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Mag Loop from MFJ

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NJ8M

Mag Loop from MFJ

They are unreliable pieces of junk. The housing does not protect the
capacitors that are in house made and bugs can crawl into the housing and
short them out. Secondly, the plastic housing in Kansas will be destroyed
by the sun. The best thing about the loop is the loop itself. It is built
well. The caps are cheap. Tuning the bastard is not consistent, not fast,
and highly touchy. The only loop worth purchasing is the Ciro Mazzoni loop
from Italy sold by DX engineering. It will take abuse and has an excellent
tuning feature that will follow your radio. Each time you change freq with
the MFJ it is a task to get it to tune again. A friend of mine bought one
and it was soon offered to me for $100. Then he became so frustrated with
it that he wanted me to take it for free if I would dig the post out of the
ground he mounted it on. I Passed knowing that any dipole would blow it
away. Even an end fed random wire will beat it in performance if put up
right. In the end there are many cheaper options that work far better than
the MFJ mag loop.

73,
Morgan NJ8M

BS + MS + $2.98 = COFFEE
Real Life Experience = Priceless, says the man who set his back yard on
fire with a breadboard tuner loading a 160 meter inverted L with 1000
watts. LOL
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AB7WE

Re: Mag Loop from MFJ

I had to take my new MFJ mag loop apart, re-align & tighten the capacitor plates, and adjust the end stop switch so that the motor would turn the cap all the way. After that it worked well as an indoor antenna hung behind a large window in high-rise condo. Retuning after changing freq is tiresome, but less of an issue if one is staying on the same freq (FT8, etc) and only needing to retune when changing bands. I received good signal reports and worked all states on FT8, but sold it after moving back to a house and needing a proper outside antenna.

Phil AB7WE

________________________________
From: [hidden email] <[hidden email]> on behalf of Morgan Bailey <[hidden email]>
Sent: Monday, January 18, 2021 3:38 PM
To: [hidden email] <[hidden email]>; [hidden email] <[hidden email]>
Subject: [Elecraft] Mag Loop from MFJ

They are unreliable pieces of junk. The housing does not protect the
capacitors that are in house made and bugs can crawl into the housing and
short them out. Secondly, the plastic housing in Kansas will be destroyed
by the sun. The best thing about the loop is the loop itself. It is built
well. The caps are cheap. Tuning the bastard is not consistent, not fast,
and highly touchy. The only loop worth purchasing is the Ciro Mazzoni loop
from Italy sold by DX engineering. It will take abuse and has an excellent
tuning feature that will follow your radio. Each time you change freq with
the MFJ it is a task to get it to tune again. A friend of mine bought one
and it was soon offered to me for $100. Then he became so frustrated with
it that he wanted me to take it for free if I would dig the post out of the
ground he mounted it on. I Passed knowing that any dipole would blow it
away. Even an end fed random wire will beat it in performance if put up
right. In the end there are many cheaper options that work far better than
the MFJ mag loop.

73,
Morgan NJ8M

BS + MS + $2.98 = COFFEE
Real Life Experience = Priceless, says the man who set his back yard on
fire with a breadboard tuner loading a 160 meter inverted L with 1000
watts. LOL
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k6dgw

Re: Mag Loop from MFJ

In reply to this post by NJ8M

Ciro Mazzoni loops run from $1,800-$2,500 at DX engineering. They seem
to use direct in place of inductive coupling. The automated tuning is
cool, but requires a control cable to the antenna as well as coax. My
experience with MFJ resembles Morgan's, I wouldn't call them junk but
they don't stand up well outdoors. SML's, if the loop plane is
vertical, tend to be insensitive to ground [i.e. height AGL] and
surrounding objects if their permeability is close to 1.0. My
permeability must be close to 1.0 because I sit under it and can reach
up and tune it, and my presence doesn't seem to affect it. The Alexloop
Walkham has a reduction gear on the capacitor but it's not enough and
below 20 m the adjustment gets very touchy.

