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  #111   Report Post  
Old October 17th 18, 04:13 PM posted to uk.radio.amateur,rec.radio.amateur.antenna
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On 17/10/2018 16:00, Jeff Liebermann wrote:
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?


Yes

Do you have the equipment?


Yes

Do you have the knowledge?


Yes

I have
both and believe me, it's often very difficult.


Best deal with someone else who is competent, then.

Today's electronics
is not made to be easily repaired.


Best deal with someone else who is competent, then.

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?


Yes. Send them to me with prepaid return packaging.



After you fail, which
of the above 5 choices would be your next step?


I don't fail, so your question has no meaning.

Or would you just
sell the radio and pretend there was nothing wrong?


That's your train of thought but not mine.


A CBer, probably.


It's interesting that all of your brilliant pontifications include a
derogatory comment about CB'ers.


I don't make derogatory comments about CBers but I do distinguish
the operating hobby which is CB Radio and the whole-life technical
pursuit that is amateur radio. CBers in their own world are harmless
until they try to pass themselves off as radio amateurs.


That's odd because I've always
assumed that you are a CB'er or at least own and use a CB radio.


Your modus operandi is to be rude, which is why you are largely
passed over without even being read.


Is
that true?


I am not in a position to determine that what you said is what you
assumed.


Is it possible for you to write something without
mentioning CB or insulting the reader in some manner?


I do not insult my readership. That is your habit.

Judging by your
past history, I doubt it.


Your habit. QED.



  #112   Report Post  
Old October 17th 18, 06:56 PM posted to uk.radio.amateur,rec.radio.amateur.antenna
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Roger Hayter wrote:
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.


I couldn’t give a **** what you don’t appreciate, Rog. HTH.

Vote Steve!

--
STC / M0TEY /
http://twitter.com/ukradioamateur
  #113   Report Post  
Old October 17th 18, 06:56 PM posted to uk.radio.amateur,rec.radio.amateur.antenna
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Posts: 329
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Jeff Liebermann wrote:
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?


He’s got a track record of not even being able to tune up an FT101 because
his copy of the manual was missing the relevant pages.

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.


Gareth tried CB once but botched the install in his car so badly his signal
couldn’t get even a quarter mile away. It’s all in the archives.

--
STC / M0TEY /
http://twitter.com/ukradioamateur
  #114   Report Post  
Old October 17th 18, 08:44 PM posted to uk.radio.amateur,rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Jun 2018
Posts: 31
Default 4NEC2?

On Wed, 17 Oct 2018, 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.

Except you've built a lot of equipment, and know the theory well. Maybe
you bought one of those fancy rigs that include 50/144/432 so you can go
to a mountaintop so easily and work DX when the band is open. Way more
portable thant equipment from fifty years ago, and it covers all bands
(though maybe not the newer LF bands). Your experimentation is in
following and observing propaganda.

And if you just spent a lot of money on that rig, you might hesitate
because it's small and expensive, rather than because you don't understand
the circuitry,

I know I'm tempted, 46 years after I was licensed, some money I could
spend on it when I've never bought a new rig (or anything much in the way
of used rigs) over the decades. I like the idea of a portable rig, and I
like the idea of it being all bands, because I am way more interested in
VHF and UHF SSB than HF. I know I drooled over the ICOM portables from
the seventies, they had a line that included a 2M FM rig, but also 6M SSB
and 2M SSB, and I think one for 432. Compact and portable and low power.
You can't expect much from an SSB VHF rig unless you're expecting to do
something esoteric with it, like DX or satellite work.

YOu are endlessly trying to set up a classification system that would
never really let many in. The only person I knew that had a COllins rig
was the guy who ran the local code & theory class for decades, who was
very much into the technical end of the hobby and lamented when the rules
changed so the one couldn't build a transmitter with the entry level
license. There's no contradiction, he had his rig and he fixed it when
necessary, but he also build things and kept up with the technical end of
the hobby.

Michael

  #115   Report Post  
Old October 17th 18, 08:54 PM posted to uk.radio.amateur,rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Mar 2017
Posts: 209
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On 17/10/2018 20:44, Michael Black wrote:

YOu are endlessly trying to set up a classification system that would
never really let many in.


Untrue, all those truly self-motivated technically are welcomed.

Amateur radio has privileges to be jealously guarded and is not now,
nor has it ever been, a numbers game to increase bums on seats.




  #116   Report Post  
Old October 17th 18, 08:55 PM posted to uk.radio.amateur,rec.radio.amateur.antenna
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Posts: 43
Default 4NEC2?

On Wed, 17 Oct 2018 08:00:55 -0700, Jeff Liebermann
wrote:

On Wed, 17 Oct 2018 08:48:04 +0100, Gareth's Downstairs Computer
m 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,


Which ones, if you don't mind my asking?
  #117   Report Post  
Old October 18th 18, 01:01 AM posted to uk.radio.amateur,rec.radio.amateur.antenna
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Posts: 1,332
Default 4NEC2?

