Ham Radio/Ham Radio CD-ROM (Emerald Software) (1995).ISO/news/ih91270b/ih91276.txt

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Subject: Info-Hams Digest V91 #276
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Info-Hams Digest            Sat,  6 Apr 91       Volume 91 : Issue 276

Today's Topics:
                      2m thru-glass ant question
                 Antenna Matching Gedanken Experiment
                            ATV: AM or FM
                            HF rig names?
                    Icom R-1 Undocumented features
                      Info-Hams Digest V91 #267
                        Licensing Philosophy?
                                 P40V
              PROPAGATION FORECAST BULLETIN 12  ARLP012
                    Specs for Boschert PWR Supply
       The first No-Code Ham is........(DRUMROLL)..... (2 msgs)

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: 5 Apr 91 21:45:18 GMT
From: hpl-opus!hpnmdla![e-mail]
Subject: 2m thru-glass ant question
To: [e-mail]

In rec.radio.amateur.misc, [e-mail] (John McCombie) writes:

>A while back I posted an article about thru-the-glass 2m antennas for
>one's car.  I bought an Antenna Specialists antenna at the local ham
>radio emporium, installed it and it works wonderfully.

>... The antenna I bought
>doesn't attach anything to the chassis of the car--the coax attaches
>to a small box on the inside of the car which electrically couples to
>the antenna, but there are no connections to the chassis at all.
>[BTW, I'm running a HT off of batteries, so there is no connection to
>the chassis through, say, the -ve power connection.]

>Why and/or how does my antenna work?

I think the answer is that a bent coathanger will work as an antenna too.
If the repeater is good and strong at your location, it may appear to work
fine.  The only way to tell is to do a side-by-side comparison with an
antenna of known gain.

With no ground, the coax shield is acting as your "ground plane."
I expect there is considerable radiation from the shield inside the car.
You will probably get a more consistent omni-directional pattern with
the shield grounded to the car body right at the window.

In my opinion, thru-glass antennas are compromise antennas.  But the
difference between a "good" antenna and a compromise antenna is probably
only 3-10 dB, which would be barely noticed in normal operation, so
the convenience of the thru-glass antenna may well be justified.

AL N1AL

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

Date: 5 Apr 91 21:38:25 GMT
From: hpl-opus!hpnmdla![e-mail]
Subject: Antenna Matching Gedanken Experiment
To: [e-mail]

In rec.radio.amateur.misc, [e-mail] (Ross Alexander) writes:

>Say one has a rig driving a chunk of (lossless) coax, said coax being
>terminated in either a dead short or an open - the intent is to get
>perfect reflection.  OK, so the SWR is infinite.  All the power stays
>in the transmitter.  Things get hot!

Let's say you add an antenna tuner to the shorted coax and manage to
tune it to 50 ohms.  The transmitter will be perfectly happy.  What is
happening is the power is being dissipated in the loss resistance of
the coax and tuner.  With a more reasonable load, say 3:1 SWR, the tuner
losses should be low, and you get nearly full power to the antenna.

Tube-type transmitters have an adjustible matching network built into
the output.  There won't likely be enough adjustment range to allow
proper loading into a shorted coax.  But say your antenna has a 3:1 SWR,
and the matching network has enough range to load up properly into this
antenna.  This means the final amplifier tube is "seeing" its proper
load impedance. The tube it perfectly happy.  There may be more
dissipation in the matching coil due to higher circulating currents,
and there will be more loss in the feedline than with a 50-ohm antenna,
but if these losses are low enough to begin with, you may have a perfectly
viable system.

AL N1AL

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

Date: 6 Apr 91 18:44:00 GMT
From: swrinde!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!att!emory!wa4mei!ke4zv![e-mail]
Subject: ATV: AM or FM
To: [e-mail]

In article <[e-mail]> [e-mail] (Phil Howard KA9WGN) writes:
>
>Not necessarily.  Given that the lower frequency portions of the video
>get more benefit from a constant deviation, being as the modulation index
>is much higher, I'd expect that the high average power level is effectively
>being dedicated unevenly, favoring the lower frequencies.

