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Old October 17th 18, 09:26 AM posted to uk.radio.amateur,rec.radio.amateur.antenna
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On 17/10/2018 08:51, Spike wrote:

To bring this back to the issue at hand, I claimed that "I'd have to say
that none of what you say refutes my original contention that the
distant station, which after all is the one we are trying to communicate
with, will notice any difference to the received signal whether the
sending station's antenna was tuned with a 20c torch bulb or a $300 VNA"
and so far that still stands.


With all his blustering and gratuitous personal abuse, Lieberman
presents as the Yank version of M3OSN.

  #102   Report Post  
Old October 17th 18, 11:00 AM posted to uk.radio.amateur,rec.radio.amateur.antenna
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Spike wrote:

On 16/10/2018 14:38, Ralph Mowery wrote:
In article , lid
says...


Very interesting, but I'd have to say that none of what you say refutes
my original contention that the distant station, which after all is the
one we are trying to communicate with, will notice any difference to the
received signal whether the sending station's antenna was tuned with a
20c torch bulb or a $300 VNA. You touched on the main vagaries of the
system when you said "What I've found is that such side by side
comparisons do not account for variations in propagation, path,
interference, local noise, time of day, position of the moon, and other
factors beyond the operators control".


Sometimes it is who is doing the adjusting and not how good the
equipment is.


That's very true, of course. Some good equipment is in the 'wrong hands'.

Almost 40 years ago I started keeping a repeater on the air that was
started by someone else. My test equipment at that time was a VTVM, a
$ 25 Heathkit signal generator, old Oscilloscope, swr meter, and
frequency counter.


To tune the receiver my best 'signal generator' was a ham near the edge
of the repeater coverage. I would have him just to key down for a
minute or two at a time while I adjusted the receiver. Over the years a
better receiver and transmitter was installed. Now I have some very
good test equipment, but can not say the coverage of the repeater is
very much better. What little improvement is made is probably because
the radio equipment is better.


Thanks! That's just the sort of thing I was on about - in this case you
actually used a distant station to help with the set-up, and it worked well.

At that time one thing I did not try to adjust or check was the duplexer
as I did not think I could with what I had to work with. Many years ago
the tuning instructions for duplexers was to tune for maximum signal on
the pass and best rejection. As test equipment became better and priced
in range, the pass tuning change to using a return loss bridge and
SA/TG. This seems to work much better. I found the pass was broad and
you could usually give the tuning rod a turn or two without much effect,
but he RLB shows up in less than 1/2 of a turn. Does it make a
difference ? Probably not in effective coverage (it may extend the
range a foot or two,hi), but at least I know it tuned the best it can be
with what I have to work with.


One thing that does come with better test equipment is knowing that the
equipment is tuned so it meets or exceeds the specifications. Before
it was just a guess as if the equipment did or did not meet
specifications.


Quite so. But 'specifications' are often written with other things in
mind - compatibility, spurii, stability, etc, and not necessarily
anything at all to do with how the distant station receives/perceives
one's signal.


ISTR it being a licence condition that one checked all the above
periodically - more honoured in the breach, perhaps, with commercial
kit.

--

Roger Hayter
  #103   Report Post  
Old October 17th 18, 11:33 AM posted to uk.radio.amateur,rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Jan 2014
Posts: 329
Default 4NEC2?

Jeff Liebermann wrote:
On Tue, 16 Oct 2018 07:44:53 +0000, Spike
wrote:

Very interesting, but I'd have to say that none of what you say refutes
my original contention that the distant station, which after all is the
one we are trying to communicate with, will notice any difference to the
received signal whether the sending station's antenna was tuned with a
20c torch bulb or a $300 VNA. You touched on the main vagaries of the
system when you said "What I've found is that such side by side
comparisons do not account for variations in propagation, path,
interference, local noise, time of day, position of the moon, and other
factors beyond the operators control".


