Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Old September 30th 05, 01:29 PM
Lee
 
Posts: n/a
Default Magnetic Loop !!!

Hi !!.

I`ve just built a magnetic loop for 20m, it is 1 metre circumference and
uses a coaxial capacitor (RG58... QRP operation!!!) , it receives very
well but doesn`t transmit very well at all !!!!.....it loads but T/X isn`t
up
to R/X.....

Any advice will be greatly appreciated.....

Thanks....

Lee....G6ZSG....




  #2   Report Post  
Old September 30th 05, 01:59 PM
Reg Edwards
 
Posts: n/a
Default

I`ve just built a magnetic loop for 20m, it is 1 metre circumference
and
uses a coaxial capacitor (RG58... QRP operation!!!) , it receives

very
well but doesn`t transmit very well at all !!!!.....it loads but

T/X isn`t
up
to R/X.....

Any advice will be greatly appreciated.....

==============================
There's almost certainly nothing the matter with it.

You can't expect a small QRP magloop to work as well as a 1/2-wave
vertical with 100 watts.

What makes you think it is not working as well as it ought to? What
have you compared it with?
----
Reg, G4FGQ


  #3   Report Post  
Old September 30th 05, 02:46 PM
Lee
 
Posts: n/a
Default


"Reg Edwards" wrote in message
...
==============================
There's almost certainly nothing the matter with it.

You can't expect a small QRP magloop to work as well as a 1/2-wave
vertical with 100 watts.

What makes you think it is not working as well as it ought to? What
have you compared it with?
----
Reg, G4FGQ

Hello Reg..
Took your advice and built a magloop......
I`m comparing the magloop to 5watts on a half-size sloping G5RV and i find
the magloop equivalent to the G5RV on R/X.whilst the magloop is inside the
house!!!..
I have a friend about a mile away that i chat to who hears me on the G5RV at
s30+ ......but, not at all on the magloop!!!!......
Why am i not being heard on the magloop???? :-/. H-E-L-P........

Lee.....G6ZSG.....




  #4   Report Post  
Old September 30th 05, 03:08 PM
Irv Finkleman
 
Posts: n/a
Default

Lee wrote:

"Reg Edwards" wrote in message
...
==============================
There's almost certainly nothing the matter with it.

You can't expect a small QRP magloop to work as well as a 1/2-wave
vertical with 100 watts.

What makes you think it is not working as well as it ought to? What
have you compared it with?
----
Reg, G4FGQ

Hello Reg..
Took your advice and built a magloop......
I`m comparing the magloop to 5watts on a half-size sloping G5RV and i find
the magloop equivalent to the G5RV on R/X.whilst the magloop is inside the
house!!!..
I have a friend about a mile away that i chat to who hears me on the G5RV at
s30+ ......but, not at all on the magloop!!!!......
Why am i not being heard on the magloop???? :-/. H-E-L-P........

Lee.....G6ZSG.....


You may have the null pointed at him. Are you able to work other
stations on the magloop?

Irv VE6BP
--
--------------------------------------
Diagnosed Type II Diabetes March 5 2001
Beating it with diet and exercise!
297/215/210 (to be revised lower)
58"/43"(!)/44" (already lower too!)
--------------------------------------
Visit my HomePage at http://members.shaw.ca/finkirv/index.html
Visit my Baby Sofia website at http://members.shaw.ca/finkirv4/index.htm
Visit my OLDTIMERS website at http://members.shaw.ca/finkirv5/index.htm
--------------------
Irv Finkleman,
Grampa/Ex-Navy/Old Fart/Ham Radio VE6BP
Calgary, Alberta, Canada
  #5   Report Post  
Old September 30th 05, 03:17 PM
Lee
 
Posts: n/a
Default


"Irv Finkleman" wrote in message
...
Lee wrote:

"Reg Edwards" wrote in message
...
==============================
There's almost certainly nothing the matter with it.

You can't expect a small QRP magloop to work as well as a 1/2-wave
vertical with 100 watts.

