On Thu, 26 Apr 2007 22:46:54 -0500, Vic Smith
wrote:

Hi Vic,
Thanks for this tip that I had forgotten. I had expected an irate
outburst from you denying that you were a coffee philistine but you
ignored the bait.

Years ago when we used to go camping (tenting) as a young family at
our beach property we used this trick to keep fhe food cool. We had no
spare cash to buy a fridge and would hang such as milk bottles (are
you old enough to remember when milk came in bottles?) wrapped in a
wet rag from a shaded tree branch. The evaporation kept it cool. I
also had a couple of open sided large concrete building blocks (8
inches wide ones to give a 16 inch square) buried in the sandy ground
- 2 high with a concrete paving stone on top. It also was in the shade
and kept constantly damp. Both worked very well.

I taught science at highschool for a couple of years then and am
trying to remember the science of it. Something about the latent heat
of evaporation and the energy required to turn the water into a gas
and why methylated spirits or alcohol rubbed on the skin gives a
greater cooling feeling than does water. It turns into a gas at a
lower temperature. Memory is dim on this.

I understand your memories of having coffee at some of the places you
must have visited in the Med. My family being from Crete, I was raised
on the Greek/Turkish style of heating it on a sand brazier in a small
pot which I sometimes drink on the boat though I do prefer Italian
style espresso. Unfortunately I don't have the power for a decent
expresso machine onboard though I have one at home.

My best coffee memory is of rising at 5 am in the hotel in Cairo (I am
an early riser) and going to a 24 hour cafe to have coffee and a
shisha (huba buba water filtered smoking device) in the street with
other regulars on their way to and from work. Same as you, probably
the ambiance.

I agree. There is nothing quite like a cold coke when you are thirsty
and hot. Must be the caffiene hit and thus the resultant addiction.
Damned economic imperialism. It should be included in the war on
drugs.

Incidentally, as to our term 'philistine', it appears that it is a
misnomer and that it was the Israelites who were the unsophisticated
tribal barbarians who had migrated in from the desert and who were the
destroyers. The Israeli archeological department and academics have
recently excavated many Philistine cities and have expressed this view
themselves. They have shown that the Philistines were from Mycenean
Greece and were the kin of Agamemnon, Menelaus, Ulysses, and Achilles
(who was of course my direct ancestor on my mother's father's side of
the family). They had a very definite high level of sophisticated
manufacture of bronze, gold and pottery and also used traded goods
from all over the known world, being maritime merchants themselves
which is why these cities were founded along the coast.

Before I get castigated for being anti-Israeli (I'm not) by those who
make an overly simple connection, look it up on the web. I am
fascinated by the proven connection they have made with the many
references in historical literature throughout the Middle East to the
"sea peoples". It was always a mystery as to who they were and where
they came from.

If you are interested, also look up the 14th century BC bronze age
shipwreck that is now displayed in the museum at Bodrum castle in
Turkey. It contains items from all over the then known world and shows
the well developed trade links between nations. Bronze, wine and olive
oil were the base products for international commerce then, not
Coca-Cola.

Yes, I know that this is off topic, but this is why I 'cruise' - to
visit these places and see and experience in the first person. My
occupation is in modern technology but my passion is for history.

cheers
Peter

Our method of cooling a can of soda in the boiler room was to wrap it
in a wet rag and place it in a vent. The strength of the air blowing
there was very strong. Maybe 30 knots. The rag was wetted as many
times as necessary to cool the soda. Repeated wetting only whetted
the appetite for the imminent treat.
Can't say exactly how cold it got the soda, but I'd estimate 70
degrees or less. Damn cold relatively speaking.
And in the case of cooling Coke in a Navy boiler room, I am a
relativist.
Whether this would work for tropical sailors I don't know.

--Vic

On Fri, 27 Apr 2007 05:54:45 -0400, Peter Hendra
wrote:

On Thu, 26 Apr 2007 22:46:54 -0500, Vic Smith
wrote:

Hi Vic,
Thanks for this tip that I had forgotten. I had expected an irate
outburst from you denying that you were a coffee philistine but you
ignored the bait.

