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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.... |
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 |
"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..... |
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 |
"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 |
"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 |
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 |
"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...... |
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. |
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