But this is very desirable for video. Most of the important parts of the
signal are at the low frequencies. The vital sync signals and the gross
picture features are low frequency. The very fine picture detail is at
the highest end of the video frequency spectrum. Noise here is not very
noticeable. In fact we often will delibrately introduce some high frequency
noise into a picture during the production process to mask some picture
defect. It should be noted that AM modulation is designed to favor the
sync components of the video. Peak modulation is at sync tip, black is
at 70% and peak white is at 12.5%. Fine details in the picture tend not
to have a very high depth of modulation and hover near the peak white
value. Therefore AM TV also favors the lower frequency components by
design. One exception to this low depth of modulation for high frequency
components occurs in some character generators. They produce very high
rise time, very deeply modulated edges on the lettering. In AM signals
this often results in overshoots beyond the 12.5% point all the way down to
the zero point that will introduce "sync buzz" in the intercarrier audio.
In FM signals this results in the familiar black sparklies on picture
edges. Many stations have resorted to low pass filters on their character
generators to remove this annoyance. The filter slows the risetime of
the edges and reduces their depth of modulation. The production department
hates this because it makes keying the signal harder. So some stations
filter their video at the transmitter input. Engineers hate this because
it makes *all* video look softer than it should.

Gary KE4ZV

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

Date: 7 Apr 91 02:29:29 GMT
From: maverick.ksu.ksu.edu![e-mail]
Subject: HF rig names?
To: [e-mail]

In <[e-mail]> [e-mail] (Gary Coffman) writes:
>In article <[e-mail]> [e-mail] (Diana L. Syriac) writes:
>>....  Do hams use a transceiver AND a separate receiver?

>.... A few top of the line transceivers offer dual receive so even
>this excuse to have separates is coming to an end.

Hmmnn.  I wasn't aware that the old (1975?) TenTec Triton IV was
ever considered "top of the line" even back then.  But with an
(optional) external VFO it has dual-frequency receive.
--Myron.
--
# Myron A. Calhoun, Ph.D. E.E.; Associate Professor   [phone] home
#  INTERNET:  [e-mail] (129.130.10.2)                532-6350 work
#      UUCP:  ...rutgers!ksuvax1!harry!mac                  532-7353 fax
# AT&T Mail:  attmail!ksuvax1!mac                   W0PBV @ K0VAY.KS.USA.NA

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

Date: 7 Apr 91 03:51:10 GMT
From: [e-mail]
Subject: Icom R-1 Undocumented features
To: [e-mail]

The incredible Icom R-1 scanner is rumored to have a few undocumented
features. Supposedly some key sequences can disable AGC as well as
a few other tricks. Has anyone managed to figure these out yet ?
Any information would be greatly appreciated.
                                                 -Wayne

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

Date: 7 Apr 91 04:32:00 GMT
From: [e-mail]
Subject: Info-Hams Digest V91 #267
To: [e-mail]

> I'm interested in the state-of-the-art computer tools for
> prediction of propagation for HF via the ionosphere.  I suppose
> this would include through at least 6 m, and possibly up to
> 100 MHz.
> The thing that I have against these programs is that they use
> solar flux alone.  As we've all seen lately, that's only half
> of the story.

Unfortunately, the truth is that solar flux may be *none* of
the story with regard to 6M long skip.  In order to predict
a from b successfully, there has to be a correlation between
a and b.  Smoothed sun spot numbers are averaged over six
months.  That means you don't get a number for this month
until six months from now.  Correlates with a lot of things,
but not useful in real time.  Ottawa measures the solar flux
(radio noise) at 2800 Mhz daily.  These are the numbers that
WWV broadcasts.  The result is a real-time number that
correlates roughtly with the SSN (smoothed sunspot nr).
However, it appears that the emission mechanisms which
produce the 2800 Mhz noise are poorly correlated with the
radiation which ionizes the ionosphere w/re 6M and hence do
not effectively predict 6M openings. (My personal
observation is that the correlation is not great even on
10M.)

This is why any good prediction pgm doesn't give you values
above 30Mhz -- the author knows they would be meaningless. I
suggest you see the article by Shel Remington, NI6E/KH6, in
the April issue of DX Magazine "Solar Flux and Six Meters.

My favorite propagation pgm is W6EL's Miniprop.  The author,
Shel (aonther one), is known for his saying "Muf is not
enuf".  This pgm has helped me shag a couple of rare ones by
telling me things other propagation pgms didn't.

