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Plans for B&W BWD-65 & BWD-90 Folded Dipole Balun & Terminating Resistor



 
 
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  #1  
Old October 14th 03, 04:19 PM
Dave
Guest
 
Posts: n/a
Default Plans for B&W BWD-65 & BWD-90 Folded Dipole Balun & Terminating Resistor

I'd like to build a replica of the B&W 65 or 90 folded dipole antenna.

I know that there are a lot of arguments against this type of antenna
but for the convienience, I would like to have one anyway.

$220 - $250 seems a bit steep to buy one.

I have read L.B. Cebik's article on Terminated Wideband Dipoles,
http://www.cebik.com/wbfd.html but have been unable to find a source
for the 800-900 ohm resistor or plans for a suitable 16:1 balun.

The only resistors of that value and wattage I have found are
wirewounds which I assume are not suitable because they are inductive.

For an antenna to handle legal limit 1500 watts is it necessary for
the terminating resistor to be 1500 watts? It seems to me that you
would hope that the majority of the power would be dissappated by the
wire and not the resistor.

Does anyone know where I can find a plan for the balun (or a resonably
priced commercially made one)? How about the resistor?

Thanks,

Dave
  #2  
Old October 15th 03, 06:27 AM
Bob Miller
Guest
 
Posts: n/a
Default

On Tue, 14 Oct 2003 11:19:59 -0400, Dave wrote:

I'd like to build a replica of the B&W 65 or 90 folded dipole antenna.



Does anyone know where I can find a plan for the balun (or a resonably
priced commercially made one)? How about the resistor?

Thanks,

Dave


I'm not sure whether you've been to the b&wantennas web site, but they
do sell some or their antenna parts a-la-carte.

Bob
k5qwg

  #3  
Old November 16th 05, 01:46 AM
py8elo py8elo is offline
Junior Member
 
First recorded activity by RadioBanter: Nov 2005
Posts: 5
Smile

Hi Dave,
I believe the resistor should not be inductive and it should have at least 30% of the transmission power therefore, for 1500 Watts it should be of at least 500 Watts.
I build the balun for this antenna (andthe antenna) but I believe in your country is not difficult to acquire it.
I hope it can help you.
VY 73s,
Silva.
PY8ELO

Quote:
Originally Posted by Dave
I'd like to build a replica of the B&W 65 or 90 folded dipole antenna.

I know that there are a lot of arguments against this type of antenna
but for the convienience, I would like to have one anyway.

$220 - $250 seems a bit steep to buy one.

I have read L.B. Cebik's article on Terminated Wideband Dipoles,
http://www.cebik.com/wbfd.html but have been unable to find a source
for the 800-900 ohm resistor or plans for a suitable 16:1 balun.

The only resistors of that value and wattage I have found are
wirewounds which I assume are not suitable because they are inductive.

For an antenna to handle legal limit 1500 watts is it necessary for
the terminating resistor to be 1500 watts? It seems to me that you
would hope that the majority of the power would be dissappated by the
wire and not the resistor.

Does anyone know where I can find a plan for the balun (or a resonably
priced commercially made one)? How about the resistor?

Thanks,

Dave

Last edited by py8elo : November 16th 05 at 01:49 AM.
  #4  
Old November 16th 05, 08:17 PM posted to rec.radio.amateur.antenna
Guest
 
Posts: n/a
Default Plans for B&W BWD-65 & BWD-90 Folded Dipole Balun & TerminatingResistor

Dave;

The only source of resistors and baluns that I have found suitable for
making a B&W antenna is B&W. The terminating resistor is 600 ohms
non-inductive i.e. carbon. The balun is 12 to 1 i.e. 600:50.

If you do find instructions on making the balun please let me know. I
use my B&W BWD-90 daily and it does the job I want it to do. I need
broad band instant QSY for my radio.