Perhaps an analogy might be useful. Instead of an HF radio, you're
dealing with your automobile. Under normal circumstances, it will get
you to work and back fairly efficiently. However, you notice that
your gasoline (petrol) mileage is not quite what you might expect. So,
you have a choice of mechanics. The first mechanic tunes the engine
with a light bulb, divining rod, magic incantations, and offers a
rather bizarre description of what work was done on the vehicle. The
second mechanic uses proper computerized test equipment to analyze the
situation, uses factory parts, and delivers the car with a detailed
printout of what was done, what changes were made, what parts were
used, and a before-after gas mileage comparison performed on a
dynamometer.

Now, which mechanic would you prefer? Your car will still go to work
and back in some manner. The second mechanic will cost more, because
he has to pay for all the expensive equipment and genuine parts. If
you're impoverished, obviously the first mechanic will be the only
available choice, but assuming you plan to keep the vehicle, one might
suspect it is a bad long term solution.

From my perspective, both professional and as a ham, I deal in
numbers. I can tell by looking at the numbers what is happening and
what needs to be done. I have a small collection of aging test
equipment to help me generate the numbers. Light bulbs do not
generate numbers and are therefore (in my never humble opinion)
useless and worthless.

However, I will concede that if your intent is "to be able to transmit
signals intended to be received by another station", a light bulb is
sufficient to determine that your transmitter is spewing RF, spurs,
harmonics, and noise into an antenna-like device that is either
radiating the RF, absorbing it into heat, or reflecting it back to the
transmitter (because the light bulb indicates the same in both
directions).


Burt won’t appreciate being given an absolute schooling from Jeff here.

--
STC / M0TEY /
http://twitter.com/ukradioamateur
  #104   Report Post  
Old October 17th 18, 11:33 AM posted to uk.radio.amateur,rec.radio.amateur.antenna
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Posts: 329
Default 4NEC2?

Gareth's Downstairs Computer
wrote:
On 16/10/2018 20:47, Jeff Liebermann wrote:

Let me bring it closer to home. You purchased an expensive HF radio
with all the bells and whistles. It's out of warranty and you need
something fixed. Would you send it to 1) the factory, 2) an
authorized repair station, 3) a rebuilder in China, 4) the ham
equivalent of the shade tree mechanic, or 5) the teenager next door?


If you send to anyone other than yourself then you are not
a real radio ham or radio amateur.

A CBer, probably.


G is for gurgler.

--
STC / M0TEY /
http://twitter.com/ukradioamateur
  #105   Report Post  
Old October 17th 18, 11:36 AM posted to uk.radio.amateur,rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Feb 2014
Posts: 180
Default 4NEC2?

On 17/10/2018 10:00, Roger Hayter wrote:
Spike wrote:


On 16/10/2018 14:38, Ralph Mowery wrote:
In article , lid
says...


Very interesting, but I'd have to say that none of what you say refutes
my original contention that the distant station, which after all is the
one we are trying to communicate with, will notice any difference to the
received signal whether the sending station's antenna was tuned with a
20c torch bulb or a $300 VNA. You touched on the main vagaries of the
system when you said "What I've found is that such side by side
comparisons do not account for variations in propagation, path,
interference, local noise, time of day, position of the moon, and other
factors beyond the operators control".


Sometimes it is who is doing the adjusting and not how good the
equipment is.


That's very true, of course. Some good equipment is in the 'wrong hands'.


Almost 40 years ago I started keeping a repeater on the air that was
started by someone else. My test equipment at that time was a VTVM, a
$ 25 Heathkit signal generator, old Oscilloscope, swr meter, and
frequency counter.


To tune the receiver my best 'signal generator' was a ham near the edge
of the repeater coverage. I would have him just to key down for a
minute or two at a time while I adjusted the receiver. Over the years a
better receiver and transmitter was installed. Now I have some very
good test equipment, but can not say the coverage of the repeater is
very much better. What little improvement is made is probably because
the radio equipment is better.


Thanks! That's just the sort of thing I was on about - in this case you
actually used a distant station to help with the set-up, and it worked well.


