Reflections about a remote mediumwave listeners station

Left: The terminating resistor of currently 820 ohms is waterproof in an HT tube. The connections are mounted on lamp terminals, without much effort to remove.

Center: Middle: The mast top in 7.50 meters, to the left of K9AY mast. An aluminum tube of 4 m length carries the tip, attached to the plum tree with clamps, freestanding.

Right: The 9:1 balun also resides in an HT pipe. The 4m long mast made of aluminum stands with only 2 guy wires in a ground pipe, which once served as a prop for a parasol. I still wrap my balune myself ...

For the 40 m long wire I use galvanized uninsulated electric fence wire with a diameter of 1mm. Source: 1000 m / < 33 €

Shot 1: Flag-Loop. The noise level is near -138 dBm, signal at -105.3 dBm. Direction 80°.
Shot 2: K9AY. The noise level is near -130 dBm, signal at -107.1 dBm. Direction 35°.
Shot 3: 50 m longwire. The noise level is near -127 dBm, signal at -108.5 dBm. Direction 30°. Connected two CMCC.

It looks a bit better than I suspected in the last post. The antennas were for comparison without preamplifier.

Note: A precise statement can not be derived from this, all antennas should have had the same direction.

The loop has a total circumference of almost 40 m and closes the gap between northeast and southeast of K9AY. The top of the mast is 7.50 m high. The direction of reception is 80° across the northern Indian subcontinent, via Southeast Asia, western Australia and the New Zealand South Island, huge targets for MW-DX.

The loop can be relocated with a few simple steps, if necessary. For Central America reception, only balun and resistance are reversed. As it is rather quiet without a suitable preamplifier, it is amplified by the RPA-2 from DX-Engineering. This brings 17 dBm, which is still 10 dBm below the noise figure of the the K9AY or the 50-longwire.

The flag loop was built according to the pattern of FO0AAA, but is twice as large. The audible front-to-back ratio is better than K9 and longwire, as is the directivity. It was the only antenna that audibly filtered Palangkaraya, Indonesia at 3325 kHz (31.9.2019, 17z).

So much wood for an antenna that is suspended relatively quickly. Some preliminary work is nevertheless necessary for the measurements to be correct.

More additions to the loop will bring time. Now I'm curious.

The horizontal loop is my second antenna type in the garden. The closely placed, meanwhile leafy trees, additionally complicate the mounting. The wire is 2 mm green-clad steel wire, which proved to be excellent tensile strength. He was purchased at the hardware store for 0,06 € / meters.