Dave WD9BDZ


py8elo wrote:

Hi Dave,
I believe the resistor should not be inductive and it should have at
least 30% of the transmission power therefore, for 1500 Watts it should
be of at least 500 Watts.
I build the balun for this antenna (andthe antenna) but I believe in
your country is not difficult to acquire it.
I hope it can help you.
VY 73s,
Silva.
PY8ELO

Dave Wrote:

I'd like to build a replica of the B&W 65 or 90 folded dipole antenna.

I know that there are a lot of arguments against this type of antenna
but for the convienience, I would like to have one anyway.

$220 - $250 seems a bit steep to buy one.

I have read L.B. Cebik's article on Terminated Wideband Dipoles,
http://www.cebik.com/wbfd.html but have been unable to find a source
for the 800-900 ohm resistor or plans for a suitable 16:1 balun.

The only resistors of that value and wattage I have found are
wirewounds which I assume are not suitable because they are inductive.

For an antenna to handle legal limit 1500 watts is it necessary for
the terminating resistor to be 1500 watts? It seems to me that you
would hope that the majority of the power would be dissappated by the
wire and not the resistor.

Does anyone know where I can find a plan for the balun (or a resonably
priced commercially made one)? How about the resistor?

Thanks,

Dave




  #5  
Old November 16th 05, 10:31 PM posted to rec.radio.amateur.antenna
Guest
 
Posts: n/a
Default Plans for B&W BWD-65 & BWD-90 Folded Dipole Balun & TerminatingResistor

David G. Nagel wrote:
The only source of resistors and baluns that I have found suitable for
making a B&W antenna is B&W.


The terminating resistor is 600 ohms non-inductive i.e. carbon.


I've got about 50 of those 50w suckers in my junk box. They
don't have to be carbon. If one reverses the coil direction
of the resistance wire at mid-point in a wire-wound resistor,
the inductance is minimumized over a certain range of frequencies.
That's what the military often does.
--
73, Cecil http://www.qsl.net/w5dxp
  #6  
Old November 17th 05, 03:10 AM
py8elo py8elo is offline
Junior Member
 
First recorded activity by RadioBanter: Nov 2005
Posts: 5
Thumbs up

Hi Dave,
I use a 1K Ohms resistor and a 16:1 balun. But you can use a 600 Ohms resistor an a 12:1 balun.
I hope it can help you.
Best 73s,
Silva PY8ELO.

Quote:
Originally Posted by David G. Nagel
Dave;

The only source of resistors and baluns that I have found suitable for
making a B&W antenna is B&W. The terminating resistor is 600 ohms
non-inductive i.e. carbon. The balun is 12 to 1 i.e. 600:50.

If you do find instructions on making the balun please let me know. I
use my B&W BWD-90 daily and it does the job I want it to do. I need
broad band instant QSY for my radio.

Dave WD9BDZ


py8elo wrote:

Hi Dave,
I believe the resistor should not be inductive and it should have at
least 30% of the transmission power therefore, for 1500 Watts it should
be of at least 500 Watts.
I build the balun for this antenna (andthe antenna) but I believe in
your country is not difficult to acquire it.
I hope it can help you.
VY 73s,
Silva.
PY8ELO

Dave Wrote:

I'd like to build a replica of the B&W 65 or 90 folded dipole antenna.

I know that there are a lot of arguments against this type of antenna
but for the convienience, I would like to have one anyway.

$220 - $250 seems a bit steep to buy one.

I have read L.B. Cebik's article on Terminated Wideband Dipoles,
http://www.cebik.com/wbfd.html but have been unable to find a source
for the 800-900 ohm resistor or plans for a suitable 16:1 balun.

The only resistors of that value and wattage I have found are
wirewounds which I assume are not suitable because they are inductive.

For an antenna to handle legal limit 1500 watts is it necessary for
the terminating resistor to be 1500 watts? It seems to me that you
would hope that the majority of the power would be dissappated by the
wire and not the resistor.