At that time one thing I did not try to adjust or check was the duplexer
as I did not think I could with what I had to work with. Many years ago
the tuning instructions for duplexers was to tune for maximum signal on
the pass and best rejection. As test equipment became better and priced
in range, the pass tuning change to using a return loss bridge and
SA/TG. This seems to work much better. I found the pass was broad and
you could usually give the tuning rod a turn or two without much effect,
but he RLB shows up in less than 1/2 of a turn. Does it make a
difference ? Probably not in effective coverage (it may extend the
range a foot or two,hi), but at least I know it tuned the best it can be
with what I have to work with.


One thing that does come with better test equipment is knowing that the
equipment is tuned so it meets or exceeds the specifications. Before
it was just a guess as if the equipment did or did not meet
specifications.


Quite so. But 'specifications' are often written with other things in
mind - compatibility, spurii, stability, etc, and not necessarily
anything at all to do with how the distant station receives/perceives
one's signal.


ISTR it being a licence condition that one checked all the above
periodically - more honoured in the breach, perhaps, with commercial
kit.


That's the sort of road that Liebermann wanted to take the discussion
down; an interesting topic but not the issue under discussion.


--
Spike

"Nearly all men can stand adversity,
but if you want to test a man's character,
give him an internet group to manage"



  #106   Report Post  
Old October 17th 18, 02:04 PM posted to uk.radio.amateur,rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Jan 2015
Posts: 181
Default 4NEC2?

Stephen Thomas Cole wrote:

Jeff Liebermann wrote:
On Tue, 16 Oct 2018 07:44:53 +0000, Spike
wrote:

Very interesting, but I'd have to say that none of what you say refutes
my original contention that the distant station, which after all is the
one we are trying to communicate with, will notice any difference to the
received signal whether the sending station's antenna was tuned with a
20c torch bulb or a $300 VNA. You touched on the main vagaries of the
system when you said "What I've found is that such side by side
comparisons do not account for variations in propagation, path,
interference, local noise, time of day, position of the moon, and other
factors beyond the operators control".


Perhaps an analogy might be useful. Instead of an HF radio, you're
dealing with your automobile. Under normal circumstances, it will get
you to work and back fairly efficiently. However, you notice that
your gasoline (petrol) mileage is not quite what you might expect. So,
you have a choice of mechanics. The first mechanic tunes the engine
with a light bulb, divining rod, magic incantations, and offers a
rather bizarre description of what work was done on the vehicle. The
second mechanic uses proper computerized test equipment to analyze the
situation, uses factory parts, and delivers the car with a detailed
printout of what was done, what changes were made, what parts were
used, and a before-after gas mileage comparison performed on a
dynamometer.

Now, which mechanic would you prefer? Your car will still go to work
and back in some manner. The second mechanic will cost more, because
he has to pay for all the expensive equipment and genuine parts. If
you're impoverished, obviously the first mechanic will be the only
available choice, but assuming you plan to keep the vehicle, one might
suspect it is a bad long term solution.

From my perspective, both professional and as a ham, I deal in
numbers. I can tell by looking at the numbers what is happening and
what needs to be done. I have a small collection of aging test
equipment to help me generate the numbers. Light bulbs do not
generate numbers and are therefore (in my never humble opinion)
useless and worthless.

However, I will concede that if your intent is "to be able to transmit
signals intended to be received by another station", a light bulb is
sufficient to determine that your transmitter is spewing RF, spurs,
harmonics, and noise into an antenna-like device that is either
radiating the RF, absorbing it into heat, or reflecting it back to the
transmitter (because the light bulb indicates the same in both
directions).


Burt won't appreciate being given an absolute schooling from Jeff here.


I don't appreciate an interesting discussion being interpreted as a
schoolyard fight by ignorant troublemakers like you and Gareth.

--

Roger Hayter
  #107   Report Post  
Old October 17th 18, 03:20 PM posted to uk.radio.amateur,rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Apr 2015
Posts: 160
Default 4NEC2?


