 08690
Internet: pjh@mccc.edu       Trenton Computer Festival: April 17-18, 1993
Newsgroups: sci.electronics
From: kevin@clsi.COM (Kevin Cameron)
Subject: Re: making 110V into 220v
Originator: kevin@dubhe
Reply-To: kevin@clsi.com
Organization: CAD Language Systems Inc.
Date: Mon, 25 Jan 93 19:23:26 GMT


Try looking for an "auto"* transformer - normally used for dropping the line
voltage without isolation for jobs like battery charging that require a lot of
power. You might be able to find one which can give you a 1:2 step-up.

Kev.

* - short for "auto-wound" meaning the transformer only has one winding that acts
    as both primary and secondary.
--
From: rose@bucknell.edu (philip rose `94)
Newsgroups: sci.electronics
Subject: Scanner modifications
Date: 23 Jan 93 17:15:37 GMT
Organization: Bucknell University, Lewisburg, PA
NNTP-Posting-Host: adhara.cs.bucknell.edu

Does anyone out there know how to modify a (Bearcat) scanner so that it
picks up frequencies that are locked out (like cellular phone freq.)?

-------------------------------------------------------------------------------
Phil Rose
rose@coral.bucknell.edu
Newsgroups: sci.electronics
From: vnelson@ccu.umanitoba.ca (Gerald Vernon Nelson)
Subject: ALD4701 User?
Organization: University of Manitoba, Winnipeg, Canada
Date: Tue, 26 Jan 1993 01:22:49 GMT

I am looking for information from anyone using the 
Advanced Linear Devices 4701 Quad Rail to Rail Opamp.

I am interested in acquiring information on failure rates and modes.

In our application, this component failed in 8% of all units.
1/2 of those failure were due to a misaligned pin which did not
get soldered.  The second failure appears to be a loose wire bond
on the V+ pin of the I.C.

Does anyone have any supporting/conflicting data on use of this chip?

Thanks for any info, 
Vern Nelson
From: gutnik@gallium.berkeley.edu (Vadim Gutnik)
Newsgroups: sci.electronics
Subject: HP measurement equipment manual wanted.
Date: 22 Jan 1993 18:55:16 GMT
Organization: University of California, Berkeley
Distribution: us
NNTP-Posting-Host: gallium.berkeley.edu
Summary: Looking for manual for HP4141A dc source.
Keywords: Hewlett Packard documentation, DC source, measurement equipment

I have a 4141A DC source set up as part of a 4062A wafer prober system.
(If you don't know what I'm talking about at all, hit 'n' now, it ain't
getting any better.) 

I've been trying to communicate with it via HPIB from an HP 350 machine.
I can get it to do some things, but it often hangs when I try to calibrate
the sources.  I tried the commands for the 4142B, the 4145A, ... and other
similar machines, but none of them are apparently quite close enough.  So:

does anybody have one of these they use ? (I won't ask for regularly.  Use ever
will be just fine).  More importantly, do you have the manual for this thing?
I need to know what the bits in the status byte mean as well as the full list
of commands if possible.  Mail gutnik@argon.  Thank you.

		-Vadim
Organization: Queen's University at Kingston
Date: Fri, 22 Jan 1993 18:34:24 EST
From: <LEEK@QUCDN.QueensU.CA>
Newsgroups: sci.electronics
Subject: Re: PAL Software
Distribution: usa

In article <oxenreid.727419603@chaos.cs.umn.edu>, oxenreid@chaos.cs.umn.edu ()
says:
>
>I would like to get some PAL design software for the IBM pc or
>AIX 3.2, if such beasts exist for cheep/free.

There is the OPAL JR available from National Semiconductor FREE. It is
a demo version of their much larger commerical package.  You get a
demo program + utilities to convert  equation <-> JEDEC.

There is PLDSHell+ from Intel FREE.  It is a full blown package that
does equations, truth tables, state machines and simulations.  I haven't
try it with PAL chips.  (It does support their PLD's that are supersets
of common 20 - 24 pins PALs)

As for AIX, best bet is to get PALASM which is written in FORTRAN to
compile under your environment.  I have seen the Commodore Amiga version
with full FORTRAN source around.  Email me if you really want to get that
.

>Thanks
>oxenreid@chaos.cs.umn.edu  __chris__

K. C. Lee  "When you are out of cash, the only thing you can do is work."
Elec. Eng. Grad. Student for hire...
Organization: University of Illinois at Chicago
Date: Wed, 27 Jan 1993 15:45:29 CST
From: Rich Chong <U41602@uicvm.uic.edu>
Newsgroups: sci.electronics
Subject: Re: How do I create a 2A load to test a power supply?
Distribution: sci.electronics
 <1993Jan24.130915.10811@bnr.uk>

>First measure the open circuit voltage at the outputs. You may see a bit more
>than 20 Volts. Don't worry unless it's a lot more (about 30V). This checks
>there is juice coming out. If no voltage - it's toasted, but make sure you
Sometimes not toast. Some power supplies wont come up if there isn't any
load sensed, such as in an open circuit.

>I wouldn't recommend trying to measure the current with your meter alone, as
>this basically shorts the power supply, and the current may burn out the
>secondary winding on the transformer (or your meter!). Instead, get a 20 Ohm
Usually trashes the meter (hopefully, it's fused protected in that range).

>resistor rated for 20 Watts (This will get 1 Amp out of your supply) or a 10
>Ohm resistor rated at 40 Watts to get 2 Amps out of the supply. Remember, you
Also remember that 40W of heat makes for one very very hot resistor!
                                                                    rich chong
From: thomasd@tps.COM (Thomas W. Day)
Newsgroups: sci.electronics
Subject: Re: Recommendations for Digital Multimeter
Date: 27 Jan 93 17:47:07 GMT
Distribution: usa
Organization: Telectronics Pacing Systems

In article <15657.2b645387@ohstpy.mps.ohio-state.edu> garland@ohstpy.mps.ohio-state.edu writes:
>In article <C1FqqK.2vt@taligent.com>, kayshav_dattatri@taligent.com (
Kayshav Dattatri) writes:>> I want to buy a digital multimeter for my hobby 
set. I have seen models>> from Philips, Funa etc. I'm willing to spend 
about $100.>> 
>> Can the gurus recommend a good model and source to get it cheap (mail order or
>> in the SFO bay area market).
>I recommend the Beckman series of DMM's. There are several in the $100 price
>range. I've found them to be very rugged, and they have large LCD displays with
>good contrast -- better than the Fluke line in that regard.  Also, a point
>frequently overlooked, is that they have extremely long battery life -- about
>x10 longer than the Fluke's, and they're also well-shielded against rf.

I've used both, Beckman and Fluke.  I like both, but personally own a Fluke 
8060A for the features.  The battery life on my Fluke has been satisfactory, 
more than a year per 9V.  I can't complain about the LCD contrast.  I use it 
in audio applications, often where the ambient light is marginal, and it is 
always readable.  Fluke's customer service is amazing.  My 8060A was damaged 
in shipping two years ago.  Really battered.  Fluke repaired it and got it 
back to me in 3 days.  And the cost of repair was extremely reasonable.
Newsgroups: sci.electronics