Does anyone know where I can find a plan for the balun (or a resonably
priced commercially made one)? How about the resistor?

Thanks,

Dave



  #7  
Old November 17th 05, 04:43 AM posted to rec.radio.amateur.antenna
Guest
 
Posts: n/a
Default Plans for B&W BWD-65 & BWD-90 Folded Dipole Balun & TerminatingResistor

Silva;

No reason why your plan should not work. It might require differend
spacing but that is what amateur radios if for: experimentation.
I will give it a try. Where did you get your balun or how did you make
it? Is there a web page showing how?

Dave WD9BDZ


py8elo wrote:

Hi Dave,
I use a 1K Ohms resistor and a 16:1 balun. But you can use a 600 Ohms
resistor an a 12:1 balun.
I hope it can help you.
Best 73s,
Silva PY8ELO.

David G. Nagel Wrote:

Dave;

The only source of resistors and baluns that I have found suitable for
making a B&W antenna is B&W. The terminating resistor is 600 ohms
non-inductive i.e. carbon. The balun is 12 to 1 i.e. 600:50.

If you do find instructions on making the balun please let me know. I
use my B&W BWD-90 daily and it does the job I want it to do. I need
broad band instant QSY for my radio.

Dave WD9BDZ


py8elo wrote:

Hi Dave,
I believe the resistor should not be inductive and it should have at
least 30% of the transmission power therefore, for 1500 Watts it
should
be of at least 500 Watts.
I build the balun for this antenna (andthe antenna) but I believe in
your country is not difficult to acquire it.
I hope it can help you.
VY 73s,
Silva.
PY8ELO

Dave Wrote:

I'd like to build a replica of the B&W 65 or 90 folded dipole antenna.

I know that there are a lot of arguments against this type of antenna
but for the convienience, I would like to have one anyway.

$220 - $250 seems a bit steep to buy one.

I have read L.B. Cebik's article on Terminated Wideband Dipoles,
http://www.cebik.com/wbfd.html but have been unable to find a source
for the 800-900 ohm resistor or plans for a suitable 16:1 balun.

The only resistors of that value and wattage I have found are
wirewounds which I assume are not suitable because they are inductive.

For an antenna to handle legal limit 1500 watts is it necessary for
the terminating resistor to be 1500 watts? It seems to me that you
would hope that the majority of the power would be dissappated by the
wire and not the resistor.

Does anyone know where I can find a plan for the balun (or a resonably
priced commercially made one)? How about the resistor?

Thanks,

Dave






  #8  
Old November 17th 05, 07:47 AM posted to rec.radio.amateur.antenna
Guest
 
Posts: n/a
Default Plans for B&W BWD-65 & BWD-90 Folded Dipole Balun & Terminating Resistor

....i dont know if it still exists but try to hunt for the Moregain
antenna (WATCH the spelling).
another place to look is www.hardcore DX.com . they had material on
the TD2 antenna including formulas for design.
maybe that can help
Saandy 4Z5KS

  #9  
Old November 17th 05, 03:50 PM posted to rec.radio.amateur.antenna
Guest
 
Posts: n/a
Default Plans for B&W BWD-65 & BWD-90 Folded Dipole Balun & TerminatingResistor

If you were to make the load from maybe ten 8.2k 10-20w wire wound
resistors, is the overall inductance really a problem after you parallel
a bunch of them?
Mike


py8elo wrote:
Hi Dave,
I believe the resistor should not be inductive and it should have at
least 30% of the transmission power therefore, for 1500 Watts it should
be of at least 500 Watts.
I build the balun for this antenna (andthe antenna) but I believe in
your country is not difficult to acquire it.
I hope it can help you.
VY 73s,
Silva.
PY8ELO

Dave Wrote:

I'd like to build a replica of the B&W 65 or 90 folded dipole antenna.

I know that there are a lot of arguments against this type of antenna
but for the convienience, I would like to have one anyway.

