Jeff Liebermann wrote:
connection were properly researched and documented. For example, it's
apparent that exposure to low frequency (HF) waves causes a marked
preference for noisy environments, the exact opposite effect is found
after exposure to high frequencies (VHF), where signal clarity is
preferred. This phenomenon and others should be investigated.


Obviously you've never been interested in weak signal V/U/SHF or EME.
These tend to lead to shack environmental noise levels approximating
WWII destroyer engine rooms. Another side effect is hearing CW in wind
noise when driving at over 60mph.

tom
K0TAR

On Wed, 20 May 2009 13:01:07 -0500, Tom Ring
wrote:

Jeff Liebermann wrote:
connection were properly researched and documented. For example, it's
apparent that exposure to low frequency (HF) waves causes a marked
preference for noisy environments, the exact opposite effect is found
after exposure to high frequencies (VHF), where signal clarity is
preferred. This phenomenon and others should be investigated.

Obviously you've never been interested in weak signal V/U/SHF or EME.
These tend to lead to shack environmental noise levels approximating
WWII destroyer engine rooms. Another side effect is hearing CW in wind
noise when driving at over 60mph.

tom
K0TAR

I've done a little of that at VHF frequencies using various digital
modes. I was considering organizing a new certificate for "Worked all
Digital Modes", but every time I add a new mode to my computah,
someone invents yet another digital mode.
http://www.kb9ukd.com/digital/
http://www.wb8nut.com/digital.html
With weak signal digital modes, there's no way to actually hear the
signal as it's well below the noise floor. Waterfall displays work
nicely for copying extremely slow CW. It's a little like modern
astronomy. Most astronomers never look through the eyepiece of a
telescope these days.

Although I'm not a CW operator, when I was into Field Day, it took
several days for me to NOT listen for weak signals under the noise of
conversation, traffic, AM/FM radio noises, etc.

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

Jeff Liebermann wrote:

I've done a little of that at VHF frequencies using various digital
modes. I was considering organizing a new certificate for "Worked all
Digital Modes", but every time I add a new mode to my computah,
someone invents yet another digital mode.
http://www.kb9ukd.com/digital/
http://www.wb8nut.com/digital.html
With weak signal digital modes, there's no way to actually hear the
signal as it's well below the noise floor. Waterfall displays work
nicely for copying extremely slow CW. It's a little like modern
astronomy. Most astronomers never look through the eyepiece of a
telescope these days.

Well, the June VHF QSO Party is in about 3 weeks. Try some non-digital
weak signal. It's fun! I'll be the primary op on our 6m station
running under the club call W0AUS from EN34. No high power this year
since we'll be within LOS of the Twin Cities metro at maybe 300 feet
above local average terrain. We'll be multimulti 6 through 10G,
probably all bands.

I've done some of the digital modes. High speed meteor burst, MFSK, and
PSK31 - really weak stuff with power as low as 50mW back when almost no
one was on it. My personal favorite is Hellschreiber, it's the oldest
(as far as I know) and sounds so cool.


Although I'm not a CW operator, when I was into Field Day, it took
several days for me to NOT listen for weak signals under the noise of
conversation, traffic, AM/FM radio noises, etc.

Yup, after 24 to 40 hours of noise with embedded weak or even not weak
CW and SSB and almost no sleep, you start to hear lots of things.

tom
K0TAR

On May 19, 12:30*pm, Roy Lewallen wrote:
Jeff Liebermann wrote:

Ok. *That's closer than most of the off topic rubbish the pollutes
most newsgroups. *I can see you logic. *After reading some of the
postings in this newsgroup, I too might suspect that exposure to RF
and antennas might produce insanity, illogic, political conservatism,
and delusions of omniscience. . .

The effect seems to peak at about 75 meter wavelength, with a minor peak
at about 2 meters. The cautious and same amateur will avoid exposure to
those wavelengths.

