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  #41   Report Post  
Bruce in Alaska
 
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In article ,
Brian Whatcott wrote:

On Sat, 30 Jul 2005 18:41:54 GMT, Bruce in Alaska
wrote:


Geeze Louise "Me" give the guy a break...... He was just asking for
an opinion....


Bruce in alaska


Hehe...a blow hard is not silenced quite that easily!

:-)

Brian W


Well Brian, it is easy to see that you have never actualy meet "Me"
and really don't know any of the "Players" in Marine Electronics
in, and around the North Pacific.

Bruce in alaska one who does....
--
add a 2 before @
  #42   Report Post  
Me
 
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In article ,
"Mungo Bulge" wrote:

Me is thinking "I'm vindicated" and Chucky is thinking "Another nut
case". You're both right. So why does it work, simple. The antenna isn't
a Marconi; it's an industry standard Marine HF band antenna, 2-30 MHz
bandwidth, 10.8 MHz resonant frequency, 23 feet high and when
connected to an HF radio set configured to its manufacturer's
specifications it will perform admirably. If that were not the case,
we would have had to have had at the very least five quarter wave
Marconi antennae ranging in height from 7.8 to 117 feet and we don't.

That Chucky is the proper use of reductio ad absurdum logic.


Really close Mungo, but the antenna you are talking about doesn't really
have 2-30Mhz Bandwidth, at all. It is a Marconi tuned by an Autotuner,
to make it look like a 50 Ohm load to the radio so that the radio will
transfer as much power as possible to the antenna, minus what is lost in
RF Ground. If the RF Ground impedance is higher than the Antenna
Impedance, with the autotuner doing it's best to make the whole system
appear to the transmitter as 50 Ohms, then most of the RF Energy will
dissipated in the RF Ground and lost to the communicator. Autotuners
suck, when compared to any manual tuner, specifically due to the way the
tuning software has to impliment changes in binary steps, and how the
Phase Detector Sensors provide feedback to the processor while doing a
tuneup. This all plays heavily into the design of the antenna system
connected to the autotuner, as any good tech will put the "Untunable"
1/2 Lambda Frequency in a portion of the spectrum that the user will
NEVER Need to use.

There is a lot of practical considerations that MUST be considered
when designing, and installing MF/HF Marine Radios on any vessel, but
plastic and cellulose hulled vessels make all these things very much
harder to compromise into an Effective Radio Installation.

Me
  #43   Report Post  
Me
 
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In article ,
"Mungo Bulge" wrote:

P.S. The reason I have all this reference material, is that the
Marconi is my "weapon of choice", you see I am a Road Warrior, one of
those sleazy WarDrivers who use laptops equipped with wireless
Ethernet cards and remote antennae to acquire internet access over
unsecured Wireless Access Points. My antenna is a quarter-wave Marconi
with a 30° counterpoise. I use 30° because unlike 45°, the 30°
slopping counterpoise gives a slight upward tilt to the radiation
pattern's maximum lob without affecting impedance that adversely. The
increase in effective radiated power more than cancels the loss due to
reflection and power transfer losses due to impedance mismatch.


You can Wardrive my Wifi Access Points anytime Mungo...... although
they are a bit far away from the civilized world......58N 135W or
therabouts....


Me
  #44   Report Post  
Me
 
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In article ,
Brian Whatcott wrote:

I see that he realises that airborne trailing wire antennas can work
well at HF with just a tube fuselage as a ground reference - miles
away from ground!

This just about completely contradicts his earlier posts about ground
references needing to be in close proximity to the ground for
successful HF work, wouldn't you say?

Brian Whatcott Altus OK


Bzzzt, wrong again...... I never stated that radios with no RF Ground
would never work. I stated that those with a Good RF Grounds, work a
lot better than those that don't.....


Again...."It is the RF Ground, sonny, the RF Ground".....

Me
  #45   Report Post  
Bruce in Alaska
 
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In article ,
"Skip Gundlach on wifi"
skipgundlach.sez.remove.this.part@earthlink.(fish catcher)net wrote:

The inference is, then, that my similarly
equipped VHFs will need some separate antenna? I'd thought they'd connect
to a GPS...


Skip, You inference is likely wrong as most Vhf Radio's with DSC either
use a receive scan function, or a internal, but seperate, Vhf Receiver
to monitor the DSC Vhf Frequency. (Marine Ch 70) While it is impractical
to use that kind of scheme at MF/HF Frequencies because the autotuner
would be set for the last band segment transmitted on, and attenuate the
DSC signals for all the bands except the autotuned band. It is therefor
prefered, that any MF/HF Marine Radio Installation, have a seperate
Receive Only antenna for the DSC Watch Receiver.

Thus the 802's Watch Receiver Antenna requirment.