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

Date: 5 Apr 91 17:34:30 GMT
From: hpfcso!hpfcdc![e-mail]
Subject: Licensing Philosophy?
To: [e-mail]

>Then he made two more points: with the state of modern gear, one or two can
>fix their own rigs without a factory, and the rigs do everything.  The
>other point was that the government doesn't restrict the public's access to
>operating motor vehicles to those who demonstrate basic mechanic's skills.

Point one ignores several realities.  Three counterpoints.  1.  Old gear
exists, which is serviceable without a high degree of technical
expertise.  2.  New gear is simply more complicated, but not impossible
to service and uses many old principles.  There are only so many ways to
make an oscillator.  3.  Modern gear still uses low-tech peripherals,
like keyers, filters, linear amplifiers, antenna couplers, and antennas,
which are within the realm of construction possibilities.

Point two has been discussed before.  Ham radios have a lot of knobs and
blinkenlights, both inside and outside the cabinet, which are beyond the
ability of the average automobile driver to properly use.  Hams are
allowed to modify their equipment in ways that would make their gear
a hazard to themselves and others.


Many non-hams only see the "operator" function of the hobby.  They need
to be gently reminded that many of us operate because it's the only way
to test our homebrew equipment.  I suppose even contesters (The Ultimate
Operators) can be thought of as a gigantic test team for the major
equipment manufacturers.

Perry Scott / KF0CA

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

Date: 3 Apr 91 23:09:37 GMT
From: hpda!hpcupt1![e-mail]
Subject: P40V
To: [e-mail]

Actually P40V is not the NCCC. P40V is owned by Carl Cook who happens
to be a member of NCCC.  But NCCC does have many top operators in its
membership.
Jim, WA6SDM
[e-mail]

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

Date: 6 Apr 91 23:30:34 GMT
From: sdd.hp.com!samsung!umich!sharkey!nstar!towers!bluemoon!n8emr!@ucsd.edu
Subject: PROPAGATION FORECAST BULLETIN 12  ARLP012
To: [e-mail]

==============================================================
|     Automatic relayed from packet radio via              |
| N8EMR's Ham BBS, 614-895-2553 1200/2400/9600/V.32/PEP/MNP5 |
==============================================================

ZCZC AP68
QST DE W1AW
PROPAGATION FORECAST BULLETIN 12  ARLP012
FROM TAD COOK, KT7H, SEATTLE, WA
APRIL 6, 1991
RELAYED BY KB8NW/OBS & BARF-80 BBS
TO ALL RADIO AMATEURS

The solar flux stayed under 200 over the past week, but increasing
flare activity caused more of the unstable conditions that we have
seen in past weeks.  Although not as disturbed as last week's
conditions, K indices of five have been reported on every day since
April 1.

Look for more unsettled to active geomagnetic conditions, gradually
tapering off with a declining A index and rising solar flux.  The
flux value should rise from 200 to around 225 over the next week,
and the A index may fall off to about 10.  The solar flux is
expected to peak for the short term around April 19 or 20.

Students of HF radio propagation will be interested to read an
article on forecasting by W3EP and N8LSQ in April QST, which
discusses some of the ways radio amateurs can use publicly available
solar data to do their own short and mid term propagation forecasts.

American sunspot numbers for March 21 through 27 were 167, 167, 177,
138, 145, 151 and 150, with a mean figure of 156.4.  For the week
March 28 through April 3, they were 121, 111, 95, 87, 82, 99 and
108, with a mean of 100.4.

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

Date: 6 Apr 91 23:45:49 GMT
From: fernwood!uupsi!cci632![e-mail]
Subject: Specs for Boschert PWR Supply
To: [e-mail]

Hello All...

My printer's power supply died. I checked my local sources and can't get
any kind of specs for the supply. The manufacturer is no longer listed
in Thomas register, and the phone number printed on the unit is no longer
assigned. I'm not looking to fix it, just replace the supply with a new one
with the same voltages and amps. If anyone has an old catalog and can do a
quick lookup for the power out specs, drop me a line please.

BOSCHERT model #XL200 - 3603/4603 300Watt 120 v in, (+12, +5, ?? out).