My HOA antenna is a WOOF [Wire On Organic Fence], a 135' wire strung on
plastic electric fence insulators on a wooden fence, about 6' AGL, and
end fed through a 9:1 autotransformer. Works all HF bands, good for a
KW [I run a K3/100], and runs circles around the Alexloop. See
myantennas.com

There is another disadvantage to portable mag loops ... in a public
place, you may find yourself speaking with a law officer, it seems there
a number of folks that will call the cops on on the guy with headphones
sitting at the picnic table in the park.😉

73,

Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 1/18/2021 3:38 PM, Morgan Bailey wrote:

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Mooneer Salem

Re: Mag Loop from MFJ

In reply to this post by NJ8M

FWIW, mine has worked fairly well (on the roof of my second floor condo)
since last year, moreso on 20 than 40 meters. At the time I was honestly
not sure how else I'd have been able to have something permanently set up
outdoors (unfortunately needed due to stucco construction) and HOA approved
otherwise*, so there's definitely a market for them. In my experience, the
"band change" buttons stop tuning when the SWR gets close--even when
retuning within the same band--and the slow tune buttons seem to have
enough granularity to allow someone to stop when the dip in reflected power
happens. If one's loop doesn't do that, there's a pot that one can adjust
inside the control box to fix that particular issue.

Anyway, this thread does remind me that I should go back up and confirm the
conductor diameter for sure; I had been assuming something close to 1"
before but it's likely smaller than that.

-Mooneer K6AQ

* I only found out about the Isotrons after setting up the loop.
Considering the supposed bandwidth of the 40m and up ones, it's possible
I'd have gone with those instead (since less effort is always nice).

On Mon, Jan 18, 2021 at 3:43 PM Morgan Bailey <[hidden email]> wrote:

> They are unreliable pieces of junk. The housing does not protect the
> capacitors that are in house made and bugs can crawl into the housing and
> short them out. Secondly, the plastic housing in Kansas will be destroyed
> by the sun. The best thing about the loop is the loop itself. It is built
> well. The caps are cheap. Tuning the bastard is not consistent, not fast,
> and highly touchy. The only loop worth purchasing is the Ciro Mazzoni loop
> from Italy sold by DX engineering. It will take abuse and has an excellent
> tuning feature that will follow your radio. Each time you change freq with
> the MFJ it is a task to get it to tune again. A friend of mine bought one
> and it was soon offered to me for $100. Then he became so frustrated with
> it that he wanted me to take it for free if I would dig the post out of the
> ground he mounted it on. I Passed knowing that any dipole would blow it
> away. Even an end fed random wire will beat it in performance if put up
> right. In the end there are many cheaper options that work far better than
> the MFJ mag loop.
>
> 73,
> Morgan NJ8M
>
> BS + MS + $2.98 = COFFEE
> Real Life Experience = Priceless, says the man who set his back yard on
> fire with a breadboard tuner loading a 160 meter inverted L with 1000
> watts. LOL
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>

Mooneer Salem

Re: Mag Loop from MFJ

In reply to this post by k6dgw

Hi Fred,

On Mon, Jan 18, 2021 at 4:31 PM Fred Jensen <[hidden email]> wrote:

> There is another disadvantage to portable mag loops ... in a public
> place, you may find yourself speaking with a law officer, it seems there
> a number of folks that will call the cops on on the guy with headphones
> sitting at the picnic table in the park.😉

Fortunately I've never had that issue but I did get a fire truck pulling up
next to me at Fiesta Island here in San Diego once (with one of the
firefighters being interested in my full size 20 meter vertical and asking
questions about my radio setup). That was pretty cool.

(MFJ ~17' telescoping whip screwed into a Buddipole Versa-Tee + 1-2 raised
radial wires cut to quarter wavelength at 20 meters. With a KX3 driving it,
of course.)

Thanks,

-Mooneer K6AQ
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k6dgw

Re: Mag Loop from MFJ

Happened to me a couple of times, I tell them ... with a big grin ...
that I'm "ET incognito calling home." Reactions have been varied

73,

Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 1/18/2021 4:45 PM, Mooneer Salem wrote:

> Hi Fred,
>
> On Mon, Jan 18, 2021 at 4:31 PM Fred Jensen <[hidden email]> wrote:
>
>> There is another disadvantage to portable mag loops ... in a public
>> place, you may find yourself speaking with a law officer, it seems there
>> a number of folks that will call the cops on on the guy with headphones
>> sitting at the picnic table in the park.😉
>
> Fortunately I've never had that issue but I did get a fire truck pulling up
> next to me at Fiesta Island here in San Diego once (with one of the
> firefighters being interested in my full size 20 meter vertical and asking
> questions about my radio setup). That was pretty cool.
>
> (MFJ ~17' telescoping whip screwed into a Buddipole Versa-Tee + 1-2 raised
> radial wires cut to quarter wavelength at 20 meters. With a KX3 driving it,
> of course.)
>
> Thanks,
>
> -Mooneer K6AQ
>

Elecraft mailing list

Re: Mag Loop from MFJ

In reply to this post by Mooneer Salem

I can’t speak to the MFJ but I do have a 3 ft diameter AlexLoop that I imagine is similar at a very high level and in addition as M0SNA I have the Ciro Mazzoni Baby Loop which can handle a wicked amount of power and is built like an Italian sports car. One thing that surprises me about magnetic loops is there high price.

Anecdotally, my AlexLoop did an amazing job on 10-20m and was a really crap shoot on 40m. I think the numbers quoted might be very optimistic as I think on 40m (and 30m) a 3 ft magnetic loop is horribly inefficient.

One thing I learnt from talking to Ciro Mazzoni is that the lobes created by these smaller magnetic loops are pretty high of the ground possibly with a concentration of power at 50-60 degrees off the horizon. That aside, my AlexLoop surprised me in early 2016 during NPOTA as I managed phone WAS using 10w portable from the San Francisco area. My Ciro Baby Loop seems to have no issue with stations out 2-3K miles but beyond that its a really luck of the draw and clearly tied to bands and propagation. From the UK on 20m and 40m I struggle to get East Coast stations.

I’m happy to have the Magnetic Loops in my arsenal but would pick another antenna if circumstances dictated.

Here is a short write up on my AlexLoop which I do like…..https://nomadic.blog/2018/09/20/oh-ye-of-little-faith-my-journey-with-an-alexloop/ <https://nomadic.blog/2018/09/20/oh-ye-of-little-faith-my-journey-with-an-alexloop/>

Paul
W6PNG/M0SNA
www.nomadic.blog <http://www.nomadic.blog/>

> On Jan 18, 2021, at 4:40 PM, Mooneer Salem <[hidden email]> wrote:
>
> FWIW, mine has worked fairly well (on the roof of my second floor condo)
> since last year, moreso on 20 than 40 meters. At the time I was honestly
> not sure how else I'd have been able to have something permanently set up
> outdoors (unfortunately needed due to stucco construction) and HOA approved
> otherwise*, so there's definitely a market for them. In my experience, the
> "band change" buttons stop tuning when the SWR gets close--even when
> retuning within the same band--and the slow tune buttons seem to have
> enough granularity to allow someone to stop when the dip in reflected power
> happens. If one's loop doesn't do that, there's a pot that one can adjust
> inside the control box to fix that particular issue.
>
> Anyway, this thread does remind me that I should go back up and confirm the
> conductor diameter for sure; I had been assuming something close to 1"
> before but it's likely smaller than that.
>
> -Mooneer K6AQ
>
> * I only found out about the Isotrons after setting up the loop.
> Considering the supposed bandwidth of the 40m and up ones, it's possible
> I'd have gone with those instead (since less effort is always nice).
>
>
> On Mon, Jan 18, 2021 at 3:43 PM Morgan Bailey <[hidden email]> wrote:
>
>> They are unreliable pieces of junk. The housing does not protect the
>> capacitors that are in house made and bugs can crawl into the housing and
>> short them out. Secondly, the plastic housing in Kansas will be destroyed
>> by the sun. The best thing about the loop is the loop itself. It is built
>> well. The caps are cheap. Tuning the bastard is not consistent, not fast,
>> and highly touchy. The only loop worth purchasing is the Ciro Mazzoni loop
>> from Italy sold by DX engineering. It will take abuse and has an excellent
>> tuning feature that will follow your radio. Each time you change freq with
>> the MFJ it is a task to get it to tune again. A friend of mine bought one
>> and it was soon offered to me for $100. Then he became so frustrated with
>> it that he wanted me to take it for free if I would dig the post out of the
>> ground he mounted it on. I Passed knowing that any dipole would blow it
>> away. Even an end fed random wire will beat it in performance if put up
>> right. In the end there are many cheaper options that work far better than
>> the MFJ mag loop.
>>
>> 73,
>> Morgan NJ8M
>>
>> BS + MS + $2.98 = COFFEE
>> Real Life Experience = Priceless, says the man who set his back yard on
>> fire with a breadboard tuner loading a 160 meter inverted L with 1000
>> watts. LOL
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
>>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

