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Mikey
26-07-2013, 23:16
Finally relented and bought one. Curious performance. On am this antenna is truly awesome.
When compared with my even my PK antennas, it reduces noise further and provides extra signal strength but on DRM the PKs outperform quite considerably but with one very intriguing distinction. When the AOR as switched on, tuned to the desired frequency (in this case AIR on 9950) and in close proximity to the PK it seemed to add SNR When switched off SNR going through the PK drops. I repeated this several times with the same result. I will be trying this again on other frequencies. In the meantime does anyone have any idea as to why this might be happening? I am a bit of an airhead when it comes to the technical stuff but it appears to be acting as something like an inductive lens. Similar to the way ferrite cores in MW radios interact. Does anyone have any thoughts on this?

mvs sarma
30-07-2013, 12:09
Great information, Mikey.

I have gone through the datasheet and user manual. In fact i admire M/S AOR for such nice design. It is now to be seen for any user reviews regarding its application in multistory Apartments.

Thanks for such data as treasure.

Mikey
30-07-2013, 18:39
Yes the design is excellent. Although I don't live in a block of flats I am surrounded by electro magnetic smog. The AOR definitely helps reduce this across most frequencies. With regards to the experiment above I tried this on the lower bands with my inductive loops. Here whilst the inductive loops generate more gain they also generate more noise. However when the inductive loops are used as a support they both reduce noise and increase gain. The problem is there doesn't seem to be any specific way on which they interact with each frequency and station needing
a different pattern. Does anyone know of any research work or any guide as to how to proceed?

mvs sarma
31-07-2013, 12:01
Yes the design is excellent. Although I don't live in a block of flats I am surrounded by electro magnetic smog. The AOR definitely helps reduce this across most frequencies. With regards to the experiment above I tried this on the lower bands with my inductive loops. Here whilst the inductive loops generate more gain they also generate more noise. However when the inductive loops are used as a support they both reduce noise and increase gain. The problem is there doesn't seem to be any specific way on which they interact with each frequency and station needing
a different pattern. Does anyone know of any research work or any guide as to how to proceed?

Did you see EH antennas and their design.It is interesting.
http://www.f5swn.fr/pages/eh2/eh2.php?lng=en

Mikey
31-07-2013, 21:13
Sadly I am using a tablet which does not support flash but googled and found ther website plus some claiming to debunk them. Bottom line is if one has unlimited space in the middle of nowhere then an outdoor antenna is almost always going to be better. If that does not apply then a shielded active antenna of good quality such as the PK or the AOR is essential. The AOR has the edge in terms of band coverage. The practical advantages of being able to use one compact antenna for the entire listening spectrum cannot be overstated. I also prefer to be able to fine tune antennas. The fact that with an adaptor it can be plugged into the antenna jack for medium and long wave is a real benefit when using my Newstar. I dont know if other users have experienced this but on my set the location of the ferrite bar makes induction difficult. If DRM becomes the standard on medium and long wave , the ability to tune the antenna for maximum SNR is going to be crucial. But as my previous posts have indicated amazing though it is, it is not a magic bullet. With regard to interaction with other loops, I spoke with an amateur radio friend of mine about my findings and he simply shrugged his shoulders and described the workings of loop antennas as something of a mystery. Thus pretty much reinforcing what I have found.

mvs sarma
02-08-2013, 08:08
Ok, Milkey, i get you.

Incidentally, please help indicate whether the circular pipe used to house is continuous or a slit one.if Aluminum pipe is continuous, except at bottom inside the box, does one expect induction for far places on MW as i was imagining a multi-turn winding inside the pipe.
For short wave , perhaps he used the AL pipe and switched caps in series,to bring the tuning into range of concerned band.

F1BJB
02-08-2013, 11:31
Hi
For what it's worth multi turns loop inside a shield is a very bad idea
There is very high capacity between turns and the tuning range is small with usual variable
capacitors.
Instead it is better to use a single turn and add a good fixed toroidal inductor in serial .
By switching this inductor the tuning range can be extended upward limited only by the physical
size of the main loop.

mvs sarma
03-08-2013, 02:28
Hi
For what it's worth multi turns loop inside a shield is a very bad idea
There is very high capacity between turns and the tuning range is small with usual variable
capacitors.
Instead it is better to use a single turn and add a good fixed toroidal inductor in serial .
By switching this inductor the tuning range can be extended upward limited only by the physical
size of the main loop.
Great. Thanks F1BJB, for the concept.