What makes you think it is not working as well as it ought to? What
have you compared it with?
----
Reg, G4FGQ

Hello Reg..
Took your advice and built a magloop......
I`m comparing the magloop to 5watts on a half-size sloping G5RV and i

find
the magloop equivalent to the G5RV on R/X.whilst the magloop is inside

the
house!!!..
I have a friend about a mile away that i chat to who hears me on the

G5RV at
s30+ ......but, not at all on the magloop!!!!......
Why am i not being heard on the magloop???? :-/.

H-E-L-P........

Lee.....G6ZSG.....


You may have the null pointed at him. Are you able to work other
stations on the magloop?

Irv VE6BP


I`ll try that tomorrow when i get it on the tower...thanks Irv.

Lee....G6ZSG.....

snip




  #6   Report Post  
Old September 30th 05, 03:21 PM
Lee
 
Posts: n/a
Default


"Irv Finkleman" wrote in message
...
Lee wrote:

"Reg Edwards" wrote in message
...
==============================
There's almost certainly nothing the matter with it.

You can't expect a small QRP magloop to work as well as a 1/2-wave
vertical with 100 watts.

What makes you think it is not working as well as it ought to? What
have you compared it with?
----
Reg, G4FGQ

Hello Reg..
Took your advice and built a magloop......
I`m comparing the magloop to 5watts on a half-size sloping G5RV and i

find
the magloop equivalent to the G5RV on R/X.whilst the magloop is inside

the
house!!!..
I have a friend about a mile away that i chat to who hears me on the

G5RV at
s30+ ......but, not at all on the magloop!!!!......
Why am i not being heard on the magloop???? :-/.

H-E-L-P........

Lee.....G6ZSG.....


You may have the null pointed at him.

Tried that just and got 5x8 with magloop in the house!!!! and only
5watts....

Lee....G6ZSG..

snip


  #7   Report Post  
Old September 30th 05, 06:34 PM
Irv Finkleman
 
Posts: n/a
Default

Lee wrote:

"Irv Finkleman" wrote in message
...
Lee wrote:

"Reg Edwards" wrote in message
...
==============================
There's almost certainly nothing the matter with it.

You can't expect a small QRP magloop to work as well as a 1/2-wave
vertical with 100 watts.

What makes you think it is not working as well as it ought to? What
have you compared it with?
----
Reg, G4FGQ

Hello Reg..
Took your advice and built a magloop......
I`m comparing the magloop to 5watts on a half-size sloping G5RV and i

find
the magloop equivalent to the G5RV on R/X.whilst the magloop is inside

the
house!!!..
I have a friend about a mile away that i chat to who hears me on the

G5RV at
s30+ ......but, not at all on the magloop!!!!......
Why am i not being heard on the magloop???? :-/.

H-E-L-P........

Lee.....G6ZSG.....


You may have the null pointed at him.

Tried that just and got 5x8 with magloop in the house!!!! and only
5watts....

Lee....G6ZSG..

Figured as much. You might want to try the loop in a horizontal configuration
for omnidirectional work. You'll probably find that you can operate it horizontally
just a few inches above the ground although I recommend a couple feet.

Irv VE6BP


--
--------------------------------------
Diagnosed Type II Diabetes March 5 2001
Beating it with diet and exercise!
297/215/210 (to be revised lower)
58"/43"(!)/44" (already lower too!)
--------------------------------------
Visit my HomePage at http://members.shaw.ca/finkirv/index.html
Visit my Baby Sofia website at http://members.shaw.ca/finkirv4/index.htm
Visit my OLDTIMERS website at http://members.shaw.ca/finkirv5/index.htm
--------------------
Irv Finkleman,
Grampa/Ex-Navy/Old Fart/Ham Radio VE6BP
Calgary, Alberta, Canada
  #8   Report Post  
Old October 1st 05, 03:36 AM
J. Mc Laughlin
 
Posts: n/a
Default

I second what Irv (VE6BP) has suggested. The modeling that I have done of
small loops (just plain loops, no magnetic materials involved) placed
horizontally (above earth) suggest the same pattern in all directions with a
significant dip towards the zenith - just what one's receiver likes in order
to receive signals from far away.