Any help, would be greatly appreciated. Please E-mail to [e-mail].

Thnx,

Dave Roland

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

Date: 7 Apr 91 00:23:41 GMT
From: sdd.hp.com!zaphod.mps.ohio-state.edu!ub!csn!boulder!tigger![e-mail]
Subject: The first No-Code Ham is........(DRUMROLL).....
To: [e-mail]

In article <[e-mail]> [e-mail] (Bruce B. Sawyer) writes:
>In article <[e-mail]> [e-mail] (Paul W. Schleck KD3FU) writes:
>
>>... will have a unique place in ham history as the first U.S. Amateur
>>to become licensed without demonstrating proficiency in International Morse
>>Code.  I think a hearty congratulations to Robert is in order.
>
>Give me a break.  Congratulations for NOT knowing something?  If I'd come in
>by this back door route I sure wouldn't be out advertising it in public.  Let
>the guy take his rightful place next to the mail-order Ph.D's.
>                                                         AA6KX

In case anyone was wondering why an intelligent young man such as myself,
one who has completed _graduate_ level courses in EE, math, physics, and
computer science doesn't have a ham license, ... and in fact would shed
few tears (most days) if amateur radio was yanked off the airwaves, read
that last statement a few times.

SMUG and ARROGANT don't begin to cover it.

I've been watching this newsgroup and just about decided my previous
encounters with Hams had been misleading.  I was wrong.  With people like
Mr. Sawyer, it won't be long before the FCC has a hard time defending
ham frequency allocations.

At least the FCC can apply the "reasoning" implied above and make
the requirements for Ham licenses a little bit tighter.

So, I would recommend you grab a graduate level texts on EM fields,
waveguides, non-linear optics, quantum mechanics, metallurgy, data
compression, information theory, atmospheric models, plus a number of
additional items which I can't recall off the top of my head.

Oh yeah, be prepared to demonstrate not only Morse code at 40 wpm, but
also to touch type at 100+.  I can, and since packet radio uses
keyboards I can _REQUIRE_ you to as well, using your "reasoning."

All e-mail replies will be forwarded to /dev/null unread.

 ..   ------------------------+-----------------------------------------
`/\'  Bear Giles          |  Religion is a defense mechanism against
(__)  [e-mail] |  religious experiences.        -- Carl Jung
      ------------------------+-----------------------------------------

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

Date: 7 Apr 91 03:31:18 GMT
From: sdd.hp.com!zaphod.mps.ohio-state.edu!magnus.acs.ohio-state.edu!csn!boulder!tigger![e-mail]
Subject: The first No-Code Ham is........(DRUMROLL).....
To: [e-mail]

In article <[e-mail]> [e-mail] (Bruce B. Sawyer) writes:
>In article <[e-mail]> [e-mail] (Paul W. Schleck KD3FU) writes:
>
>Give me a break.  Congratulations for NOT knowing something?  If I'd come in
>by this back door route I sure wouldn't be out advertising it in public.  Let
>the guy take his rightful place next to the mail-order Ph.D's.
>                                                         AA6KX

Amplification on my earlier post:

The purpose for Amateur Radio is (from the ARRL and originating legislation)

1) Education and encouragement of youth to pursue technical careers.

Towards that end a number of licenses were created, with additional
privledges granted for demonstrated knowledge.  That is fairly standard --
you start people out with something simple, and as they learn, you give
them more options.

Yet is it only Hams which are hung up on a person's license.  I know NO
private pilots who get harrassed by commerical pilots _SOLELY_ because
they lack a commercial license.   I know no divers who get harrassed by
dive instructors _SOLELY_ because they lack instructor's certificates.
I know of no drivers who get harrassed by professional drivers _SOLELY_
because they lack a courier's license.

Yet Mr. Sawyer (and countless other Hams) feel entitled to DENIGRATE ALL
HOLDERS OF "INFERIOR" LICENSES _SOLELY_ BECAUSE THEY HOLD "SUPERIOR"
lICENSES.

Mail order Ph.D. indeed!

There is a damn good reason for novice licenses -- there is absolutely
no way on earth that a 12-year-old will be able to earn an advanced-extra
Class license.  Yet many hams seem to think otherwise.