$220 - $250 seems a bit steep to buy one.

I have read L.B. Cebik's article on Terminated Wideband Dipoles,
http://www.cebik.com/wbfd.html but have been unable to find a source
for the 800-900 ohm resistor or plans for a suitable 16:1 balun.

The only resistors of that value and wattage I have found are
wirewounds which I assume are not suitable because they are inductive.

For an antenna to handle legal limit 1500 watts is it necessary for
the terminating resistor to be 1500 watts? It seems to me that you
would hope that the majority of the power would be dissappated by the
wire and not the resistor.

Does anyone know where I can find a plan for the balun (or a resonably
priced commercially made one)? How about the resistor?

Thanks,

Dave




  #10  
Old November 24th 05, 01:45 AM
py8elo py8elo is offline
Junior Member
 
First recorded activity by RadioBanter: Nov 2005
Posts: 5
Exclamation

Hi Dave,
The resistor is manufactured right here under indent in Brazil,
the balun I build for myself using 8 ferrite beads in material 43 OD = 15mm ID = 8mm...
with each 4 of them I make a tube gluing them and soon after I glue the two tubes forming a binocular core. In it I wind two turns of 16AWG wire and a bifilar wound of 4 turns done with the same wire on the first 2 turns...Of this wound, I joint the begins of a wire in order to the end of the other wire, placing them in against-phase...The extremities that remain will be the high impedance (about 800 Ohms) out to the antenna, them points that were united will join to one of the points of the first wound, which will go to the GND and the point that it remains of the first wound will be the inner of the 50 Ohms coax connector (SO239)... But, it is for low power power... For 1500 Watts you should find the core and the appropriate wire...
I hope it can help you...
Best 73s,
Silva.
PY8ELO
Quote:
Originally Posted by David G. Nagel
Silva;

No reason why your plan should not work. It might require differend
spacing but that is what amateur radios if for: experimentation.
I will give it a try. Where did you get your balun or how did you make
it? Is there a web page showing how?

Dave WD9BDZ


py8elo wrote:

Hi Dave,
I use a 1K Ohms resistor and a 16:1 balun. But you can use a 600 Ohms
resistor an a 12:1 balun.
I hope it can help you.
Best 73s,
Silva PY8ELO.

David G. Nagel Wrote:

Dave;

The only source of resistors and baluns that I have found suitable for
making a B&W antenna is B&W. The terminating resistor is 600 ohms
non-inductive i.e. carbon. The balun is 12 to 1 i.e. 600:50.

If you do find instructions on making the balun please let me know. I
use my B&W BWD-90 daily and it does the job I want it to do. I need
broad band instant QSY for my radio.

Dave WD9BDZ


py8elo wrote:

Hi Dave,
I believe the resistor should not be inductive and it should have at
least 30% of the transmission power therefore, for 1500 Watts it
should
be of at least 500 Watts.
I build the balun for this antenna (andthe antenna) but I believe in
your country is not difficult to acquire it.
I hope it can help you.
VY 73s,
Silva.
PY8ELO

Dave Wrote:

I'd like to build a replica of the B&W 65 or 90 folded dipole antenna.

I know that there are a lot of arguments against this type of antenna
but for the convienience, I would like to have one anyway.

$220 - $250 seems a bit steep to buy one.

I have read L.B. Cebik's article on Terminated Wideband Dipoles,
http://www.cebik.com/wbfd.html but have been unable to find a source
for the 800-900 ohm resistor or plans for a suitable 16:1 balun.

The only resistors of that value and wattage I have found are
wirewounds which I assume are not suitable because they are inductive.

For an antenna to handle legal limit 1500 watts is it necessary for
the terminating resistor to be 1500 watts? It seems to me that you
would hope that the majority of the power would be dissappated by the
wire and not the resistor.

Does anyone know where I can find a plan for the balun (or a resonably
priced commercially made one)? How about the resistor?

Thanks,

Dave





 




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