73 Mac N8TT

--
J. Mc Laughlin; Michigan U.S.A.
Home:
"Irv Finkleman" wrote in message
...
Lee wrote:

"Irv Finkleman" wrote in message
...
Lee wrote:

"Reg Edwards" wrote in message
...
==============================
There's almost certainly nothing the matter with it.

You can't expect a small QRP magloop to work as well as a 1/2-wave
vertical with 100 watts.

What makes you think it is not working as well as it ought to?

What
have you compared it with?
----
Reg, G4FGQ

Hello Reg..
Took your advice and built a magloop......
I`m comparing the magloop to 5watts on a half-size sloping G5RV and

i
find
the magloop equivalent to the G5RV on R/X.whilst the magloop is

inside
the
house!!!..
I have a friend about a mile away that i chat to who hears me on the

G5RV at
s30+ ......but, not at all on the magloop!!!!......
Why am i not being heard on the magloop???? :-/.

H-E-L-P........

Lee.....G6ZSG.....

You may have the null pointed at him.

Tried that just and got 5x8 with magloop in the house!!!! and only
5watts....

Lee....G6ZSG..

Figured as much. You might want to try the loop in a horizontal

configuration
for omnidirectional work. You'll probably find that you can operate it

horizontally
just a few inches above the ground although I recommend a couple feet.

Irv VE6BP


--
--------------------------------------
Diagnosed Type II Diabetes March 5 2001
Beating it with diet and exercise!
297/215/210 (to be revised lower)
58"/43"(!)/44" (already lower too!)
--------------------------------------
Visit my HomePage at
http://members.shaw.ca/finkirv/index.html
Visit my Baby Sofia website at http://members.shaw.ca/finkirv4/index.htm
Visit my OLDTIMERS website at http://members.shaw.ca/finkirv5/index.htm
--------------------
Irv Finkleman,
Grampa/Ex-Navy/Old Fart/Ham Radio VE6BP
Calgary, Alberta, Canada



  #9   Report Post  
Old October 1st 05, 06:49 AM
Lee
 
Posts: n/a
Default


"J. Mc Laughlin" wrote in message
...
I second what Irv (VE6BP) has suggested. The modeling that I have done of
small loops (just plain loops, no magnetic materials involved) placed
horizontally (above earth) suggest the same pattern in all directions with

a
significant dip towards the zenith - just what one's receiver likes in

order
to receive signals from far away.

73 Mac N8TT

--
J. Mc Laughlin; Michigan U.S.A.
Home:
"Irv Finkleman" wrote in message
...
Lee wrote:



I`ll try that Mac and see if it is worth the effort of a much larger
project.... like 10ft square multiband!!.

Thanks Mac & Irv..

Lee....G6ZSG......


  #10   Report Post  
Old October 1st 05, 08:14 AM
Reg Edwards
 
Posts: n/a
Default

Lee,

Using the loop indoors, at ground-floor level, at 20MHz, on a
groundwave path, is not inconsistent with what you get. Get it
high-up, outdoors, and it will make a big difference.

The capacitor is made from a length of coax. I wonder how long it is
and how it is located relative to the loop? Wherever it is, being
unbalanced coax it will unbalance the loop.

But what worries me, the very thin coaxial inner conductor is in
series with the main loop conductor. It may have a loss resistance
several times greater than the large diameter main loop. You could be
losing a lot of decibels.
----
Reg, G4FGQ.




Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
SkyWire Loop Antenna [Was: Wire loop.] Question RHF Shortwave 0 September 21st 05 10:15 AM
Eznec magnetic loop Dobar Dabar Antenna 0 September 3rd 05 05:33 PM
The "TRICK" to TV 'type' Coax Cable [Shielded] SWL Loop Antennas {RHF} RHF Shortwave 23 November 3rd 04 01:38 PM
Magnetic Loop antennas for LF and MF reception J M Noeding Shortwave 0 January 6th 04 04:53 AM
Should I run a Sky-wire loop? Rick Frazier Dx 9 September 8th 03 08:57 AM


All times are GMT +1. The time now is 10:10 AM.

Powered by vBulletin® Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright 2004-2017 RadioBanter.
The comments are property of their posters.
 

About Us

"It's about Radio"

 

Copyright © 2017