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[AMPS] Good Meter vs CRT was Hot wire....

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Subject: [AMPS] Good Meter vs CRT was Hot wire....
From: krr2ak@juno.com (Jerry Devine)
Date: Wed, 28 Jul 1999 10:32:03 UTC
I was going to hold back longer but guess what?

>Peter G3RZP recently wrote:
>just because the Bird is accurate to 5%
>of FSD, it doesn't mean that the measurement over all is that good.

Your right Peter! Tom uses a good meter. It's accurate to only 8% or
he's holding something back thus far. Your 5% data is in error. As I
will point out later. But first bear with summarization and the
cronical and twisted humor bytes. Alot of this I wrote before your post.
I have a feeling Tom has been abducted by Aliens and has been implanted
with something or other.  Don't worry though, we'll get to the bottom
of it yet.

>Didn't bother to research who said this [sorry] wrote:
>>When the FCC measures power, they use a regular peak reading 
>>meter. .....

Yeah right.  I bet you beleived Alice in wonderland was based on a
true story too.  I think we can only count on true facts.

        1) They do measure power somehow.
        2) Their only concerned with over 1500w P.E.P. violations.
           (And for lower power violations I'll buy the meter method)
        3) And thats at the antenna load terminals.
        4) If their interested enough they will bring
           the proper tools to measure with.
        
The logic here is simple.  If I were an FCC officer. I would not want you
to question my methods of measurement.  And coming in with a BIRD 43xx
like
yours is a sure fire way to start a debate.  Anything less would be a
waste
of our time.  I would be a professional. And a perfectionist. Not to
mention
a royal pain in your you know what.  I would even measure and document
your
A.C. Mains total current draw while transmitting.  Being an Officer
allows
me to inspect every N-connector if I want to. The whole station.  In the
case of your A.C. mains a state licenced electrician would be employed
to check for hazzards before I started any measurements. I would probably
spend 6 to 8 hours at your site. And I would be looking for all sorts of
violations to hang you with. Afterall your going plead whatever the list
is
down come hearing time.

>ag6k wrote:
> ?  wanna guess how such meters are ultimately calibrated?.  

>Tom W8JI wrote:
>No need to guess. Bird calibrates them on a caloric standard. Not 
>a scope in sight.

Bifocals on /or/ off Tom? You didn't read the fine print their only
8% accurate. You can calibrate it with a sledge hammer for all care.
It's only gona do P.E.P. to 8%.  #4314B #4391A  And from my experience
has a hard time reaching for 5% in non P.E.P. measuring. Seeings how
their calorimeters are only 3% accurate. With that said, Do we see
1500 or 1620 P.E.P. or is it only 1380 P.E.P. I will further state
that my amp manufacture says and I quote:

"Every well informed operator should be familiar with measurement
 procedures and with mathematical calculations of power level.

 Whenever possible, an oscilloscope should be used to monitor
 peak power levels, since ordinary meters are unable to do so."

I can't find that anywhere or anything like it in the Ameritron
AL-82 book. Nor an accuracy claim for the P.E.P. meter it sports.
And that is a very cute design Tom, looks way better than the
Bird's unit.  Why I am not surprised?

>Now there is nothing wrong with using a scope, 

Everyone recesses for a massage down at DollyMae's Parlor...

>assuming you have 

Refreshed we return, we have hypothesize again, Tom? Any one get the
feeling 
were LAB RATS?

This isn't funny, who put the tack on Tom's chair?

>one with the required accuracy and resolution and a good load, 

Oh, Tom, your such a barrel with these meta-theta transducers
stuck on your forehead. Aren't they uncomfortable?

Now an antenna isn't a load, nor is a dummy load. We need a good load.
That's great, I guess we'll all wait for some E.T. to bring us one.

>but it is not a good instrument for use in antenna system to measure 
>power. 

I guess if you re-define them as an imperfect load Tom, your right. And
insert the other twist by now calling it a system of inferior elements.

>Errors in power readings occur at both the square of the 
>voltage reading error as well as proportional to load impedance 
>error.

>> ag6k wrote:
>> ?  and an ordinary wattmeter would not be subject to such errors, Tom?
  

> w8ji wrote:
>SWR error is minimized if you know how to use the meter Rich. 

> ag6k wrote:
>?  We are measuring power into a 50-ohm termination, Tom.  

Rules say at the antenna feed point, anything up there has to be
1500w P.E.P. absolute maximum. The FCC considers the antenna an
acceptable load, the amp does and so should we. It is real world
order, not New world order.. We can warm our feedlines all we want
till the antenna. Thats good news for folks in the KL7.  Measuring
flat out LAB power is different aswell. As it should be. I used to
race cars. What it's top speed is and what the driver can do behind
the wheel is two different issues. So is our world of power.

>w8ji wrote:
>You are, I am not. Some of my antennas are real close to 50 
>ohms, some are not.