"Roger Hayter" wrote in message
...
Stephen Thomas Cole wrote:

Jeff Liebermann wrote:
On Tue, 16 Oct 2018 07:44:53 +0000, Spike
wrote:

Very interesting, but I'd have to say that none of what you say
refutes
my original contention that the distant station, which after all is
the
one we are trying to communicate with, will notice any difference to
the
received signal whether the sending station's antenna was tuned with a
20c torch bulb or a $300 VNA. You touched on the main vagaries of the
system when you said "What I've found is that such side by side
comparisons do not account for variations in propagation, path,
interference, local noise, time of day, position of the moon, and
other
factors beyond the operators control".

Perhaps an analogy might be useful. Instead of an HF radio, you're
dealing with your automobile. Under normal circumstances, it will get
you to work and back fairly efficiently. However, you notice that
your gasoline (petrol) mileage is not quite what you might expect. So,
you have a choice of mechanics. The first mechanic tunes the engine
with a light bulb, divining rod, magic incantations, and offers a
rather bizarre description of what work was done on the vehicle. The
second mechanic uses proper computerized test equipment to analyze the
situation, uses factory parts, and delivers the car with a detailed
printout of what was done, what changes were made, what parts were
used, and a before-after gas mileage comparison performed on a
dynamometer.

Now, which mechanic would you prefer? Your car will still go to work
and back in some manner. The second mechanic will cost more, because
he has to pay for all the expensive equipment and genuine parts. If
you're impoverished, obviously the first mechanic will be the only
available choice, but assuming you plan to keep the vehicle, one might
suspect it is a bad long term solution.

From my perspective, both professional and as a ham, I deal in
numbers. I can tell by looking at the numbers what is happening and
what needs to be done. I have a small collection of aging test
equipment to help me generate the numbers. Light bulbs do not
generate numbers and are therefore (in my never humble opinion)
useless and worthless.

However, I will concede that if your intent is "to be able to transmit
signals intended to be received by another station", a light bulb is
sufficient to determine that your transmitter is spewing RF, spurs,
harmonics, and noise into an antenna-like device that is either
radiating the RF, absorbing it into heat, or reflecting it back to the
transmitter (because the light bulb indicates the same in both
directions).


Burt won't appreciate being given an absolute schooling from Jeff here.


I don't appreciate an interesting discussion being interpreted as a
schoolyard fight by ignorant troublemakers like you and Gareth.

what was interesting about it ?.....


  #108   Report Post  
Old October 17th 18, 03:32 PM posted to uk.radio.amateur,rec.radio.amateur.antenna
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Posts: 180
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On 17/10/2018 14:20, Jim GM4DHJ ... wrote:
"Roger Hayter" wrote in message
Stephen Thomas Cole wrote:


Jeff Liebermann wrote:
On Tue, 16 Oct 2018 07:44:53 +0000, Spike
wrote:


Very interesting, but I'd have to say that none of what you say
refutes
my original contention that the distant station, which after all is
the
one we are trying to communicate with, will notice any difference to
the
received signal whether the sending station's antenna was tuned with a
20c torch bulb or a $300 VNA. You touched on the main vagaries of the
system when you said "What I've found is that such side by side
comparisons do not account for variations in propagation, path,
interference, local noise, time of day, position of the moon, and
other
factors beyond the operators control".


Perhaps an analogy might be useful. Instead of an HF radio, you're
dealing with your automobile. Under normal circumstances, it will get
you to work and back fairly efficiently. However, you notice that
your gasoline (petrol) mileage is not quite what you might expect. So,
you have a choice of mechanics. The first mechanic tunes the engine
with a light bulb, divining rod, magic incantations, and offers a
rather bizarre description of what work was done on the vehicle. The
second mechanic uses proper computerized test equipment to analyze the
situation, uses factory parts, and delivers the car with a detailed
printout of what was done, what changes were made, what parts were
used, and a before-after gas mileage comparison performed on a
dynamometer.


Now, which mechanic would you prefer? Your car will still go to work
and back in some manner. The second mechanic will cost more, because
he has to pay for all the expensive equipment and genuine parts. If
you're impoverished, obviously the first mechanic will be the only
available choice, but assuming you plan to keep the vehicle, one might
suspect it is a bad long term solution.


