Ham Radio/Ham Radio CD-ROM (Emerald Software) (1995).ISO/news/ih91310a/ih91311.txt

Internet Message Format | 1991-04-22 | 27.3 KB

From wang!elf.wang.com!ucsd.edu!info-hams-relay Mon Apr 22 20:57:12 1991 remote from tosspot
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Message-Id: <[e-mail]>
Date: Mon, 22 Apr 91 11:16:11 PDT
From: Info-Hams Mailing List and Newsgroup <[e-mail]>
Reply-To: [e-mail]
Subject: Info-Hams Digest V91 #311
To: [e-mail]


Info-Hams Digest            Mon, 22 Apr 91       Volume 91 : Issue 311

Today's Topics:
                          2m amp info WANTED
                       Deerfield hamfest dates?
                             F connectors
                       Graduate School Inquiry
                           High(?) Speed CW
                           NCARC Superfest
                           New to Newsgroup
                         No-code catching on
                                RACES
                         RACES Bulletin # 166
                       Range of cordless phones
          Re: Antenna Matching Gedanken Experiment (2 msgs)
                 RF exposure - how much is too much?
                        RF exposure question.

Send Replies or notes for publication to: <[e-mail]>
Send subscription requests to: <[e-mail]>
Problems you can't solve otherwise to [e-mail].

Archives of past issues of the Info-Hams Digest are available
(by FTP only) from UCSD.Edu in directory "mailarchives/info-hams".

We trust that readers are intelligent enough to realize that all text
herein consists of personal comments and does not represent the official
policies or positions of any party.  Your mileage may vary.  So there.
----------------------------------------------------------------------

Date: 22 Apr 91 15:13:23 GMT
From: [e-mail]
Subject: 2m amp info WANTED
To: [e-mail]

I am looking for a used 2m FM amp, for a friend.  I am not familiar with 2m
amps and need some advice on how much to spend and what type to buy.  The unit
does not have to have a preamp and SSB capability would be OK.

Any information or offers would be helpful.  The unit must be in good working
order, with manual.

John H. Anderson N5OPY
[e-mail]

------------------------------

Date: 22 Apr 91 17:29:56 GMT
From: brunix!doorknob![e-mail]
Subject: Deerfield hamfest dates?
To: [e-mail]

Can anyone tell me when the Deerfield NH hamfest is this year?  I've
heard conflicting reports of first weekend in May and first weekend in
June.

Thanks,
Paul KA1YNE

--

=============================================================

Paul G. Howard                        email: [e-mail]
Department of Computer Science           phone: [phone]
Brown University                         FAX:   [phone]
Providence RI 02912-1910                 ham:   KA1YNE

------------------------------

Date: 22 Apr 91 14:23:08 GMT
From: sdd.hp.com!wuarchive!rex!ukma!s.ms.uky.edu![e-mail]
Subject: F connectors
To: [e-mail]

[e-mail] (Paul Koning) writes:


[Stuff Deleted]

>Apart from that, they are a mechanical disaster.  I hate UHF connectors, but
>they are wonders of engineering compared to F.  As far as I can see, the
>only reason F connectors exist is because they are far cheaper than
>anything else.

F Connectors do have two advantages over UHF, however.  F Connectors are
rated for outside use (meaning they are considered weatherproof).  F
Connectors also have a specific impedance; UHF connectors do not.

Overall, I agree with the other comments.  I don't prefer to use them.

[Other stuff deleted]

---------------
Harold G. Peach, Jr.                          Internet:  [e-mail]
252 Ag. Engineering Bldg., U.Ky.       Packet Radio:  [e-mail]
Lexington, KY  40546-0276                            Phone:  [phone]

------------------------------

Date: 22 Apr 91 17:01:54 GMT
From: ENUXHA.EAS.ASU.EDU![e-mail]
Subject: Graduate School Inquiry
To: [e-mail]

This question is to any EE faculty in the audience.

Having just completed my BSEE here, would really like to write a master's thesis
in the area of television standards conversion, transmission, or propogation
(analog and digital standards).  Inquiries to faculty here and many other
institutions have found only European and Asian schools pursuing this.  Here
in North America, there seem to be no schools engaged in this- only a handful
of companies and think tanks.

