DX Camp Iron Mountains 2021
560 m asl
Miloslav HUDEC

In the fall, in 2021, as every year, I spent several months in the Iron Mountains. Probably for the last time, because the owner of the cottage, which I always rent for years, raised the rental prices completely disproportionately. This is the entire cottage area and Agrofert was mentioned in the price announcement header. I don't think there's anything to explain anymore ...

This time I set myself the task of testing loop antennas. Active loops from NTI Bonito Megaloop FX and Cross Country Wireless. I ordered the loops, I paid. Megaloop FX worth over 14 thousand crowns, Cross Country Wireless also fit with postage up to 2000 CZK. In the meantime, I had a fairly lively conversation with Chris Moulding of Cross. He was very helpful, helpful and offered help and cooperation in the tests. It should be noted that the Bonito Megaloop FX loop antenna is taken as a kind of standard. Cross is actually the cheapest version of a serious loop antenna. And how the loops did over more than two months in the Iron Mountains I will state in the following lines.

As a receiver I only used my Sangean ATS 909 X. The loop has always been just one, hang up in free space, electronics about 1,5 meters above the ground. Loop length about 5.5 meters, triangular shape, loop area orientation−S - N. Power from batteries at 12 volts. Connection to the receiver which provided the coaxial cable
RG 58 10 meters long.

Left screw from NTI Bonito Megaloop FX, right hex socket. 

Some screws were very difficult to unscrew. The cross on the header was missing. Instead, I found only some dents ?! At the same time the threads in the box they were absolutely intact (I checked under a magnifying glass).

  First of all, I must mention the mechanical design of the loops. I examined both products in detail from the outside as well as from the inside. The NTI Bonito Megaloop FX loop was a big disappointment. I must write that I did not find a single healthy screw on it. Everything I will return everything to the seller. In the end, I didn't come back, I just remade!

Cross Country Wireless also had some flies, but many fewer. I replaced the BNC connector, which showed traces of the instrument. I just like the precise design! But this product showed quality handwork, hand soldering ... Just such a heart of Chris Moulding.

Both products are installed in plastic boxes of approximately the same dimensions. There are power switches for both. Cross Country Wireless has a power switch only as a printed circuit board with components and connectors. I'm not surprised at this price level. Megaloop FX has the ability to switch the gain of the amplifier in three steps and the ability to turn on the band stop, which suppresses the reception of commercial radio stations in the FM FM band. I didn't use any of that during the tests. Both products otherwise have approximately the same parameters (on paper), although Megaloop FX is still, or should be (again on paper) even better, especially in resistance to strong signals.

And how did the antennas behave in practice? When received from long waves, ie from 100 kHz to the end of the band of short waves, ie 29.999 kHz, they behaved exactly the same. Also when receiving commercial broadcasts in the FM FM band. I will therefore describe everything as one experience. I really didn't notice any differences between the products.

I wrote down a few frequencies that I found in various loop antenna tests that I wanted to try. So in addition to commercial radio stations common in these bands. I listened to all the frequencies listed very clearly, almost always on a five-way radio. I always made the reception after dark.

128.9 kHz Telecontrol 135.6 kHz HGA 22 147.4 kHz DWD DDN 47 198 kHz BBC
302.5 kHz DGPS Koblenz
7415 kHz China Radio Int., Beijing (in Czech)
14191 kHz USB amateur band live from around the world
- in the morning between 2 and 5 o'clock, always very good reception at DV and SV

     Interior design Cross Country Wireless

- band CB 27 MHz very good reception of local stations from Železné hory and wide surroundings
- I will not distribute the FM band, overall very good reception

I must mention one fact that I have noticed, and that is in the area of ​​long waves. Although the loops accept these ranges relatively well, the long wire wire antenna, even a few meters apart, simply surpasses them. Often very significantly. The condition, however, is a quality balun, unun, best made at home. A good income in the lowest zones is definitely not ensured by commercial products, e.g. LWB 1 and / or the widely used MTFT. The reason for the lower efficiency of loop antennas is the small loop circumference. Just loop diameter usually 1 meter is not enough, it is too small! And with a lower input signal, the amplifier's own noise is applied all the more! However, in a noisy environment, quality loop antennas are certainly a good alternative. And unfortunately, the interference is constantly increasing!
I will mention about the Sangean ATS 909 X.
It was obvious that with active loops worked slightly behind within their borders options. Sometimes I recorded parasitic incomes in places where there should be nothing.
I believe that if you used a better receiver or transceiver, the reception would be better.
Absolutely disappointed borrowed receiver Tecsun PL 880, which he could no longer handle the strong signal.
 
Self-test of loop antennas. A high-quality double line was used for the loop, the two cores at the ends joined to achieve a larger diameter.

  NTI Bonito Megaloop FX interior design

And the end of the test

Loop antennas yes, if we are in an environment that is strongly disturbed. However, if we are able to eliminate the interference by the position of the antenna, it pays to stretch the long wire antenna. It doesn't even have to be long. A wire with a length of only 10 meters provides a very good reception. However, the condition is a good balun, unun.

As for loop antennas, the NTI Bonito Megaloop FX is extremely overpriced. You only pay the brand, nothing more. On the contrary, Cross Country Wireless offers very good performance for very reasonable money. We get quite a lot of music for little money!

Antenna links:

https://www.bonito.net/hamradio/en/mega−loop−fx/ 

http://www.crosscountrywireless.net/loop_antenna_amplifier.htm

 In the Iron Mountains, I also had the opportunity to try this very well-preserved and beautiful RFT receiver. I sat with him in the evenings for about a week. Beautiful nostalgia. Many years ago, I started with the TESLA HIFI 3606A receiver. It turned out how I idealized these receivers over the years. Sangean ATS 909 X did not even come close in reception quality. However, even so it was beautiful sitting and listening ...