On Wed, 17 Oct 2018 20:55:22 +0100, Custos Custodum
wrote:

On Wed, 17 Oct 2018 08:00:55 -0700, Jeff Liebermann
wrote:
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,


Which ones, if you don't mind my asking?


I'm now sure what you mean by "which ones" so I'll detail all that I
have in the queue.

1. Astron VS-35m. On arrival, it has all 4 pass transistors blown,
the 723CN regulator blown, two 1N4002 diodes shorted, and a 2N3906
shorted. That left a TIP29 transistor and an MCR225 SCR, which I've
elected to replace instead of test. I don't know what caused all the
damage but I'll confess to blowing up the 723CN regulator by plugging
it into the IC socket backwards.

2. Yet another MJF-259 to repair. I posted a web page on how to fix
these after the input bridge is blown up. It's easy to blow and
doesn't even require a transmitter. You can easily do it with just a
static discharge to the coax connector center pin.
http://www.learnbydestroying.com/jeffl/MFJ-269-repair/
The one I'm trying to repair is an early model and has the usual blown
RF shottky input diodes, with some water damage, leaky battery damage,
and the chronic crappy MFJ soldering on the ribbon cables. Note that
the needed diodes are discontinued and are becoming difficult to find.
I just ordered 100pcs on eBay.

The repair will be easy enough, but the subsequent calibration is a
real time burner. The owner has graciously offered to do the work if
he could do it at my shop as he's lacking in some of the needed test
equipment.
https://www.mfjenterprises.com/MFJ-259Bcalibration.php (not so good)
https://www.w8ji.com/mfj-259b_calibration.htm (more better)

3. There are now three counters in the queue.
One HP5300A counter with HP5302A 50MHz universal counter front end.
Two HP5300B counter with HP5308A 75MHz timer/counter front end
https://picclick.com/HEWLETT-PACKARD-MEASURING-SYSTEM-5300B-HP-50MHz-Universal-123106839896.html
I also have motley assortment of D/A, DC power, and plotter interface.
They all work except the batteries in the DC supply should be
replaced. All the counter sections seem to have the same problems.
There electrolytics in the AC supply show high ESR and all the rotary
switch contacts are tarnished. I just slopped some mineral oil and
oleic acid mix on one of the switches. The contacts look clean and
there are no more bad connections. I'll wash off the acid tomorrow so
that none of the nearby copper becomes corroded. I just ordered some
substitute electrolytics on eBay.

Looking around the shop, there's quite a bit of additional test
equipment that could use my attention. Most of it is not worth the
time but I do it anyway. For example, three sweep generators:
http://www.learnbydestroying.com/jeffl/pics/home/slides/BL-shop5.html
There also a bunch of big linear power supplies that probably need new
electrolytics. My IFR-1500 has a blown power supply that I can't seem
to fix. I thought I had it fixed in 2010, but it died again in 2015:
http://www.learnbydestroying.com/jeffl/IFR-1500%20Power%20Supply%20Repair/IFR-1500%20power%20supply%20repair.html

Does that answer your question?

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
  #118   Report Post  
Old October 18th 18, 02:35 AM posted to uk.radio.amateur,rec.radio.amateur.antenna
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Posts: 1,332
Default 4NEC2?

On Wed, 17 Oct 2018 14:32:20 +0000, Spike
wrote:
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.


I guess it's too late to put you back into your box. Yes, I'm one of
those rules-n-regs types. I've even been involved in manufacturing a
few standards. Since you have an open mind, I hope you don't mind if
I pour some reasons why we have rules-n-regs into your wide open mind.

In order to talk with someone via radio, you don't really need rules.
You could simply build or buy something that generates and detects RF,
attach a modulator, and now you're talking. The necessary ingredients
are commonly available and fairly inexpensive. Not much more than a
frequency counter or frequency standard are required so that you and
your accomplice are both on the same frequency. Tuning with a light
bulb is perfectly functional and will probably help with the tuning.

However, there's a problem. You and your accomplice are not the only
people on the air. There are others that also want to communicate
with their friends and find that spurious crap belched by badly
designed, badly constructed, or mis-adjusted transmitters are making
their communications rather difficult. Similarly, your ability to
receive transmissions from your accomplice might be limited by the
spurious junk produced by the other users of the spectrum. Therefore,
it would helpful if your receiver was somewhat tolerant to intermod,
overload, blocking, adjacent channel, spurious responses, and other
anomalies.

In order to insure a minimum level of quality, the various regulatory
agencies produce specifications and testing procedures. In other
words, they produce numbers. Manufacturers and builders of radios are
expected to test their products to those standards and fix anything
that fails to comply. If everyone complies, then there's a good
chance that you and your accomplice will be able to communicate
without either transmitting or receiving any interference.