2) Research and development of new technology.

A major area of research and development today is in packet radio.
Packet radios are physically incapable of transmitting or receiving
morse code.  They have no speakers, no microphones, and no way of
attaching them.  (I am refering to a _pure_ packet station, not one
constructed from separate PCs and transceivers).

Yet many Hams feel a moral imperative to demand that all operators
of these stations display knowledge which has _absolutely_ no value
to them.

Rather than recognize this, and the fact that these people's time would
be better spent learning more about computers and digital transmissions,
they demand training in obsolete technology.

How is this different than the Department of Motor Vehicles demanding
you demonstrate _HORSEMANSHIP_ before issuing an automobile license?

Finally, for someone interested in R&D a license is a _tool_, nothing
else.  Nobody will waste precious time to get a license "higher" than
they require.

Not that you would know it after listening to some people....

3) Encouraging global understanding.

Talk to people in foreign countries!  Learn they are just like us!

Since many countries have dropped Morse code requirements, and many
American Hams appear to feel that this makes them morally superior,
no, it's MORALLY SUPERIOR, with the right to make malicious attacks on others
based solely on this, I fail to see how global understanding will be
improved.


Perhaps this is a general "attack on ignorance."  Fine, except there
are a _lot_ more things which are more useful than Morse code.  ANYTHING
is more useful to someone with a packet station.

Or perhaps this is the same philosophy which leads to 1000W linear
amps attached to CB radios.  Or the "I have a GENERAL LICENSE, jerk, so stop
whining when I blow away your puny little NOVICE signal!  Get a GENERAL
LICENSE yourself!" syndrome.

I realize that not all Hams are pompeous assholes.  But there are enough
of them (far more than I have found elsewhere) that I am signing off
ham radio for good.  It's just not worth the hassle.

But consider this carefully the next time the FCC threatens to restrict
Ham activity.  There are a lot of people who have good reason to dislike
Hams, and it's not the occasional unexplained interference.

 ..   ------------------------+-----------------------------------------
`/\'  Bear Giles          |  Religion is a defense mechanism against
(__)  [e-mail] |  religious experiences.        -- Carl Jung
      ------------------------+-----------------------------------------

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

Date: 5 Apr 91 14:31:55 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: Technician class (was No-Code Testing Questions)

>> What the FCC did is to CHANGE the requirements for the Technician class
>> license, so it's hard to imagine why they would want to create a new
>> name.  The existing name ("Technician") will do just fine.
>>     paul, ni1d
>
>My understanding is that there are in fact two Technician licenses:
>    Technician no-code (new no-code license)
>        Technician + code  (same as old Technician)
>So it seems reasonable to me that there should be two names.  I've read that
>they are simply called "Technician" and "Technician Plus Code".
>| Pete Stoppani          | [e-mail]                   |

Paul is right. And in point of fact Pete, there are now four "types"
of Technician license:
    Current: Technician (no code, vhf-only)
    Current: Technician (plus CSCE for code, all vhf, plus Novice hf)
    Recent:  Technician (all vhf, Novice hf, no CSCE (code as novice))
    Older:   Technician (vhf, Novice hf, has General written credit)

The comment regarding names was for informal purposes only! The license
is: Technician. Nothing less. Nothing more. (Time for .policy ??)
--
Ed Humphries                Texas Instruments, Inc. 512-250-6894
N5RCK                       Internet [e-mail]
-. ..... .-. -.-. -.-       Packet N5RCK@NA4M

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

Date: 6 Apr 91 19:47:29 GMT
From: swrinde!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!att!emory!wa4mei!ke4zv![e-mail]
To: [e-mail]

References <[e-mail]>, <[e-mail]>, <[e-mail]>
Reply-To : [e-mail] (Gary Coffman)
Subject : Re: Antenna Matching Gedanken Experiment

In article <[e-mail]> [e-mail] (Ross Alexander) writes:
>Lately there's been some talk in this group about antenna matching,
>SWR values, and so on.  Someone (sorry, didn't save the article)
>mentioned that SWR didn't really matter, since the reverse wave
>reflecting from a mismatched load just bounced off the transmitter as
>well, and that worrying about getting a low SWR was really not very
>important - all the power went out the antenna eventually.  I believe
>a book called `Reflections' was mentioned as an authority.

