Am looking for a 4-20 ma…calibration device. I know there are many new
units available, but am looking to buy a used unit..

Please let me know desired price, info about unit, and location

Thank You

Fredr…@usa.pipeline.com

In article <4sbl6n$…@info.forthnet.gr> t…@onned.gr (Nikos Bovos) writes:
>   Althought I’m not new in newsgroups , this is my first message/mail…
>   I’m having trouble with a device that i’m developing and i want some
>   help…Here is the problem :
>   I want to slowly turn on (let’s say 10 seconds) and then slowly turn
>   off (let’s say again 10 seconds) some bulbs (suppose 1 KW all , or
>   less), or first slowly turn on , then keep them on for 5 seconds and
>   then slowly turn off  and so on…
>   All my tries did not worked … Any suggestions ?

What kind of bulbs?
What have you tried?
Is using a microcontroller, PIC, etc. a possibility?
What kind of flexibility to change the programming do you want?
To what extent is cost a constraint?

Etc. You can never provide too much info.

Post to this group – which is as good a place as any.

— sam

Silicon Graphics has a new open position in its Mountain View
headquarters for a Power Supply Support Engineer. This engineer will
provide technical support to multiple power supply engineers for product
development projects and manufacturing released products.
Responsibilities include performing engineering test and evaluation on
vendor prototype power supplies, doing product audits and system
evaluations, and making recommendations for design changes to correct
technical deficiencies.

This position requires an MS/BSEE or equivalent, plus 3 or more years
experience in testing and evaluation of power supplies and related
hardware. Strong written and verbal communication skills are required.

To apply for this position, email resume to sras…@sgi.com, fax to
415-933-4392, or call Susan Raskin at 415-933-4523. Silicon Graphics is
an equal opportunity employer. Principals only, please.

–
Susan Raskin                            direct dial: 415-933-4523
ASD/ISD Staffing                        fax:         415-933-4392
Silicon Graphics, Inc.                  email: sras…@sgi.com
2011 North Shoreline Boulevard          web:  http://www.sgi.com
MS 7U-553
Mountain View, CA  94043-1389

If you can supply any of the above items in bulk, please contact
Elusion.

Thanks,

–
ELUSION
http://www.elusion.co.uk

Presenting You To The World
—

Theo Bessem’s Shoulder To Shoulder
http://www.elusion.co.uk/theo_bessem

I am looking for surface mount soldering equipment, something like a PACE
rework station, but would be interested in other stuff, too.  

I am interested in purchasing old math, scientific, and engineering
devices.  What I am looking for are devices such as old mechanical
calculators (electric motor powered or non-electrical), high quality
engineering slide rules (not plastic), planimeters (mechanical integrating
devices), mechanical cipher machines (encryption/decryption), and other
devices such as these.  I also have an interest in sextants and old
surveying equipment.

I am not interested in adding machines that print on paper tape or
electronic calculators.  I only want mechanical devices.

If you have anything like this that you are interested in selling, please
send me a private e-mail message.

Phil Sherrod (Phillip.Sher…@nashville.com)

 –  usenet.sci.electronics.equipment  07/15/1996  –

If you are interested in buying or selling quality used general purpose
test & measurement equipment, please call Metric at (800) 432-3424, or
fax the list of equipment you are intereted in selling at (415) 341-8874
for a prompt offer to Charles Nelson.

If you would like to receive a free catalog, please e-mail us your snail
or you can visit our home page at http://www.metricsales.com under
"products" and your can view our equipment either by mfg. or by type of
equipment.  

You can also check out our On-going auction and bargain basement
items under "products" for great deals on test instruments available only
through our web page.

I have the following equipment for sale. Unless otherwise noted, all
equipment is functional, calibrated, and cosmetically excellent. Prices do
not include shipping.

HP10326A Time Interval Standard. Dual channel time interval reference with
outputs of 5, 10, 20, 50, or 100 nanoseconds with less than 5 picoseconds
of jitter. $60.

HP1630G Logic Analyzer. 65 channel analyzer with 25 MHz state and 100 MHz
timing with glitch capture. All pods included. Interactive CRT display
with X-Y charting, time interval measurements and histograms, cursor
measurements, and time positional and intermodule linkage measurements.
Pattern triggering with qualifiers and delaying. HP-IB and HP-IL
interfaces for printer output, disc and tape storage, and for computer
control of instrument. Time/date stamping of measurements and non-volatile
disassembler memory. $550.