If there are any schools anyone knows of in North America for this, please
notify me ASAP.  MIT and Stanford seem relished in raster graphics research,
but no television directly from what I've been able to find out.

Comments appreciated.
-------------------------------------------------------------------------------
Brian Crawford               INTERNET (current):   [e-mail]
PO Box 804                            (permanent): [e-mail]
Tempe, Arizona  85280        FidoNet:              1:114/15.12
USA                          Amateur:              KL7JDQ
-------------------------------------------------------------------------------

------------------------------

Date: 22 Apr 91 04:41:50 GMT
From: pacbell.com!att!linac!uwm.edu!zaphod.mps.ohio-state.edu!swrinde!elroy.jpl.nasa.gov!turnkey!qed![e-mail]
Subject: High(?) Speed CW
To: [e-mail]

[e-mail] (Ron Miller) writes:

> Re: High speed CW
>
> Why write it?
>
> Put your pencil down, relax, and listen to the QSO. Practice that.
> You don't write down SSB conversations, do you?
>
> I'm pretty solid on 30 WPM from W1AW and working on 35. No writing. No
> reason to.
>
Besides, weren't computers invented for just this purpose (fulfilling
simple, mindless tasks)?

----------------------------------------------------------------------------
Tim Capps     | [e-mail]           | Always, wait, never... no, always
QED Software  | The QED BBS [phone] | keep a litter bag in your car...
----------------------------------------------------------------------------

------------------------------

Date: 20 Apr 91 18:04:41 GMT
From: hpfcso!hpfcdc![e-mail]
Subject: NCARC Superfest
To: [e-mail]

              Northern Colorado Amateur Radio Club

                    presents


                   * SUPERFEST XIII *

               HAMFEST AND COMPUTER FAIR


        Prizes         Saturday, June 8, 1991      Prizes
        Prizes          Doors open 8:00 A.M.      Prizes
        Prizes                      Prizes
                Admission $3.00

               Larimer County Fairgrounds
                   Loveland, Colorado  (*)

            Commercial exhibits and dealers


            VE Exams        Wheelchair accessible

            Plenty of space    ARRL Forum


    Setup available Friday night for commercial exhibitors
    Overnight security provided
    Doors open 6 a.m. Saturday for table setup
    Talkins on 145.115(-) and 146.520
    $7.00 per table (includes one admission)
    RV hookups available -- $7.00/day

    For more information contact Kent Douglass, KA0TTY
                        [phone] (residence)
                        [phone] (office)
                        [e-mail]

    For table reservations contact Orlin Jenkins, K0OJ
                        [phone]

    VE Exam info and registration contact Rick Hubbard, WA0DDC
                        [phone]


(*) 45 miles north of Denver; I25 exit 255 to Col 402 west.

------------------------------

Date: 22 Apr 91 17:46:13 GMT
From: [e-mail]
Subject: New to Newsgroup
To: [e-mail]

X-Queued-By: westinghouse Dialcom $Revision: 2.0 $
X-CMR-Spool-Date: Mon, 22 Apr 91 10:44:44 PDT
     To:  INTERMAIL   (WYY005)
   From:  HANNA.J.R  (WTX1464) Delivered:  Mon  22-Apr-91  7:48 EDT Sys 1038  (21)
Subject:  WEMS/INTERMAIL MESSAGE
Mail Id:  IPM-1038-910422-070270978


I am new to the newsgroup here, but am also a new internet user. I had
a heck of a time getting "signed up" into info-hams, and I would also
like to get on to Packet-radio, hence a couple questions.

Does anyone have the newest info on how to sign up for the newsgroups?

I am also interested in shortwave listening, and being a Packet BBS
SYSOP, I am interested in most ham radio subjects. Anyone care to give
me advice as to any other groups I might be interested in, and how to
join them ?

Thanks for the help !!