Ah. Then you are prone to making unfounded assumptions.
I must say I am disappointed at that (-:

Years ago when we used to go camping (tenting) as a young family at
our beach property we used this trick to keep fhe food cool. We had no
spare cash to buy a fridge and would hang such as milk bottles (are
you old enough to remember when milk came in bottles?)

Yes, and with cream floating on top too. And I remember scraping wax
with my fingernails from coated cardboard milk cartons as I ate
cereal, when that transition was made. They say more changes in the
way we live have occurred in the last 100 or so years than in all
times prior. I've seen many of those changes myself, recalling living
with an icebox, horse drawn vendor wagons in the streets of Chicago,
etc. But here's something pasted below that I noted in another group
a while ago. It was a thread about "most important innovations."
It puts technological progress in a perspective we normally don't - or
can't - imagine.
"An old farmer I saw on the Johnny Carson had his answer, which with I
agree, and from the response of the audience, they did too.
He was 100 years old, and Carson asked him if he was still working the
farm. He said he did a bit of work, but his son was doing the
seeding, plowing, etc. Carson asked him how old is your son, and
the farmer said 80. That got a laugh.
Then - this was very early '70s - Carson mentioned TV, man on the
moon, fast cars, etc, all the usual suspect innovations you might
imagine that a man born about 1870 and still alive had witnessed.
Then Carson asked the old guy what innovation had most impressed him
and changed his life during its long span.
The old man didn't bat an eye, but just said "Electricity."
The audience roared.
Nobody expected that answer, because they took that for granted.
But judging from Carson's and the audience's reaction, nobody
disagreed."

wrapped in a
wet rag from a shaded tree branch. The evaporation kept it cool. I
also had a couple of open sided large concrete building blocks (8
inches wide ones to give a 16 inch square) buried in the sandy ground
- 2 high with a concrete paving stone on top. It also was in the shade
and kept constantly damp. Both worked very well.

I taught science at highschool for a couple of years then and am
trying to remember the science of it. Something about the latent heat
of evaporation and the energy required to turn the water into a gas
and why methylated spirits or alcohol rubbed on the skin gives a
greater cooling feeling than does water. It turns into a gas at a
lower temperature. Memory is dim on this.

Sounds right enough. My steam training covered all this and I used to
hold in my head the BTU count for every stage of the water to steam
process. Vaporization is by far the most energetic piece, and did the
trick with a can of Coke.

I understand your memories of having coffee at some of the places you
must have visited in the Med. My family being from Crete, I was raised
on the Greek/Turkish style of heating it on a sand brazier in a small
pot which I sometimes drink on the boat though I do prefer Italian
style espresso. Unfortunately I don't have the power for a decent
expresso machine onboard though I have one at home.

Your family being from Crete perhaps gives you a special sensitivity
to words such as "philistine."
Actually, I haven't had an espresso coffee since Italy many years ago.
They were mostly con leche or con cognac.
I did learn a pidgin Italiano and those Spanish terms sufficed for my
infrequent coffee orders in Italy.
My habits are at least half a gallon on coffee daily and coffee is my
main source of liquids. Espresso would quickly do me in, all else
being equal.
I do occasionally make a very strong drip brew but it is weaker than
espresso. I am about to go out with my wife and am determined to stop
for an espresso to erase my current ignorance..

My best coffee memory is of rising at 5 am in the hotel in Cairo (I am
an early riser) and going to a 24 hour cafe to have coffee and a
shisha (huba buba water filtered smoking device) in the street with
other regulars on their way to and from work. Same as you, probably
the ambiance.

I agree. There is nothing quite like a cold coke when you are thirsty
and hot. Must be the caffiene hit and thus the resultant addiction.
Damned economic imperialism. It should be included in the war on
drugs.

Exactly right about thirsty and hot. That is really the main time I
drink it. And addiction. I was surprised when my otherwise food-
frugal wife got the habit of a Coke every day. She's originally a
farm girl from Poland and wasn't exposed to it there.
Better that than vodka, no doubt.