HP1725A 275 MHz Oscilloscope. Portable scope with dual channel 10 mV/div
to 5 V/div vertical sensitivity, 10 ns/div to 0.5 s/div horizontal with a
delayed sweep of 10 ns/div to 20 ms/div. Calibrated delay time with "delta
time" mode and rear panel DVM output for accurate time interval
measurements. Fully functional except that delayed sweep is inoperative on
0.5 ms/div, 5 us/div, 50 ns/div, 20 ns/div, and 10 ns/div ranges. (The
delayed timebase is fine on all other settings and the main timebase works
perfectly on all settings.) I don’t have the time to troubleshoot it, so I’ll
sell it cheap! $150.

HP1727A 275 MHz Storage Oscilloscope. Portable scope with dual channel 10
mV/div to 5 V/div vertical sensitivity, 10 ns/div to 0.5 s/div horizontal
with a delayed sweep of 10 ns/div to 20 ms/div. Calibrated delay time with
"delta time" mode and rear panel DVM output for accurate time interval
measurements. Auto-store, variable persistence, and auto-erase. Storage
writing speed is 2,775 div/microsecond. Some minor scratches on the front
panel. $300.

HP182C/1815B/1817A/1106B/1105A 12.4 GHz sampling scope/TDR system. Large
screen portable scope with TDR/sampler plug-in and sampling head.
Bandwidth is 12.4 GHz with 28 picosecond risetime. 2 mV/div to 0.5 V/div
vertical sensitivity. TDR range of 1 cm/div to 1000 meters/div.
Dielectric calibration for air, polyethylene, or variable. TDR resolves
discontinuities to 0.5 cm. All cables and manuals included. $500.

HP3580A Spectrum Analyzer. Portable instrument with 5 Hz to 50 kHz range,
1 Hz to 300 Hz resolution bandwidth, and 0 Hz to 50 kHz span. Log and
linear sweeps. Input sensitivity from 0.1 microvolt rms to 20 volt rms
full scale. Vertical scaling can be set to linear (volts), or logarithmic
(10 dB/div or 1 dB/div). Digital trace storage, adaptive sweep. Tracking
oscillator, local oscillator, and plotter outputs. Set up to run from
and recharge internal nicad battery pack (nicads not supplied). $700.

HP37203A HP-IB Extenders (2 each). Used to extend HP-IB (IEEE-488)
interface via coaxial cable up to 1000 meters. Has error detection and
correction. Supports all HP-IB functions including pass control and
parallel poll. $40 for one, $70 for the pair.

Heath ID-4804 Byte Probe. Handheld device with 8 TTL-level input channels
that can be set to trigger an external device when a specified pattern
occurs. As a standalone device, it will show activity on each of the 8
channels via LED indicators, and illuminate another LED (with optional
latching) when a coincidence with the specified pattern occurs. Manual
included. $20.

Heath IT-2250 Autoranging Digital Capacitance Meter. Handheld device with
full scale ranges in decade steps from 199.9 picofarads to 199.9
millifarads. 0.2% accuracy on 199.9 pF to 199.9 nF ranges and 5% accuracy
on 1.999 uF to 199.9 mF ranges. 2 volt maximum test voltage. Manual
included. $40.

Regards,
Stan

–
———————————-
|  Stan Perkins   |  ASMG, Inc.  |
| s…@netcom.com | 619-490-9074 |
———————————-

***********************************************************
                                                          *
    MEMBER NAME: LUNCHBOX                                 *
                                                          *
***********************************************************

  <%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>
  <%>                                                                     <%>
  <%>                             Making the                              <%>
  <%>                                                                     <%>
  <%>                              Lunch Box                              <%>
  <%>                              ===== ===                              <%>
  <%>                                                                     <%>
  <%>              Written, Typed and Created by: Dr. D-Code              <%>
  <%>                                                                     <%>
  <%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>[%>

  Introduction
  ============

  The Lunch Box is a VERY simple transmitter which can be handy for all sorts of
  things. It is quite small and can easily be put in a number of places. I have
  successfully used it for tapping fones, getting inside info, blackmail and
  other such things. The possibilities are endless. I will also include the
  plans for an equally small receiver for your newly made toy. Use it for just
  about anything. You can also make the transmitter and receiver together in
  one box and use it as a walkie talkie.