Bruce in alaska
--
add a 2 before @


  #46   Report Post  
Mungo Bulge
 
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I'll get there again sooner or latter. Maybe on my way back from Lat
69.4 N Long 132.96 W

"Me" wrote in message
...
| In article ,
| "Mungo Bulge" wrote:
|
| P.S. The reason I have all this reference material, is that the
| Marconi is my "weapon of choice", you see I am a Road Warrior, one
of
| those sleazy WarDrivers who use laptops equipped with wireless
| Ethernet cards and remote antennae to acquire internet access over
| unsecured Wireless Access Points. My antenna is a quarter-wave
Marconi
| with a 30° counterpoise. I use 30° because unlike 45°, the 30°
| slopping counterpoise gives a slight upward tilt to the radiation
| pattern's maximum lob without affecting impedance that adversely.
The
| increase in effective radiated power more than cancels the loss
due to
| reflection and power transfer losses due to impedance mismatch.
|
| You can Wardrive my Wifi Access Points anytime Mungo...... although
| they are a bit far away from the civilized world......58N 135W or
| therabouts....
|
|
| Me


  #47   Report Post  
Mungo Bulge
 
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Sorry, I was getting tired. There is one consideration that does need
to be addressed though, and that is ease of use. Not all these
installations will be manned or womanned by honest to goodness radio
operators, or even knowledgeable operators, so for the sake of
operation by neophytes in an emergency when out of range of VHF/UHF an
auto tuner would be one less thing to figure out how to use.
That's just my opinion.
--
The Road Warrior Hobbit

no -- it's NOT ok to contact this account with services or other
commercial interests

"Me" wrote in message
...
| In article ,
| "Mungo Bulge" wrote:
|
| Me is thinking "I'm vindicated" and Chucky is thinking "Another
nut
| case". You're both right. So why does it work, simple. The antenna
isn't
| a Marconi; it's an industry standard Marine HF band antenna, 2-30
MHz
| bandwidth, 10.8 MHz resonant frequency, 23 feet high and when
| connected to an HF radio set configured to its manufacturer's
| specifications it will perform admirably. If that were not the
case,
| we would have had to have had at the very least five quarter wave
| Marconi antennae ranging in height from 7.8 to 117 feet and we
don't.
|
| That Chucky is the proper use of reductio ad absurdum logic.
|
| Really close Mungo, but the antenna you are talking about doesn't
really
| have 2-30Mhz Bandwidth, at all. It is a Marconi tuned by an
Autotuner,
| to make it look like a 50 Ohm load to the radio so that the radio
will
| transfer as much power as possible to the antenna, minus what is
lost in
| RF Ground. If the RF Ground impedance is higher than the Antenna
| Impedance, with the autotuner doing it's best to make the whole
system
| appear to the transmitter as 50 Ohms, then most of the RF Energy
will
| dissipated in the RF Ground and lost to the communicator.
Autotuners
| suck, when compared to any manual tuner, specifically due to the way
the
| tuning software has to impliment changes in binary steps, and how
the
| Phase Detector Sensors provide feedback to the processor while doing
a
| tuneup. This all plays heavily into the design of the antenna
system
| connected to the autotuner, as any good tech will put the
"Untunable"
| 1/2 Lambda Frequency in a portion of the spectrum that the user
will
| NEVER Need to use.
|
| There is a lot of practical considerations that MUST be considered
| when designing, and installing MF/HF Marine Radios on any vessel,
but
| plastic and cellulose hulled vessels make all these things very much
| harder to compromise into an Effective Radio Installation.
|
| Me


  #48   Report Post  
Brian Whatcott
 
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On Mon, 01 Aug 2005 20:23:23 GMT,
the not so anonymous Me wrote:
///
Most compitant folks use both RF Network Analysers

///
Me


Whatever you say, Me....

Actually, I am getting this vast sense of relief, that the big boys
are throwing a little abuse my way. I was feeling *so* left out.

:-)

Brian W
  #49   Report Post  
Brian Whatcott
 
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On Mon, 01 Aug 2005 20:30:19 GMT, Bruce in Alaska
wrote:

////
Well Brian, it is easy to see that you have never actualy meet "Me"
and really don't know any of the "Players" in Marine Electronics
in, and around the North Pacific.

Bruce in alaska one who does....


Oh, I feel such a dud, not even knowing trhat your anonymous buddy is
in fact a big man on the radio waves in Alaska.

Oh, I feel so bad.
Still, I *can* spell. Does that count?
:-)

Brian W

  #50   Report Post  
Me
 
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In article ,
"Mungo Bulge" wrote:

I'll get there again sooner or latter. Maybe on my way back from Lat
69.4 N Long 132.96 W


Over playing with he Canuks, are you? Just make sure you get out befor
the Ice closes in.......


Me
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