Incidentally, as to our term 'philistine', it appears that it is a
misnomer and that it was the Israelites who were the unsophisticated
tribal barbarians who had migrated in from the desert and who were the
destroyers. The Israeli archeological department and academics have
recently excavated many Philistine cities and have expressed this view
themselves. They have shown that the Philistines were from Mycenean
Greece and were the kin of Agamemnon, Menelaus, Ulysses, and Achilles
(who was of course my direct ancestor on my mother's father's side of
the family). They had a very definite high level of sophisticated
manufacture of bronze, gold and pottery and also used traded goods
from all over the known world, being maritime merchants themselves
which is why these cities were founded along the coast.

Before I get castigated for being anti-Israeli (I'm not) by those who
make an overly simple connection, look it up on the web. I am
fascinated by the proven connection they have made with the many
references in historical literature throughout the Middle East to the
"sea peoples". It was always a mystery as to who they were and where
they came from.

If you are interested, also look up the 14th century BC bronze age
shipwreck that is now displayed in the museum at Bodrum castle in
Turkey. It contains items from all over the then known world and shows
the well developed trade links between nations. Bronze, wine and olive
oil were the base products for international commerce then, not
Coca-Cola.

What a rich find that was! And it must have been a great loss to
merchants of the time when it sank. I wish I knew of this when
my destroyer was steaming about Cyprus in 1964 during that
so-called "crisis." It would have added some reflection to that
boring time, when we were at sea for more than 30 days.
I'm also interested in history and cultures, and sensing the place
in time of events can be an almost mystical experience.
In 1988 I took my family on a driving trip of the western U.S.
We mostly stayed off the interstate highways and tent camped
except every 5th day or so, when we would overnight in a motel.
We stopped at many historical sites, mostly related to the westward
settlement of America; wagon trails, sites of Indian ambushes, etc.
Most of these were very recent in the scope of time, circa mid-19th
century.
One day in a small Kansas town we stopped in the town museum.
I can't recall the name of the town.
I saw a metal helmet in a glass case, and upon reading the description
found it was discovered by a boy in a cave outside town in 1912 and
experts say it was left there by a member of Coronado's expedition of
1540! Since I have studied some history and literature I instantly
had a context for this as immediately predating Shakespeare and
the Elizabethan period. I stood in awe before that helmet, with
thoughts of the Spanish Conquests, gold, Coronado, Aztecs, native
American Indian cultures, Henry VIII, his wives, English law, the
Jamestown settlement 67 years in the future of this helmet's placement
in the lonely Kansas cave - all flying about in my head. It was one
of those subliminal experiences.
In writing this I did a net search to find the name of that Kansas
town and discovered the provenance of artifacts like this helmet
are somewhat in question, and it is likely I was simply a tourist rube
tricked by some slick Kansas chamber of commerce scheme.
Be that as it may, Coronado was close by in 1540 and that helmet
did the trick for me in putting this Kansas place in the vast sweep
of time. BTW, Dana's Two Years Before the Mast had a similar effect
on me when I read of that 1834 voyage knowing of other contemporary
events.
My history knowledge is lacking many specifics in many areas not
directly studied in college, largely due to my lack of travel. When I
traveled to Europe and the Caribbean as a youth I had more interest in
whorestory than history. But of course that was also something of a
cultural education and more fun to me at that time than stuffy
museums.

Yes, I know that this is off topic, but this is why I 'cruise' - to
visit these places and see and experience in the first person. My
occupation is in modern technology but my passion is for history.

Very good. Wish I were with you drinking coffee.

--Vic

Peter Hendra wrote in
:

Could I
attach a cable to that and throwm it ovewr the stern? - or would two
attached to the capshrouds give better protection? I unashamdely admit
to being terrified of being struck again - not a personal fear but one
of having to shell out all those dollars again to replace it all.


Yes, that should work fine as a good static discharge if the solid
backstay is electrically attached to the metal mast. The more paths you
provide to seawater ground from that mast....smooth paths with no hard
angles just to make it look "neat", whatever that means....the better.

There is no such thing as "lightning protection". There is surge
protection and static discharge. Static discharge helps prevent
lightning strikes on anything. The static radiating off things is what
makes the path for the "main bang", hundreds of millions of amps at
hundreds of millions of volts nothing can possibly stop.

If your boat is directly hit by a massive lightning strike, it will be
destroyed, not an issue. However, oddly, not many direct hits happen.
What does happen is static discharges from nearby hits and St Elmo's
Fire, the buildup of static on the rigging not bled off. These
discharges, say from the base of an ungrounded mast, will hole the hull
in a hundred places...sinking the boat.