This is almost correct. To get the signal bounced back to the load
from the transmitter, the transmitter must be conjugate matched to
the complex impedance appearing at it's output terminals. The reason
there will be a complex impedance at the transmitter terminals  is
that *any* line that has a SWR other than 1:1 will act as a transmission
line transformer. The load impedance will be transformed to something
else at the transmitter end, and the line itself will represent a
reactance whose value will depend on it's length and the frequency
of operation. This transformation also works in reverse of course so
the reflected wave will now see a perfect match on the load end and
be totally absorbed by the load. A transmatch or a transmitter with
sufficient tuning range is needed to achieve conjugate match.

>Say one has a rig driving a chunk of (lossless) coax, said coax being
>terminated in either a dead short or an open - the intent is to get
>perfect reflection.  OK, so the SWR is infinite.  All the power stays
>in the transmitter.  Things get hot!

Very true because no real network can be designed to conjugate match
infinity or zero to a real value. These are singularities that cannot
be matched.

>Tying that back to the real world, it happens that for a while I was
>running an antenna that loaded well on 80, 40, 20, & 10 but very
>poorly on 15.  The fans in my rig ran much harder when working on 15.
>The heatsinks got hotter.  Perhaps my rig didn't read that book...

More likely your tuning network couldn't conjugate match the impedance
presented on 15 meters. This causes the transmitter to be operated off
tune and, of course, it gets hot and doesn't transfer much power.

Gary KE4ZV

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

Date: 7 Apr 91 02:29:53 GMT
From: usc!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!hpb.cis.pitt.edu![e-mail]
To: [e-mail]

References <[e-mail]>, <[e-mail]>, <[e-mail]>(
Subject : Re: Codeless = worthless? (was Re: The first No-Code Ham is)


   This topic seems more appropriate to rec.radio.amateur.policy.  I
think the discussion should be moved there.

73,
Harry Bloomberg WA3TBL
[e-mail] or
[e-mail]

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

Date: 6 Apr 91 18:21:45 GMT
From: swrinde!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!att!emory!wa4mei!ke4zv![e-mail]
To: [e-mail]

References <[e-mail]>, <[e-mail]>, <[e-mail]>p
Reply-To : [e-mail] (Gary Coffman)
Subject : Re: frequency standards

In article <[e-mail]> [e-mail] (Mike Morris) writes:
>
>I do not know how many stations use a rubidium standard as a transmitter
>frequency control, but it may be worth checking.

Not many stations use a rubidium standard for their transmitters. The FCC
required frequency tolerance for VHF TV transmitters is 1,000 hertz plus
or minus of the assigned frequency. This is a looser tolerance than that
of the color subcarrier (10 hz). Also quite a few stations do not operate
on the standard channels. The Gannett station in Atlanta operates with
a positive 10 khz offset from the standard channel.

Note that if you want to use the color subcarrier of a broadcast signal
as a reference, you must be very careful to only sample the subcarrier
during burst interval. The subcarrier is FM modulated to transmit hue
information and AM modulated to transmit color saturation information.
Only the burst is held to a constant amplitude and phase.

Some of you might be interested in knowing how we in the broadcast business
make sure that we are transmitting a signal within the legal limits.

To monitor our transmitters, we use specialized counters called station
monitors. The one at our Atlanta station is made by TFT. It has two counter
displays, nixie tubes no less, that show the deviation in hertz from our
assigned frequency of the visual and aural carriers. The TFT has a 10 Mhz
master clock output that we compare to WWV to assure the accuracy of
the counters. To measure our color subcarrier, we take raw subcarrier
out of our station master sync generator and feed it to an antique HP
frequency counter. The counter's master clock is calibrated against
WWV in a similar manner to the TFT's clock. We use an R390A and a
Tektronix 524 oscilliscope. If any of you have visited a broadcast
plant, you've probably noticed that the engineering departments rarely
throw away anything that works. The production department gets all the
new gee whiz toys while engineering is usually using twenty year old
equipment. It can be very frustrating to try to fix some new state of
the art production toy with stone age test equipment. On the other hand,
*our* equipment rarely breaks. :-)

Gary KE4ZV

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End of Info-Hams Digest
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