Roy Lewallen, W7EL

Some will probably be skeptical, but I've actually felt the effects
of
RF when operating on the HF bands. I forgot what band it was, but
it was one of the lower ones, "80 or 40", and I was working CW from
my mobile. "parked"
It took a QSO or two before I realized the RF was effecting me.
But I noticed I was starting to feel funny. It's hard to describe the
effects. But I noticed I didn't feel quite right, and it was an
uneasy
queasy type of feeling. Then I started to notice that the feeling
would
subside when I quit transmitting and was listening to the other
station.
When I would go back to transmit, I would slowly start to feel weird
again. I then kind of decided it was the RF hitting me from the rear
of the car, through the window. That particular car was a monte carlo,
and the antenna was on the trunk, with the loading coil fairly low.
So a lot of RF was beaming into the back of my head due to the
location of the antenna. I was running the usual 100w.
So anyway, I don't know about any cancer dilemma, but I know
in some cases, it's possible to feel RF on the HF bands.
Or at least I seemed to..
I didn't like the feeling of it at all. Was not a burning or anything,
it made you feel real nervous and uneasy. Pretty weird.. :/

wrote:
I didn't like the feeling of it at all.

At Texas A&M in the 50's, we had a radar in the
EE building with the antenna on the roof. Once,
someone was working on the antenna when someone
else turned the radar on. They rushed the guy
on the roof to the hospital in an ambulance. I
don't recall the rest of the story.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

As a radio amateur I must be lucky if my neighbours don't
claim headaches and nervous irritation the day after
I put up my new antenna.
Better keep oneself in good shape regarding the arguments.



For real!!

It's jokes like these that catch the attention of superstitious tree huggers
and vegans who wind up protesting by throwing themselves under the bus in
order to promote new legislation.

After more than 30 years as an avid Ham and professional radio tech, NO ONE
I know of in the business or Hams, have suffered from cancer outside of the
occasional Squamous cell skin problems from too much Solar exposure on
building roofs and towers.

wrote:

Some will probably be skeptical, but I've actually felt the effects
of RF when operating on the HF bands. I forgot what band it was, but
it was one of the lower ones, "80 or 40", and I was working CW from
my mobile. "parked"
It took a QSO or two before I realized the RF was effecting me.

I believe you. I have felt the effects of using a cell phone for an
extended time. A warmth sensation. And not the batteries.

What I see as the problem with the whole situation is that there is a
whole spectrum of effects that are tested for. Most are found to be
lacking in evidence. The likelihood of say cell phones as a cause of
cancer is quite low.

In addition, a lot of people who think that RF exposure is terribly bad
are naught but kooks.

But those are not reasons to dismiss any and all effects as nonexistent.

I personally suspect that excessive near field RF exposure at cell phone
frequencies makes people stupid. I used to think it was temporary, but
there has to be a reason for driving while text messaging.

- 73 de Mike N3LI -

Jeff Liebermann wrote:
Was not a burning or anything,
it made you feel real nervous and uneasy. Pretty weird.. :/

Probably if I hadn't had the following experience, I would think you were
kinda loony, Jeff. But I know exactly what you describe.

Several times in my 4th semester in college a good friend and myself would
ditch English class and drive up to Mt. Wilson, the mountain peak above Los
Angeles where almost all of its radio and TV antenna installations are.

There have to be several megawatts of VHF and UHF ERP up there.

Each time we made the trek in his Pinto station wagon, almost as soon as we
rounded the final bend at the top, I would start to feel nauseous. I
couldn't stay up there for more than a few minutes, and for several hours
afterward I would have what I came to call an 'RF headache'-- a dull,
debilitating haze that affected my focus and appetite. I don't know how
anyone who has to work up there does it, having to live in that environment.

Al W6LX

It is likely a bit more complicated than this..

MacaualyFlower wrote:

I know that there is some concern that cell phones may cause cancer.
But is there any possible correlation between the radio waves we use
to communicate, either by commercial radio or other sources and
cancer? Or what about the radio waves that are being emitted from our
personal electronic appliances? I have heard that there is some
concern that if you live near a power line that you may be at risk for
cancer. What is the state of research into this subject?