One of my friends was senior engineer for Dialpage in Charleston. I had
a packet 2 meter ham radio digital station on one of Dailpage's towers,
serving the ham community with packet radio for years.

This tower had 3 candelabra-mounted paging antennas at 330 ft AGL and a
very nice grounding system to bleed off the static charge, done the best
way possible to protect the expensive paging transmitters.

It took a direct hit. The top 8 ft of the tower, along with the entire
candelabra antenna system, SIMPLY VANISHED. Not a trace of it was found
on the ground. The stroke mostly ignored the extensive, professionally-
installed ground system after the stroke turned bridge cables into molten
bits of metal, all the way to bedrock under the tower. After those first
few microseconds, now with no ground system, the stroke entered the
transmitter building, which also had a very extensive, professionally-
installed grounding system to protect everything in the building. Bus
bars that were 1/2" thick copper by 2" wide straps were melted, ripped
out of their mounting brackets by the intense magnetic pulse (EMP) the
stroke caused. Every piece of paging equipment, tower lighting
equipment, emergency and AC power panels, even the big diesel genset
outside on its pad, were utterly destroyed. The huge power cables that
came from the building to the power pole outside were "stretched" by the
current blast that blew the transformers (3 phases) off the pole and
drooped these heavy cables to within a foot of the road they crossed
over.

A boater stands NO chance against such a stroke. Glad it doesn't happen
often, but I cannot imagine why.

WJBF-TV/FM in Augusta, GA, was similarly destroyed by a direct hit a long
time ago. The stroke destroyed the telephone system around the tower
over a diameter of over 4 miles! JBF is Channel 6. A few miles away is
Channel 12's tower...the OTHER part of the path! The stroke hit them
both in a big, grounded loop, simultaneously. One of my old broadcast
buddies, who was the duty engineer at JBF at the time, weighted in around
400 pounds. It blew him right off his chair at the console! The stroke
came out the front panel of the FM transmitter and hit the console he was
sitting at! He came to in time to help put out the fires and get out of
the building. They were off the air for months replacing it
all...melted.

Larry
--
Lightning scares the crap out of me, sitting there in the cockpit at the
base of the big lightning rods, holding onto the metal wheel hooked to
the metal GROUNDED rudder hanging out in the sea, below.....

Peter Hendra wrote in
:

Oh, and what is an optimum length and diameter - covered in plastic or
bare? - I know, only a project manager would want precision such as
this.

Thanks for all of this Larry. I shall follow your advice.



Optimum length would be 5% longer than 1/4 wavelength of the frequency
you are operating on. 1/4 wavelength in meters is 75.7/frequency in Mhz.

So, if we are on 6 Mhz, for instance, we get 75.7/6 x 1.05 = 13.2 meters.

But, because the radiating element ISN'T a proper length and we are using
a tuner, just make it LONG and the tuner will tune out the reactance and
match it up...

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

On another issue you have brought up, you said you had two backstays in
parallel, one with insulators that is the antenna and one that is not and
is solidly connected to the mast, right??

If this is so, in close proximity to the radiating element, that second
backstay is simply absorbing a major part of your radiation from the real
antenna, greatly reducing your actual field strength at some remote
receiver. We can't stop induced, out of phase, RF currents in any of the
rigging, but you can reduce it, greatly, giving you a nicely stronger
signal.

If these backstays are as I think, please consider putting insulators at
equal distance in BOTH backstays,not just one. Then, run a jumper
between upper end of the bottom insulators, effectively paralleling them.
Feed the tuner into the CENTER of this jumper, which can also be two
equal-length wires from the HV output of the tuner to the two insulator
feedpoints. The effect of doing this is a radiator that is MUCH greater
in "virtual diameter", both radiating IN PHASE, which aids their field
strength. Instead of the second backstay absorbing the signal, it will
create more signal, in phase. If your tuner is below them, you can
either make a T to feed the two backstays or just Y them out of the
tuner, itself, with EQUAL LENGTH conductors to preserve their phase
relationship.