I'm getting sea sick.  First they aren't any good then they are.
Now you see Tom, Now you don't.  

TAG --- Your IT!

But getting back to the real things:
And those are defined as errors now, Tom?
Are you sure that identified all of them, Tom? 

>There is absolutely nothing wrong with using a good meter. 

Now all of a sudden Agent 007 stands up, stretches, and then FARTS
really loud. And asks what's that peak out too Tom? And while
I'm up can I start passing out beer nuts and budweiser's now?

BTW what's the difference between a good meter and a watt meter?
And the difference between a good meter and an O'scope?
Who designed the good meter? Where can we buy one? Make one?
Seems your the only one with one Tom? And don't tell us it's
in the AL-82...

>A few people have wrongly assumed a storage system can't respond fast 
>enough, but that is certainly not correct. 

I think you meant "its - meaning the good meter's - storage system
can't..."

A few people Tom?  Okay I guess I can buy that. Because a few people that
were in my H.S. physics class room got extra special treatment as I
remember.  
They were the ones with pocket protectors and taped bifocals...You also
are 
saying the rest of the people didn't assume anything! Isn't that like
saying 
"I prefer to be assimilable." ? 

>The storage system has to track the envelope change rate that follows
audio, 
>not the RF cycle change rate. A meter with directional coupler also
remains 
>accurate over reasonable load impedance errors. You simply 
>deduct reflected power from forward power.
>
>You read reflected power near full scale using the proper slug, and 
>subtract reflected power from forward. The result is the actual 
>power keeping in mind the directivity error of the slug and the 
>calibration errors. 

> ag6k wrote:
>?  I don't believe that its all that simple.  

Oh I see Tom,  we can't deduct lead inductance and various different
sources
of stray capacitance and other variable errors exist all while you argue
with
your slide rule. And further both instruments are equals except the good
meter is better than any other. But we can now use a directional coupler
because
it ignores reasonable well as does the good meter in the impedance errors
only
arena.  Where is all the scientific evidence you bolstered against the
scope?
We can see quite easily how well ur selling us less educational
requirements
needed to use meters. 

The no-coders, novices, and Techie's in the room start clapping!

Hello folk's Tom's missing something he identified earlier as an error.
And I'll bet he missed a few errors. 

But because the good ship lolly pop meter doesn't see the other errors 
it's okay to just deduct a real power. 

I say this is still flawed! Not a good enough answer. Everything has
to be accounted for Tom. This isn't as easy as the IRS's EZ-FORM.

>Outgoing power readings include both forward and reflected power 
>that was "bounced" off the PA output port. 

And I thought it checked into the tankard to hang out and have a few...
But I beleive it bounced off of there for now.  Somehow this has
a familar ring to it...

>That's why directional coupler wattmeters read higher when the load has
a 
>high SWR and the transmitter is matched to the new feedline impedance. 
>Reverse power reads only the reflected power, so you can simply subtract

>the reflected power out from the forward reading and you have true 
>forward power.

Within 8% with a Bird 4314B. All measurements. So you could have up to
16%
total error in a >1:3.0:1v.s.w.r., with two different peak reading
values.  And thats before we even consider all the variables you missed
that error you. 

It's got be real love Tom or no Love at all! The F.C.C. isn't interested
in your approximations. And personally neither am I. 1500 watts P.E.P.
no 1515w P.E.P. (1%) at the antenna feed point.  The most we could run
with your methods under worse case is 1260w P.E.P. to be safe.
And under the best conditions we could run at 1620w P.E.P. pushing 
limits and safely only 1380w P.E.P.

I side with Rich and my amp manufacture aswell as my better judgement.
And I don't really care if you want to attach a 50ohm load instead
of the antenna it makes no difference. Your still way off.

>Either way works, both models are OK. Virtually all textbooks 
>explain it more accurately and in better detail, but that is roughly 
>what goes on.

Either way doesn't work and here's why:
Rubber Ducks work and are models. Ok. But some how the wild ones in my
back yard won't mate with it. In fact they ignore it. Just like I'm 
going to do with your methods of madness, thus far.

Virtual Reality won't work here, your on the wrong reflector. We want to
know who these other experts are Tom.  Don't protect them look what they
have done to you.  And us! Were charged with the duty of repairs.

>Some wattmeters do this automatically.

I'll bet not one designed by w8ji. This is alot like saying "Some where 
over the rainbow", we'll find the land of Oz.

Mean while Elvis is making a new record, Tom has patented Deductible
Power 
Clauses.  D.P.C., very similar to Santa Clauses. 

See you in the tankards and pile ups. 

73,    Jerry                                     krr2ak@juno.com
[text|uuencode|59kb ea]                                                  
        'Our people are warriors,  often savage, but we are also many
other pleasant     things'    "And I come back to find the stars
misplaced & the smell of a world that has burned."   Jimi Hendrix 1967.

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