Dick   Packet: K3VYY@K3VYY.#SEKY.KY
       Internet: [e-mail]

.end

------------------------------

Date: 22 Apr 91 15:25:04 GMT
From: sdd.hp.com!caen!kuhub.cc.ukans.edu![e-mail]
Subject: No-code catching on
To: [e-mail]

It appears that the no-code Technician class is catching on in Kansas
City, at least.  I went to a testing session on Saturday (4/20) where
there were about 30 people being tested--about 20 of them were taking
the Technician test (me included) and of those 20, 18 were going for
the no-code Tech. The two exceptions were a teenager, upgrading from
Novice, and me (I was the only one who took the 5 wpm test).  There
was only one other person in the whole group who took a code test--he
was upgrading to General.

There was a little good-natured joking from a few "upper-classmen"
about the "Tech Lite" class, but in general, the no-code Tech
applicants were warmly welcomed into the amateur radio community.

I checked out a Technician class study guide from the local public
library, but my primary study tools were the HyperCard ham stacks for
the Macintosh from Diana Syriac (thanks, Diana).  For code practice, I
listened to CW QSO's in the Novice/Tech bands on my Sangean 803A
shortwave receiver, and also the W1AW slow-code sessions on various
frequencies.  The tests (written and code) were easier than I had
anticipated, particularly the code test.

Thanks to all of you who have been answering my questions over the
last few months.  Now I'm eagerly awaiting mail from the FCC :-)

+===========================================+============================+
| Doug Heacock, Academic Computing Services | [e-mail] |
| The University of Kansas, Lawrence, KS    | [e-mail]     |
+===========================================+============================+

------------------------------

Date: 22 Apr 91 15:25:28 GMT
From: swrinde!zaphod.mps.ohio-state.edu!caen!ox.com!emory!ducvax.auburn.edu!eng.auburn.edu![e-mail]
Subject: RACES
To: [e-mail]

Could somebody send me some information on RACES such as what speicifcally they
do (I know generally, but not specifics), how you get involved, etc.  E-mail
is fine.  Thanks in advance.

Brian Hartsfield
[e-mail]

------------------------------

Date: 22 Apr 91 14:24:51 GMT
From: [e-mail]
Subject: RACES Bulletin # 166
To: [e-mail]



------------------------------

Date: 22 Apr 91 13:05:14 GMT
From: swrinde!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!att!cbnewse![e-mail]
Subject: Range of cordless phones
To: [e-mail]

In article <[e-mail]>,
[e-mail] (Damned Yankee) writes:

> ... Has anyone else ever tried to DX (hi hi) cordless phones.
> I'm interested in knowing how far you have been able to DX this low
> power service.


Here is a reprint of an article I published
in the October 1986 issue of "The Radio Enthusiast."


                       NEW CORDLESS PHONE
                         DX RECORD SET?

                      by Bob Parnass, AJ9S

  If you use a cordless telephone, you  may  be  overheard  by
  people 1000 miles away.  So says Jack Albert, a radio hobby-
  ist in New Lenox, Illinois.

  Albert was watching TV channel 2 the  evening  of  June  23,
  1985  when  he  noticed another TV signal competing with the
  local Chicago  station.   Suspecting  a  "band  opening",  a
  natural  phenomenon  in  which  radio signals "skip" off the
  ionosphere, permitting reception of signals from  extraordi-
  nary  distances,  Albert  turned  on  his  6 meter ham radio
  receiver and found that conditions favored reception of sig-
  nals from North Carolina.

  Retuning his receiver to frequencies  adjacent  to  the  ham
  band,  Albert's attention was drawn to two people conversing
  amidst the clamor of several other cordless phone  conversa-
  tions.   Certain  that  the  parties were in North Carolina,
  Albert stated that both parties had "North Carolina accents"
  and  that the slow fading pattern on the cordless phone sig-
  nals matched that on the ham signals from the same state.

  Albert regularly uses his 25 year  old  "Clegg  Interceptor"
  receiver, connected to a 5 element beam antenna on a 45 foot
  tower, to  monitor  radio  signals  from  his  home  station
  WA9FVP.