  Materials you will need
  =======================

  (1) 9 volt battery with battery clip
  (1) 25-mfd, 15 volt electrolytic capacitor
  (2) .0047 mfd capacitors
  (1) .022 mfd capacitor
  (1) 51 pf capacitor
  (1) 365 pf variable capacitor
  (1) Transistor antenna coil
  (1) 2N366 transistor
  (1) 2N464 transistor
  (1) 100k resistor
  (1) 5.6k resistor
  (1) 10k resistor
  (1) 2meg potentiometer with SPST switch
  Some good wire, solder, soldering iron, board to put it on, box (optional)

  Schematic for The Lunch Box
  ===========================

  This may get a tad confusing but just print it out and pay attention.

           [!]
            !
          51 pf
            !
         —+—-  ————base   collector
        !        )(               2N366       +—-+——/\/\/—-GND
      365 pf     ()              emitter           !
        !        )(                 !              !
        +——–  —+—-         !              !
        !             !    !        !              !
       GND            /  .022mfd    !              !
                   10k\    !        !              !
                      /   GND       +————————emitter
                      !             !              !             2N464
                      /           .0047            !          base   collector
                2meg  \—-+        !              !   +——–+       !
                      /    !       GND             !   !                !
                          GND                      !   !                !
          +————-+.0047+——————–+   !                !
                                                       !   +–25mfd—–+
              —————————————–+   !            !
         microphone                                        +–/\/\/—–+
              ———————————————+   100k     !
                                                                        !
                    GND—->/<———————!+!+!+—————+
                          switch                  Battery
                      from 2meg pot.

  Notes about the schematic
  =========================

  1.  GND means ground
  2.  The GND near the switch and the GND by the 2meg potentiometer should be
      connected.
  3.  Where you see:  )(
                      ()
                      )( it is the transistor antenna coil with 15 turns of
                         regular hook-up wire around it.
  4.  The middle of the loop on the left side (the left of "()") you should run
      a wire down to the "+" which has nothing attached to it. There is a .0047
      capacitor on the correct piece of wire.
  5.  For the microphone use a magnetic earphone (1k to 2k).
  6.  Where you see "[!]" is the antenna. Use about 8 feet of wire to broadcast
      approx 300ft. Part 15 of the FCC rules and regulation says you can’t
      broadcast over 300 feet without a license. (Hahaha). Use more wire for an
      antenna for longer distances. (Attach it to the black wire on the fone
      line for about a 250 foot antenna!)

  Operation of the Lunch Box
  ==========================

  This transmitter will send the signals over the AM radio band. You use the
  variable capacitor to adjust what freq. you want to use. Find a good unused
  freq. down at the lower end of the scale and you’re set. Use the 2 meg pot. to
  adjust gain. Just fuck with it until you get what sounds good. The switch on
  the 2meg is for turning the Lunch Box on and off. When everything is adjusted,
  turn on an AM radio adjust it to where you think the signal is. Have a friend
  say some shit thru the Box and tune in to it. That’s all there is to it. The
  plans for a simple receiver are shown below:

  The Lunch Box receiver
  ======================

  (1) 9 volt battery with battery clip
  (1) 365 pf variable capacitor
  (1) 51 pf capacitor
  (1) 1N38B diode
  (1) Transistor antenna coil
  (1) 2N366 transistor
  (1) SPST toggle switch
  (1) 1k to 2k magnetic earphone

  Schematic for receiver
  ======================

           [!]
            !
          51 pf
            !
       +—-+—-+
       !         !
       )       365 pf
       (—-+    !
       )    !    !
       +———+—GND
            !
            +—*>!—-base  collector—–
               diode      2N366           earphone
                          emitter    +—–
                            !        !
                           GND       !
                                     -
                                     +
                                     - battery
                                     +
             GND——>/<————+
                    switch

  Closing statement
  =================

  This two devices can be built for under a total of $10.00. Not too bad. Using
  these devices in illegal ways is your option. If you get caught, I accept NO
  responsibility for your actions. This can be a lot of fun if used correctly.
  Hook it up to the red wire (I think) on the fone line and it will send the
  conversation over the air waves. If you have any problems or are confused,
  leave me mail on:Hi-Times=702/832/7469  Warez House=702/827/9273

  ______________________________________________________________________________

   Sysops of other systems may use the file as long as none of it is altered.
  ______________________________________________________________________________
   This has been a High Mountain Hackers Production- (c) 1985 by HMH Industries
  ______________________________________________________________________________

Please ignore the last post about the transmitter question, the margins were
off.