"It accepts RF input powers of up to 50 watts or so."
Do you mean transmitting. HOW is this a Transmitting LOOP? How does it connect to the radio for transmitting?
Also you have the radio in line with the plane of the loop, makes sense to me. However many youtube Videos show the radio at RIGHT ANGLES to the loop? Any comment on that. I assume it can work both ways. I have some small 9" loops and a Degen DE31MS mag loop and find in-line works best, but any comment appreciated.
Yes it's a transmitting loop. It's wired to the equipment, in this case an FT-817 transceiver. It isn't like a broadcast radio with an internal ferrite rod.
The feedline connects directly to the copper tubing which has a tapping point for the coax inner. Other builders use a second smaller loop instead.
Yep, I'm lucky I can now do that (moved to better QTH). For 160m I'll probably make a top-loaded vertical about 8m tall with a few radials. A loaded dipole for 80m & full-sized dipoles for 40 & 20.
But the previous QTH was a 1br flat with no private yard, no balcony, no courtyard. Either you used the magnetic loop indoors or you were QRT.
Greg - quite true - efficiency would be a few percent on 80m and well under 1% on 160m.
However I have worked VK6 & ZL on it on 80m and VK7 on 160m. Locally it does suprisingly well with 10 watts AM on 160m with good readable signals out to about 15km.
For transmitting it will never do as well as a full-sized antenna. But on a performance for size basis the magnetic loop comes out very well and the results are repeatable.
Small mag loops are one of ham radios best kept secrets.
I am building my third loop now. (video coming soon)
My recommendation though is not to put up with the 1% efficiency on 160 - thats hopeless.
I would run a small helical stick for TX and RX with the loop with auto change-over.
That way you can have the low noise RX characteristic of the loop and radiate a little bit more than 1 watt that you would be getting now with the loop and a TX power of 100W.
if you build one for 11 meters please let me know
29pu04 11 months ago
Are the magnets an amplifier or more so an antenna?
jonnyasprin 1 year ago
"It accepts RF input powers of up to 50 watts or so."
Do you mean transmitting. HOW is this a Transmitting LOOP? How does it connect to the radio for transmitting?
Also you have the radio in line with the plane of the loop, makes sense to me. However many youtube Videos show the radio at RIGHT ANGLES to the loop? Any comment on that. I assume it can work both ways. I have some small 9" loops and a Degen DE31MS mag loop and find in-line works best, but any comment appreciated.
gmcjetpilot 3 years ago
Yes it's a transmitting loop. It's wired to the equipment, in this case an FT-817 transceiver. It isn't like a broadcast radio with an internal ferrite rod.
The feedline connects directly to the copper tubing which has a tapping point for the coax inner. Other builders use a second smaller loop instead.
vk3ye 2 years ago
Yep, I'm lucky I can now do that (moved to better QTH). For 160m I'll probably make a top-loaded vertical about 8m tall with a few radials. A loaded dipole for 80m & full-sized dipoles for 40 & 20.
But the previous QTH was a 1br flat with no private yard, no balcony, no courtyard. Either you used the magnetic loop indoors or you were QRT.
vk3ye 3 years ago
Greg - quite true - efficiency would be a few percent on 80m and well under 1% on 160m.
However I have worked VK6 & ZL on it on 80m and VK7 on 160m. Locally it does suprisingly well with 10 watts AM on 160m with good readable signals out to about 15km.
For transmitting it will never do as well as a full-sized antenna. But on a performance for size basis the magnetic loop comes out very well and the results are repeatable.
vk3ye 3 years ago
Oh I agree 100%.
Small mag loops are one of ham radios best kept secrets.
I am building my third loop now. (video coming soon)
My recommendation though is not to put up with the 1% efficiency on 160 - thats hopeless.
I would run a small helical stick for TX and RX with the loop with auto change-over.
That way you can have the low noise RX characteristic of the loop and radiate a little bit more than 1 watt that you would be getting now with the loop and a TX power of 100W.
gW:-) OH2FFY
OH2FFY 3 years ago
Hi vk3ye , thanks for the video.
While the loop can tune across all HF bands , its efficiency below 7 MHz will be severely compromised.
Just by guesstimating it as 1.5 meters diameter its circumference is 4.7 meters.
Small loops are usually 1/10 wavelength in circumference.
Efficiency drops rapidly when you go smaller.
So this loops lowest recommended freq is the 47 meters.
40 meters being the closest band of operation.
Regards.
gregW:-) OH2FFY (ex VK6)
OH2FFY 3 years ago