  Radio hobbyists report  that  reception  of  cordless  phone
  conversations  from distances of one to two miles is common,
  but this may set the distance record in reception  of  these
  signals.
--
============================================================================
Bob Parnass, AJ9S - AT&T Bell Laboratories - att!ihlpy!parnass [phone]

------------------------------

Date: 18 Apr 91 09:16:34 GMT
From: hpda!hpcuhb!hpsqf!hpqmola!hpqmolb![e-mail]
Subject: Re: Antenna Matching Gedanken Experiment
To: [e-mail]

iury43o98iuowoprjufm#


































dstock
















------------------------------

Date: 18 Apr 91 10:33:56 GMT
From: hpda!hpcuhb!hpsqf!hpqmola!hpqmolb![e-mail]
Subject: Re: Antenna Matching Gedanken Experiment
To: [e-mail]

   Sorry about that last garbage, I'm comfortable with transmission lines,
but not with this editor....

   I've always found it easier to put transmission line problems in terms
of a very short pulsed transmission and a  long line.

  A transmitter usually has an output Z which is NOT matched to the line
Let's think in terms of 50 Ohm systems as most people find this easiest.



  Our transmitter is keyed for a period shorter than the time taken to
traverse the line. The transmitter cannot see any effects due to the load
at the end of the line as there has not been sufficient time for any signal
to make the round trip before the Tx unkeys. For this period of time, the
signals on the line are purely a function of the line itself and of the
drive from the transmitter. The line presented the Tx with a Z of 50 Ohms,
resistive. The power flow into the line was identical to what our Tx would
put into a 50 ohm resistor connected directly across the Tx output. This is
real power, it (plus transmitter efficiency losses) was measured on our
electricity meter. There is a pair of moving waves going down the line, one
current wave and one voltage wave. they are in phase (ie. + peaks coincide
in time and position) There is a defined ratio of their amplitudes of 50 volts
per amp.
  This pair of waves are presented to the load. if the load is matched, ie
50 ohms resistive, then they are an ideal fit, the maximum power transfer
theorem allows all available power to pass into the load and out of our ken.
If the load is a mismatch, the apparant true 50 Ohm source presented by the
line will not couple all the available power into the load. the actual
power taken may be calculated easily. The real fun comes when we consider
the discrepancy between the available power and the power taken. It is
easy to see that it does not pass into the load. the only alternative is
to travel back up the line to the transmitter. The reflected waves will not
be in phase if the load had a reactive component. When these waves (voltage
and current) reach the Tx, the output Z of the Tx will look like another
load (usually mis-matched). some of the signal passes into the Tx where it
is dissipated, the rest returns down the line. Te voltage and current
components phase having been further influenced by the Tx's output Z.
This signal again reaches the load. Some is passed on, some is reflected
back to the Tx once more. We have a hall of mirrors !

  A continuous transmission can be considered as the superposition of a
continuous series of abutting, phase-coherent pulses. After a time, the
components travelling the line will be like a formula-1 race with some
cars on their n-th, (n+1)th, (n+2)th laps all on the circuit simultaneously
(all at the same speed, though :-))  The multiple signals in both directions
will have phase shifts due to their experiences, Load and Tx impedences, the
time taken to traverse the lina and the number of "laps" each has done.
This is an infinite series,but is soluble. tha trivial case is of total
power into a matched load. Another simple case is of total reflection from
a short or open (180 degree phase difference) load.

The mis matched cases, do not cause the Tx output power to dissipate in the
TX as the voltages and currents presented to the Tx will displace some of
the drive from the Tx. What usually damages a transmitter is that although
the power flow is mild, high voltage/low current and high current/low voltage
conditions can occur depending on the phase shifts involved. Our pricy
final transistors die of over voltage or over current, not over power.

   Real power is taken from the mains, does flow down the line to a mis-
matched antenna. the reflections then cause a reduction of power consumption.
we cannot ignore the velocity of light or the conservation of energy.

  Total reflection gives us a classical transmission line resonator. It takes
real time and energy to build up oscillations,maintening them means just
making up for losses. The effctive Q gives us magnification of voltage and
current, so for low output power we can have destructive voltages/currents.