Thanks

From what I understand, there is a pretty solid set of data now collected that
extended use of cell phones actually does cause high frequency hearing loss!
That from the effects of the RF on the little hairs and the sensors they drive
which let the human hear sounds. I've seen comments that there is now a pretty
much 100% proof that this does happen. Which does make a bit more practical
sense for I suspect most of us here. In the case of cell phone (or equivalent
RF use, such as Blackberry or wireless headset stuff), I think most folks here
could suspect that the VHF frequencies involved would make a lot more practical
sense for this thought than HF and so on...

Of course more than 20 minutes a day of greater than 85DB over room reference
quiet level of any audio sounds, especially the BOOM, BOOM, BOOM of base in
songs and such, also produces permanent hearing loss for the person involved
over time. And with what also goes on in the automobile use for people seems
to include boom box issues as well as cell phone issues for many folks. So one
would also wonder to what extent either of these two motivators for hearing
loss might conflict with research work into such things.


W5WQN

--


-- Sleep well; OS2's still awake!

Mike Luther

On Thu, 21 May 2009 19:29:24 -0700, "Al Lorona"
wrote:

Jeff Liebermann wrote:
Was not a burning or anything,
it made you feel real nervous and uneasy. Pretty weird.. :/

Probably if I hadn't had the following experience, I would think you were
kinda loony, Jeff. But I know exactly what you describe.

Please watch the attributions. I didn't write that quote.

Several times in my 4th semester in college a good friend and myself would
ditch English class and drive up to Mt. Wilson, the mountain peak above Los
Angeles where almost all of its radio and TV antenna installations are.

I spent quite a bit of time up at Mt Wilson in the late 1960's. I
certainly had RF effects, but the causes were obvious. My teeth would
hurt. What was happening was the metal in the fillings was getting
slightly warm. The lousy job the original dentist did left a gap
under the filling, which was full of air, bacteria, crud, whatever.
Heat up the fillings, and the air tries to expand. If it hits the
nerve, my teeth would hurt. This went on for several years until I
had some removed and replaced with the unleaded variety.

I also have a small stainless plate where my skull was fractured while
I was trying to play gang member (at age 14). I eventually outgrew
the plate and had it replaced with a plastic and fake bone version.
The RF induced pains magically went away.

There have to be several megawatts of VHF and UHF ERP up there.

Most of it goes over your head as the antenna patterns are towards the
horizon, not under the towers. Even so, there's still quite a bit
floating around.

I didn't worry much about the RF. It was the falling blocks of ice
when the TV station xmitter baby sitter didn't bother turning on the
de-icer until the VSWR climbed. By then, there was quite a bit of ice
on the antennas. Nothing like big ice blocks falling from 500ft to
ruin my evening. Most went right threw the corregated steel roof on
the commercial radio buildings that sat under the towers. The blocks
didn't do much damage to the radios, which were in racks and boxes.
However, it did a great job of peeling off all the coax cables and
control wires.

Each time we made the trek in his Pinto station wagon, almost as soon as we
rounded the final bend at the top, I would start to feel nauseous.

Probably the fumes from the Pinto. In college, I worked part time for
a local Ford dealer fixing electrical systems in mostly Pintos and
Mavericks. I'd say you were lucky to have made it up the hill.

I
couldn't stay up there for more than a few minutes, and for several hours
afterward I would have what I came to call an 'RF headache'-- a dull,
debilitating haze that affected my focus and appetite. I don't know how
anyone who has to work up there does it, having to live in that environment.

Probably different people have different sensitivity levels. I spent
about 8 days up there helping with a messy install. I never felt
anything exept some altitude sickness (at 5700ft) which affected my
sleep. However, that was in the 1960's, where there were far fewer
xmitters on Mt Wilson. These days, you could probably heat your lunch
by simply waving it in the air.

Al W6LX