David Christ

Re: Mag Loop from MFJ

In reply to this post by k6dgw

I’ll have to remember that if someone asks about my K4KIO Hex antenna

David K0LUM

> On Jan 18, 2021, at 6:54 PM, Fred Jensen <[hidden email]> wrote:
>
> Happened to me a couple of times, I tell them ... with a big grin ... that I'm "ET incognito calling home." Reactions have been varied
>
> 73,
>
> Fred ["Skip"] K6DGW
> Sparks NV DM09dn
> Washoe County

> I did get a fire truck pulling up
> next to me at Fiesta Island here in San Diego once (with one of the
> firefighters being interested in my full size 20 meter vertical and asking
> questions about my radio setup). That was pretty cool.
>
>
>
> Thanks,
>
> -Mooneer K6AQ

Doug Turnbull

Re: Mag Loop from MFJ

In reply to this post by NJ8M

Dear OMs, I have had much success using the Brazilian Alexloop. It is convenient, unobtrusive, easily packed and does a far better job than I would dream. I use it travelling with KX2 or KX3. ITt has been used indoors in a WPX contest for 233 Qs, from inside my sister's Connecticut house. A third of the Qs were with EU. Yes an end fed half wave will do better. I can not always deploy such an antenna. For me the AlexLoop is easy to use and does the impossible while on my travels. A QRP antenna for sure.73 Doug EI2CNSent from my Galaxy
-------- Original message --------From: Morgan Bailey <[hidden email]> Date: 18/01/2021 23:42 (GMT+00:00) To: [hidden email], [hidden email] Subject: [Elecraft] Mag Loop from MFJ They are unreliable pieces of junk. The housing does not protect thecapacitors that are in house made and bugs can crawl into the housing andshort them out. Secondly, the plastic housing in Kansas will be destroyedby the sun. The best thing about the loop is the loop itself. It is builtwell. The caps are cheap. Tuning the bastard is not consistent, not fast,and highly touchy. The only loop worth purchasing is the Ciro Mazzoni loopfrom Italy sold by DX engineering. It will take abuse and has an excellenttuning feature that will follow your radio. Each time you change freq withthe MFJ it is a task to get it to tune again. A friend of mine bought oneand it was soon offered to me for $100. Then he became so frustrated withit that he wanted me to take it for free if I would dig the post out of theground he mounted it on. I Passed knowing that any dipole would blow itaway. Even an end fed random wire will beat it in performance if put upright. In the end there are many cheaper options that work far better thanthe MFJ mag loop.73,Morgan NJ8MBS + MS + $2.98 = COFFEEReal Life Experience = Priceless, says the man who set his back yard onfire with a breadboard tuner loading a 160 meter inverted L with 1000watts. LOL______________________________________________________________Elecraft mailing listHome: http://mailman.qth.net/mailman/listinfo/elecraftHelp: http://mailman.qth.net/mmfaq.htmPost: mailto:[hidden email] list hosted by: http://www.qsl.netPlease help support this email list: http://www.qsl.net/donate.htmlMessage delivered to [hidden email]
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n0uk

Re: Mag Loop from MFJ

In reply to this post by David Christ

FWIW - I invested in an MFJ-1786 when we moved into our apartment 6 1/2 years ago. Since then, kit has been out on our 5th floor balcony in central Minneapolis year round, easily standing up to both Minnesotan Winters and Summers with aplomb.

It has not ceased to work in that time and has netted me ~150 DXCC’s on all bands from 30 through 10 metres. Most of my work is CW by preference although I did break a pile-up a couple of years back to work VP8 on 20m SSB from an ATNO.

To say I am pleased with its performance and capability may be understatement of the decade! I am absolutely gobsmacked at how well such a physically small antenna plays on HF and am willing to stand up for MFJ (at least in this particular case).

YMMV, of course…

Chris Cox, N0UK
[hidden email]

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