Like you, I once had an open mind when it came to radio regulations.
At the time, I was designing marine VHF FM radios. I was faced with a
blocking (receiver overload) specification that was almost impossible.
The interfering signal was so high that my test equipment could not
produce the level required. I calculated that the interfering station
antenna would need to be about 2 ft (60 cm) from my radio antenna to
produce the required interference level. My open mind declared that
to be ridiculous. I protested the specification and waited. In the
return mail (this was before email), I received several photos of
typical marine masts, yardarms, and towers, showing dual watch VHF
antennas about 2ft away from each other. Oops. It was a real problem
that required the radio to meet the specification.

Obviously, all these specifications ultimately manifest themselves in
the form or numbers. You'll find them all over the various FCC and
Ofcom rules-n-regs. They're there to insure that you, your
accomplice, and other users can communicate without mutual
interference. There is no other way to insure reliable communications
without measurements and test equipment.

So, how do you make an RF tuning light bulb produce numbers? A light
meter?


--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
  #119   Report Post  
Old October 18th 18, 09:09 AM posted to uk.radio.amateur,rec.radio.amateur.antenna
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Posts: 180
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On 18/10/2018 01:35, Jeff Liebermann wrote:
On Wed, 17 Oct 2018 14:32:20 +0000, Spike
wrote:


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.


I guess it's too late to put you back into your box. Yes, I'm one of
those rules-n-regs types. I've even been involved in manufacturing a
few standards. Since you have an open mind, I hope you don't mind if
I pour some reasons why we have rules-n-regs into your wide open mind.


diversion into a side-topic snipped

So, how do you make an RF tuning light bulb produce numbers? A light
meter?


By calculation, old boy, by calculation. Don't you do calculations in
the US?


--
Spike

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

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Old October 18th 18, 02:32 PM posted to uk.radio.amateur,rec.radio.amateur.antenna
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Posts: 43
Default 4NEC2?

On Wed, 17 Oct 2018 17:01:33 -0700, Jeff Liebermann
wrote:

On Wed, 17 Oct 2018 20:55:22 +0100, Custos Custodum
wrote:

On Wed, 17 Oct 2018 08:00:55 -0700, Jeff Liebermann
wrote:
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,


Which ones, if you don't mind my asking?


I'm now sure what you mean by "which ones" so I'll detail all that I
have in the queue.

1. Astron VS-35m. On arrival, it has all 4 pass transistors blown,
the 723CN regulator blown, two 1N4002 diodes shorted, and a 2N3906
shorted. That left a TIP29 transistor and an MCR225 SCR, which I've
elected to replace instead of test. I don't know what caused all the
damage but I'll confess to blowing up the 723CN regulator by plugging
it into the IC socket backwards.

2. Yet another MJF-259 to repair. I posted a web page on how to fix
these after the input bridge is blown up. It's easy to blow and
doesn't even require a transmitter. You can easily do it with just a
static discharge to the coax connector center pin.
http://www.learnbydestroying.com/jeffl/MFJ-269-repair/
The one I'm trying to repair is an early model and has the usual blown
RF shottky input diodes, with some water damage, leaky battery damage,
and the chronic crappy MFJ soldering on the ribbon cables. Note that
the needed diodes are discontinued and are becoming difficult to find.
I just ordered 100pcs on eBay.

The repair will be easy enough, but the subsequent calibration is a
real time burner. The owner has graciously offered to do the work if
he could do it at my shop as he's lacking in some of the needed test
equipment.
https://www.mfjenterprises.com/MFJ-259Bcalibration.php (not so good)
https://www.w8ji.com/mfj-259b_calibration.htm (more better)

3. There are now three counters in the queue.
One HP5300A counter with HP5302A 50MHz universal counter front end.
Two HP5300B counter with HP5308A 75MHz timer/counter front end
https://picclick.com/HEWLETT-PACKARD-MEASURING-SYSTEM-5300B-HP-50MHz-Universal-123106839896.html
I also have motley assortment of D/A, DC power, and plotter interface.
They all work except the batteries in the DC supply should be
replaced. All the counter sections seem to have the same problems.
There electrolytics in the AC supply show high ESR and all the rotary
switch contacts are tarnished. I just slopped some mineral oil and
oleic acid mix on one of the switches. The contacts look clean and
there are no more bad connections. I'll wash off the acid tomorrow so
that none of the nearby copper becomes corroded. I just ordered some
substitute electrolytics on eBay.

Looking around the shop, there's quite a bit of additional test
equipment that could use my attention. Most of it is not worth the
time but I do it anyway. For example, three sweep generators:
http://www.learnbydestroying.com/jeffl/pics/home/slides/BL-shop5.html
There also a bunch of big linear power supplies that probably need new
electrolytics. My IFR-1500 has a blown power supply that I can't seem
to fix. I thought I had it fixed in 2010, but it died again in 2015:
http://www.learnbydestroying.com/jeffl/IFR-1500%20Power%20Supply%20Repair/IFR-1500%20power%20supply%20repair.html

Does that answer your question?


Yes, thanks. I was curious about the counters as I have some
post-design experience of some of the later models in that range, but
yours were a bit before my time (mid-70s, IIRC). I might have been
able to help you out with hard-to-get parts.


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