Apologies for length, I'm not able to phrase it better.
GM4ZNX

------------------------------

Date: 22 Apr 91 15:47:39 GMT
From: usc!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!bronze!bronze.ucs.indiana.edu![e-mail]
Subject: RF exposure - how much is too much?
To: [e-mail]

With all the recent talk about RF exposure, does anyone have a feel for
how much RF is too much for long term exposure at 525 MHz? What I have
been working on is consulting for a family that lives under a channel 23
T.V. station. Measured signal strength is +50 to +60 dBmv (+60 is 1 volt)
in and around the house and property. This was measured using a folded
dipole cut to frequency, on a Wavetek SAM I meter.

Thanks.
--

  John Stigall - Indiana University Computing Services Network  | Waiting for
   750 N. State Rd. 46 Bypass, Bloomington, Indiana 47405       | Amateur Radio
     [phone]            [e-mail]           | Callsign...

------------------------------

Date: 22 Apr 91 17:53:09 GMT
From: sdd.hp.com!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!bronze!bronze.ucs.indiana.edu![e-mail]
Subject: RF exposure question.
To: [e-mail]

With all the recent talk about RF exposure, does anyone have a feel for
how much RF is too much for long term exposure at 525 MHz? What I have
been working on is consulting for a family that lives under a channel 23
T.V. station. Measured signal strength is +50 to +60 dBmv (+60 is 1 volt)
in and around the house and property. This was measured using a folded
dipole cut to frequency, on a Wavetek SAM I meter.

Thanks.

--

  John Stigall - Indiana University Computing Services Network  | Waiting for
   750 N. State Rd. 46 Bypass, Bloomington, Indiana 47405       | Amateur Radio
     [phone]            [e-mail]           | Callsign...

------------------------------

Date: 22 Apr 91 15:36:22 GMT
From: swrinde!cs.utexas.edu!csc.ti.com!ti-csl!tilde.csc.ti.com!axis!sqa.dsg.ti.com![e-mail]
To: [e-mail]

References <[e-mail]>, <[e-mail]>, <[e-mail]>
Subject : Re: No-Code Testing - Who is to adm.

In article <[e-mail]> [e-mail] (Patrick St. Joseph Teahan Taber) writes:
>
>It's true that it says that in the  rules, but neither of the National
>VECs accept VEs unless they are Extra class.  I don't know about the
>smaller VECs, but I've heard that nobody accredits Advanced or General
>VEs.  There's no shortage of examiners and the headaches of mixed-class
>VEs aren't worth it.
>                                     Patrick St. Joseph Teahan Taber, KC1TD

Just goes to show you can't trust everything you hear :-) i.e. Facts
are SO much nicer than rumor!
a)My wife, KI5EV, is an Advanced class VE
b)she is accredited with both W5YI and ARRL (and no-one "smaller")
c)the local clubs here do not consider this a "headache"
d)there have been times when a session was cancelled due to lack
  of availability of a VE - this shortage is one reason why Dawn
  went to the trouble of registering AND giving extra time and
  trouble to study and KNOW the rules and regulations
e)the local test coordinators certainly believe it was "worth it"

It is true that currently generals cannot become accredited VEs.
They can (and do) adminster Novice tests (but cannot issue a CSCE
for partial completion of the requirements).

Patrick, no flame intended, but where did you get your information
that neither National VEC accredits Advanced Class VEs? W5YI distributes
the requirements as spelled out in the FCC Rules and Regulations and
certainly ABIDES by them. The same goes for the ARRL (see the May issue
of QST for a nicely done spread encouraging more folks to become VEs -
notice the two blocks to check: Advanced or Extra). Neither of these
groups would be worthy of being VECs if they acknowledged the rules and
then went on to do what they wanted to instead!
--
Ed Humphries                Texas Instruments, Inc. 512-250-6894
N5RCK                       Internet [e-mail]
-. ..... .-. -.-. -.-       Packet N5RCK@NA4M

------------------------------

Date: 22 Apr 91 14:22:47 GMT
From: usc!cs.utexas.edu!csc.ti.com!ti-csl!tilde.csc.ti.com!axis!sqa.dsg.ti.com![e-mail]
To: [e-mail]

References <[e-mail]>, <[e-mail]>, <[e-mail]>
Subject : Re: No-Code Testing - Who is to adm.