Larry
--
Antennas R Us
If it doesn't glow blue after dark, power output is down.....(c;

On Fri, 27 Apr 2007 09:23:57 -0500, Vic Smith
wrote:

The old man didn't bat an eye, but just said "Electricity."
The audience roared.
Nobody expected that answer, because they took that for granted.
But judging from Carson's and the audience's reaction, nobody
disagreed."

Just spend a few days in your house without electricity and you will
rapidly agree. It changes your whole lifestyle, and not for the
better.

....
Lightning scares the crap out of me, sitting there in the cockpit at the
base of the big lightning rods, holding onto the metal wheel hooked to
the metal GROUNDED rudder hanging out in the sea, below.....

Me too. It is certainly the scariest thing we see regularly when off
shore. I routinely run a chain from my forestay to the sea (you can
do this on a catamaran) in the hope that it will direct the worst of a
hit away from the people on the boat. But, when I look at the
aluminum mast full of copper wires all nicely grounded to my engines
that are electrically connected to the sea I have doubts about how
much current will decide to go down a stainless wire. Do you think
that the resistance is small enough on stainless wire to dissipate the
static charge, or would it be better to ground the mast to the sea
with a low resistance wire to deal with the static?

-- Tom.

" wrote in
ps.com:

Do you think
that the resistance is small enough on stainless wire to dissipate the
static charge, or would it be better to ground the mast to the sea
with a low resistance wire to deal with the static?


Static, yes. NOTHING dissipates lightning's pulse.

http://www.youtube.com/watch?v=djZo0...elated&search=
Watch his hand arc to the insulated-from-ground motorcycle! EMP caused the
bike to be instantly charged.

http://www.youtube.com/watch?v=lUUOd...elated&search=
Direct hit on a minivan on the road!

http://www.youtube.com/watch?v=bNhY3...elated&search=
This one hitting a tower would be what your boat mast would look like....

Larry
--

Thanks Larry,
You are making my simple mind spin.

Seriously though, I am truly appreciative of your advice in this and
all matters. What you say about backstay aerials makes sense and I
shall do as you suggest. What I would really like, as do most others,
is long range voice comms. If anything reasonable helps in any way, I
will do it. There is nothing quite so annoying as to not be able to
receive an interpretable weather fax because of poor reception.

I'll add the ground from my stays. By the way, I neglected to tell
that I have a painted box section wooden mast, deck stepped. Forestay,
backstays and capshrouds are electrically connected due to their
attachment at the head of the mast. There is an aluminium sailtrack
which has no connection. Should this be a factor for consideration?

My specific area of small expertise over the past few years has been
packet data and such as better compression algorithms, up and down
linking to comms satellites, and the problem of latency or delay in
resending packets - solved by a really neat way of transmitting two
packet streams, with a slight delay on the second. If one packet
address is missing or denatured in some way, "it" merely grabs its
copy from the second incoming stream without having to ask the
originator for a resend and the consequent latency or time delays
whilst waiting - speeds it up no end. Probably been invented before
somewhere else but that sort of thing happens all the time. The
tracking system can track all of our active patrol boats as well as
Indonesia's ( and give postion, direction, speed and a lot of other
data in sub minute real time as well as sending and receiving text
messages and orders. If we needed to, we could add engine revs,
temperature and a lot of other really uinnecessary stuff.

Even though mobile phones are just glorified two channel radios, So
far as radio propagation (and most of the rest of it) has failed to
lodge in my brain successfully.

Thanks again for being so helpful and for freely disseminating your
experienced advice to those such as me whom you will probably never
meet.

cheers
Peter

On Fri, 27 Apr 2007 16:33:31 +0000, Larry wrote:

Peter Hendra wrote in
:

Oh, and what is an optimum length and diameter - covered in plastic or
bare? - I know, only a project manager would want precision such as
this.

Thanks for all of this Larry. I shall follow your advice.



Optimum length would be 5% longer than 1/4 wavelength of the frequency
you are operating on. 1/4 wavelength in meters is 75.7/frequency in Mhz.

So, if we are on 6 Mhz, for instance, we get 75.7/6 x 1.05 = 13.2 meters.

But, because the radiating element ISN'T a proper length and we are using
a tuner, just make it LONG and the tuner will tune out the reactance and
match it up...

