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Best MWDX antenna?

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RobRich:
I have used the AN-200 on my Kenwood R-2000 through the receiver's low-impedance input, though I used a variable gain preamp to handle the (huge?) mismatch. I only tend to do something like that if/when my outdoor antennas are disconnected, like during a storm, yet still wanting some radio nois... err, music or whatever in the background.

Suppose I could peak the AN-200 for an arbitrary MW frequency, then measure it with a VNA to get a better idea of its electrical characteristics. Maybe later tonight or tomorrow.

RobRich:
I did a *very quick test* with a NanoVNA-H4. There was some measurement bounce due to stray capacitance, as in likely my proximity to the setup.

Peaked the AN-200 at 850KHz. Approximately 950-j245 with a SWR over 20:1; give or take maybe 5 to 10 percent. Even with the error margin, that means a considerable mismatch to a lower impedance input for an already negative gain antenna.

In the case of the AN-200, a standard 9:1 balun likely would help considerably if direct connecting to a low-impedance receiver input, such as the usual ~50-ohm jack. Around $15 on eBay, or wind ya' own. An alternative could be a low-noise preamp as I previously noted using with my Kenwood desktop.

BTW, some desktop receivers have high-impedance inputs, though those are often just paths through 4:1 transformers to the usual internal low-impedance circuit inputs. That 4:1 could help, though a 9:1 or slightly higher ratio connected to the low-impedance input might prove superior for signal transfer.

As for portables.... yeah, those 1/8" and similar small inputs can be all over the place. I would start with a 4:1 or 9:1, though perhaps even no transformer at all might suffice. Huge YMMV. Otherwise just capacitance couple the AN-200 to the portable's internal MW ferrite loopstick antenna. ;)

pinto vortando:
If the OP really wants to investigate which MWDX antenna would work best for him, my suggestion would be to visit the International Radio Club of America (IRCA) website and check out the free reprints available covering all types of MW antennas.  Another source would be the National Radio Club (NRC) Antenna Manuals volumes 1 through 3 as well as their Design and Theory manuals covering Loops, and Beverage and Longwires...  five books in all that along with the IRCA reprints should be more than enough to satisfy the MWDX enthusiast.

~SIGINT~:
As mentioned earlier in post #11, I inserted a NooElec Flamingo AM filter which I purchased to overcome the strong RF signals from AM transmitters near to my location. I purchased both the enclosed versions of a Flamingo AM and a Flamingo FM for evaluation. Both filters are well built and assembled. I performed some bench tests at specific frequencies to test their frequency response. Both filters performed as advertised by the manufacturer and I am pleased with them. Below you will find the filter response charts based on the tests that I performed using my HP/Agilent instruments.

alpard:
They look excellent filters from the graphs. Thanks SIGINT.
I too sometimes suffer from overloading from an AM transmitter about 5 miles west of me.
So, if I point my loop to the West, then I get the strong AM signals from the transmitter all over the band popping up here and there everywhere.
This is a big problem.  So I have bought a set of Kiwa filters for MW and LW.  They are very old filters, and seem work OK.
Trouble is that now I do lots of listening for on MW DXing. When the MW stop filter is on, then the weak signals on MW gets blocked off.
So I must add some sort of switching to take out the filter when MW BCLing.  On SW BCLing, I need to switch on the MW blocking filter on.
I still hadn't add the switch, so ended up taking off the filter all together because SW condition is so poor, I hardly now listen to SW bands.
Just odd tuning around there, but mostly tune about MW bands for night time DXing. It has not been great either for DXing.
But I am still planning to add a 2 way switch for those filters.  The Kiwa filters are now out of production for some reason, but they are excellently built with heavy duty metal casings.

I wonder how you are using the filters and what your set up is. I guess it would depend on what bands you listen to most.

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