To: "Shellout" Alex - a couple of questions for you

Hi Ivan,
Now that was a real pity; what extreme bad luck. The guy was so clever and had some really unique ideas for improving an old technology.

I am well aware of liberties taken with advertising. I have here a picture of a pretty lady waering a nice knee-length dress, with the caption "perfect fit - all figures". Unfortunately they missed photoshopping out the heavy-duty bulldog stationary clips they used to make the fit perfect on the photo model.

But catch you later. Hafta get a few things done today.
BR Harry

Hi Harry,
the photo is like many other advertisements. It simply must contain both a beautiful YL and the product. Fortunately she does not use the MLA as a hula-hop!
A problem with those MLA antennas is that Olda had to stop further development after he got a cardio pacemaker. The strong EM field near the MLA might be dangerous for him.  

VBR from Ivan

Hi Ivan,
I have seen those designs, but it was many moons ago. I know that the MLA is very efficient, but it requires really low electrical resistance of the element due to the high currents. A larger loop means lower current, which is why my "(Nefab) packing crate" antenna was born. In the articles I saw the lower bands being covered by multiple loops.

I also had a little laugh at the photo of the YL with a 100-Watt rig, microphone in hand, sitting about 1/2 a metre from the loop

The frame antenna and magnetic loop antennas are both good, small antennas, but I always have the feeling that antennas have to be big: "metal in the air".

But thank you for the link. I will have a closer look at the articles.

My thoughts for a multi-band frame antenna was to use the same feed-loop/network for several resonant loops on the same frame. The only problem I can see is that they would be harmonically related, so the 14MHz antenna would efficiently radiate any spurious from the 3.5MHz or 7MHz feeds.

My little 3-Watt el-cheapo DSB rig was built on a budget and relied on the resonance of a loop antenna, and the X1M is not much of an improvement, even though it is "professionally" built (?).

But it is an interestinf subject. In all the areas of hamradio, antennas seems to be the area for the most ingenious development oportunities.

BR Harry

Hi Harry and all,
you wrote "I am still thinking about the multi-band loop antenna". Do you know the MLA-M and MLA-T antennas by OK2ER?
https://www.btv.cz/en/MLA-magnetic-loop-antenna

VBR from Ivan

Hi Alex, I have a couple of questions for you:

1 - You wrote that you have "a 'wonder areal' that covers everything from 160-6M"
Can you give a bit more info?
I once saw a "wonder aerial" that was basically a 5m vertical dipole with a matching unit at the bottom. the VSWR was almost perfect from 1.8MHz to 29.7MHz. It turned out that the efficiency was centered on 14MHz, but all other bands it didn't actually give any signal to speak of. All the reflected power was burned up in a dummy load resistor.

the only antenna I found that works wonders is the 4:1 balun and a 33%-66% tapped 1/2-wave dipole. If you add an 11% element to the 66%, then you get two bands for only 1/2 and element. Can be extended to cover 1.8, 3.6, 7.1, 14.2, and 28,4MHz bands with a very high radiation efficiency.

2 - Will you be on GB3MH tomorrow? Or can I call you directly on EL?

I used the forum as opposed to a PM because antennas are of interest to us all. I am still thinking about the multi-band loop antenna and I have a few ideas that I need some time to put into practice (when I am near a workshop and test gear). I am always seeking unexplored or forgotten effects that I can exploit.

BR Harry - EA/SM0VPO