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

On another issue you have brought up, you said you had two backstays in
parallel, one with insulators that is the antenna and one that is not and
is solidly connected to the mast, right??

If this is so, in close proximity to the radiating element, that second
backstay is simply absorbing a major part of your radiation from the real
antenna, greatly reducing your actual field strength at some remote
receiver. We can't stop induced, out of phase, RF currents in any of the
rigging, but you can reduce it, greatly, giving you a nicely stronger
signal.

If these backstays are as I think, please consider putting insulators at
equal distance in BOTH backstays,not just one. Then, run a jumper
between upper end of the bottom insulators, effectively paralleling them.
Feed the tuner into the CENTER of this jumper, which can also be two
equal-length wires from the HV output of the tuner to the two insulator
feedpoints. The effect of doing this is a radiator that is MUCH greater
in "virtual diameter", both radiating IN PHASE, which aids their field
strength. Instead of the second backstay absorbing the signal, it will
create more signal, in phase. If your tuner is below them, you can
either make a T to feed the two backstays or just Y them out of the
tuner, itself, with EQUAL LENGTH conductors to preserve their phase
relationship.

Larry

On Fri, 27 Apr 2007 16:33:31 +0000, Larry wrote:

Hi Larry,

On another issue you have brought up, you said you had two backstays in
parallel, one with insulators that is the antenna and one that is not and
is solidly connected to the mast, right??

Correct. as advised by a rigger who was using a rule of thumb, the top
insulator is 3 feet down from the seperation point.

If this is so, in close proximity to the radiating element, that second
backstay is simply absorbing a major part of your radiation from the real
antenna, greatly reducing your actual field strength at some remote
receiver. We can't stop induced, out of phase, RF currents in any of the
rigging, but you can reduce it, greatly, giving you a nicely stronger
signal.

If these backstays are as I think, please consider putting insulators at
equal distance in BOTH backstays,not just one. Then, run a jumper
between upper end of the bottom insulators, effectively paralleling them.
Feed the tuner into the CENTER of this jumper, which can also be two
equal-length wires from the HV output of the tuner to the two insulator
feedpoints. The effect of doing this is a radiator that is MUCH greater
in "virtual diameter", both radiating IN PHASE, which aids their field
strength. Instead of the second backstay absorbing the signal, it will
create more signal, in phase. If your tuner is below them, you can
either make a T to feed the two backstays or just Y them out of the
tuner, itself, with EQUAL LENGTH conductors to preserve their phase
relationship.

Larry

On Sat, 28 Apr 2007 02:40:19 +0000, Larry wrote:

" wrote in
ups.com:

Do you think
that the resistance is small enough on stainless wire to dissipate the
static charge, or would it be better to ground the mast to the sea
with a low resistance wire to deal with the static?


Static, yes. NOTHING dissipates lightning's pulse.

http://www.youtube.com/watch?v=djZo0...elated&search=
Watch his hand arc to the insulated-from-ground motorcycle! EMP caused the
bike to be instantly charged.

http://www.youtube.com/watch?v=lUUOd...elated&search=
Direct hit on a minivan on the road!

http://www.youtube.com/watch?v=bNhY3...elated&search=
This one hitting a tower would be what your boat mast would look like....

Larry

Wow Larry!
I think I'll walk back home a liitleways behind my wife who will have
an open umbrella. You are quite right. There is nothing so numbing to
one's sense of well being than to be on a yacht that is the highest
thing around with lightning hitting the sea around you. It is a
horrible feeling of just waiting and knowing inside your soul that it
will probably happen soon. It's quite amazing what it does to a
normally rational mind. Does sacrificing chickens help in anyway? I
could carry a cage over the stern. So, if Zeus is angry at us Greeks
for neglecting to worship him for the past 1700 years or so, we could
appease him with a little chicken? Or, should I aquire a bronze tripod
and brazier and offer hecatombs of fat ox flesh in a fire?

My wife's people (Maori's) in New Zealand always throw back the first
fish (no matter how big or even if they have caught nothing for hours)
caught as an offering to the sea god Tangaroa even though they are
Christian, as educated as anyone else and don't believe in the old
god's. When there, I even do it. Scratch modern man and the primitive
is only beneath the skin. You just never know.

So, how about chickens?

cheers
Peter