From my perspective, both professional and as a ham, I deal in
numbers. I can tell by looking at the numbers what is happening and
what needs to be done. I have a small collection of aging test
equipment to help me generate the numbers. Light bulbs do not
generate numbers and are therefore (in my never humble opinion)
useless and worthless.


However, I will concede that if your intent is "to be able to transmit
signals intended to be received by another station", a light bulb is
sufficient to determine that your transmitter is spewing RF, spurs,
harmonics, and noise into an antenna-like device that is either
radiating the RF, absorbing it into heat, or reflecting it back to the
transmitter (because the light bulb indicates the same in both
directions).


Burt won't appreciate being given an absolute schooling from Jeff here.


I don't appreciate an interesting discussion being interpreted as a
schoolyard fight by ignorant troublemakers like you and Gareth.


what was interesting about it ?.....


The clash of cultures between the open-minded out-of-the-box thinker,
and a rules-and-regulations-trump-everything engineer. We have the
latter type on UKRA too, more's the pity. Then there's those that don't
know a sideband from a sideburn, waving their 'Vouvray for our side'
banners. In all senses of the word.


--
Spike

"Nearly all men can stand adversity,
but if you want to test a man's character,
give him an internet group to manage"

  #109   Report Post  
Old October 17th 18, 04:00 PM posted to uk.radio.amateur,rec.radio.amateur.antenna
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Posts: 1,332
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On Wed, 17 Oct 2018 08:48:04 +0100, Gareth's Downstairs Computer
wrote:

On 16/10/2018 20:47, Jeff Liebermann wrote:

Let me bring it closer to home. You purchased an expensive HF radio
with all the bells and whistles. It's out of warranty and you need
something fixed. Would you send it to 1) the factory, 2) an
authorized repair station, 3) a rebuilder in China, 4) the ham
equivalent of the shade tree mechanic, or 5) the teenager next door?


If you send to anyone other than yourself then you are not
a real radio ham or radio amateur.


Are you suggesting that you have the ability to repair a modern HF
radio? Do you have the equipment? Do you have the knowledge? I have
both and believe me, it's often very difficult. Today's electronics
is not made to be easily repaired. Much of the stuff I fix was sent
to me after some ham attempted to fix it themselves. Usually, they
won't admit it. On the repair bench right now is an Astron power
supply, an MFJ-259 antenna analyzer, two HP5300 series counters, and
unfortunately, my IFR-1500 service monitor. All of them are the
results of botched repairs. Can you do better? After you fail, which
of the above 5 choices would be your next step? Or would you just
sell the radio and pretend there was nothing wrong?

A CBer, probably.


It's interesting that all of your brilliant pontifications include a
derogatory comment about CB'ers. That's odd because I've always
assumed that you are a CB'er or at least own and use a CB radio. Is
that true? Is it possible for you to write something without
mentioning CB or insulting the reader in some manner? Judging by your
past history, I doubt it.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
  #110   Report Post  
Old October 17th 18, 04:12 PM posted to uk.radio.amateur,rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Jun 2007
Posts: 1,332
Default 4NEC2?

On Wed, 17 Oct 2018 10:36:45 +0000, Spike
wrote:
That's the sort of road that Liebermann wanted to take the discussion
down; an interesting topic but not the issue under discussion.


Guilty as charged. I do tend to divert discussions in directions that
I find interesting. After all, why bother writing a long rant that
nobody will read? One-line pontifications, or the all too common
SMS/chat messaging method of discussion are terminally boring, and
rarely produce anything worth reading. The lack of substantiation,
references, and detail found in such short comments offer little in
the way of an education, unless refining one's skill at delivering
insults is considered educational. I've tried to adopt a policy of
only writing and posting things that I think might be worth reading.
That which is unlikely to be of general interest, I don't bother
posting. If everyone followed such a policy, the various newsgroups
would be much more pleasant and interesting to read.

Anyway, I would rant some more, but I'm late for an exercise trudge in
the local state park followed by a lunch meeting with the local hams.
More rants later, if I survive.


--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558


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