In article <[e-mail]> [e-mail] (Dugal James P.) writes:
>Actually, an Advanced Class ham can be a VE, so as to administer the
>novice and tech exams.

Add: and general and advanced (but not extra) class exams - Extra Class
     VE's (team of 3 of course :-) test prospective Extras (or down)

Note: I ain't one, my spouse KI5EV am one; I just read everything
      and dream of doing 20 wpm! :-)
--
Ed Humphries                Texas Instruments, Inc. 512-250-6894
N5RCK                       Internet [e-mail]
-. ..... .-. -.-. -.-       Packet N5RCK@NA4M

------------------------------

Date: 22 Apr 91 17:05:44 GMT
From: ogicse!orstcs!jacobs.CS.ORST.EDU![e-mail]
To: [e-mail]

References <[e-mail]>, <[e-mail]>, <[e-mail]>
Subject : Re: Adjust frequency of 4 terminal, rectanglular oscillators.

>Nope, he's probably using a crystal oscillator as you said (or one with a
>ceramic resonator).  What he should be using is a voltage-controlled
>oscillator in a 4-pin can, like the ones that MuRata Erie make.  I do
>heartily recommend them.
>--scott
>   (or you can always open up the can and put a varactor diode across the
>element, then adjust the bias of the varactor to slew it like a VCXO)

I was using the xtal oscillators. A VCO in a can or a xtal osc with an
input to a variactor diode would be good. Please flood my mailbox with
sources!
Dean Youngquist      [e-mail]

------------------------------

Date: (null)
From: (null)
TO:    ALL EMERGENCY MANAGEMENT AGENCIES/OFFICES VIA THE ARS
INFO:  ALL RACES OPERATORS IN CA (ALLCA: OFFICIAL)
       ALL AMATEURS U.S.         (@ USA: INFORMATION)
FROM:  CA STATE OFFICE OF EMERGENCY SERVICES (W6HIR @ WA6NWE.CA)
       2800 Meadowview Rd., Sacramento, CA  95832  [phone]
RACESBUL.166                                 DATE: April 22, 1991
SUBJECT:   How to help your Radio Officer

You emergency management agency managers frequently ask what your
Radio Officer should know. Many of the subjects have been covered
in past Bulletins. Several Radio Officers have recently suggested
the importance of their knowing about, understanding, and
cooperating with the other public safety communications managers
in your government. This will help to enable your volunteer
communications resources to fit it in better than if they are
held aside as a last resort, when all else fails, or a doomsday
resource. Such RACES units usually fade away not too long after
being organized. If they are an outside group, they may not be
equipped with adequate training and preconditioning from you and
your jurisdiction. Any volunteer is only as good as the training
he or she seeks and receives. We have heard from many Radio
Officers who support the premise that they are of more value when
they gain an understanding of the strengths and weaknesses of the
public safety communications systems in their area. They are
encouraged to become members of their local Associated Public-
Safety Communications Officers chapter. Some jurisdictions pay
the APCO dues for their RACES Radio Officer and broaden the scope
of their duties to include all volunteer communications services.
We know of several people who have entered the public safety
career field in this manner.

EOM

------------------------------

Date: 22 Apr 91 13:56:56 GMT
From: sdd.hp.com!uakari.primate.wisc.edu!news.larc.nasa.gov!grissom.larc.nasa.gov![e-mail]
To: [e-mail]

References <[e-mail]>, <[e-mail]>, <[e-mail]>
Reply-To : [e-mail] ( Scott Dorsey)
Subject : Re: Adjust frequency of4 terminal, rectanglular oscillators?

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>I wrote:
>>> For space saving and cost reasons I would like to use one of
>>> those small can oscillators with 4 terminals...
>>Very probably what you've got there is a crystal oscillator...
>
>My mistake; turns out there are other things that use the same package.

Nope, he's probably using a crystal oscillator as you said (or one with a
ceramic resonator).  What he should be using is a voltage-controlled
oscillator in a 4-pin can, like the ones that MuRata Erie make.  I do
heartily recommend them.
--scott
   (or you can always open up the can and put a varactor diode across the
element, then adjust the bias of the varactor to slew it like a VCXO)

------------------------------

End of Info-Hams Digest
******************************