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Author Topic: LW/MW antenna for Kenwood R-2000  (Read 6327 times)

Offline flexoman61

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LW/MW antenna for Kenwood R-2000
« on: July 10, 2015, 2115 UTC »
I would like to start DXing LW and MW with my Kenwood R-2000. A loop would be best I guess but don't know much about them. My radio has SO239
antenna connection. Doesn't have internal mw/lw ferrite antenna if i'm not mistaken. I have 100' longwire I use on SW but probably not good for LW.

Loop antennas need to be rotated?
Indoors or outdoors?
Active or passive?
Feed line?

What should I try to hear on LW? Euro broadcast,
beacons?
Best time of day, year to listen?
Any advice would be appreciated.

Thanks, Don, flexoman61



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Offline ChrisSmolinski

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Re: LW/MW antenna for Kenwood R-2000
« Reply #1 on: July 10, 2015, 2135 UTC »
You should certainly be able to pick up a fair bit of MW and LW stations with a 100 ft longwire. I am not sure you'll have good luck with Euro broadcast stations, especially this time of the year, but beacons should easily be audible.

DX on MW and LW is a nighttime activity, although you should still be able to hear stations, even on LW, during the daytime. Give it a try!
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Offline jFarley

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Re: LW/MW antenna for Kenwood R-2000
« Reply #2 on: July 10, 2015, 2145 UTC »
Loop antennas need to be rotated?
Indoors or outdoors?
Active or passive?
Feed line?

What should I try to hear on LW? Euro broadcast,
beacons?
Best time of day, year to listen?
Any advice would be appreciated.

Thanks, Don, flexoman61

These are some general comments, which pertain to LW mainly:

Chris is right; a 100 foot longwire should be able to hear a lot.  

Unless you live in an electrically quiet house, the loop should be outdoors.  The amount of RFI at LW frequencies in the typical house is generally quite high.  The ability of a loop to depress RFI from a given direction is generally quite good, but noise tends to come from a number of sources within a house.

A loop which is not on a rotator can be very useful (it can always be swung around by hand to a target area), but having one on a rotator enables you to tap into the full potential of the loop.

Active or passive?  If you are rolling your own, its your call.  If you are purchasing a loop (such as a Wellbrook or Pixel SML) then it will be active.  BTW, the Wellbrook is a pretty good loop at LF.

Feedline: any good quality 50 or 75 ohm coax will generally have pretty low loss down at LF.  I use 75 ohm direct burial rated coax for most of my antenna runs.

I wouldn't invest a lot of money in an antenna if you were primarily interested in Euro broadcast; those are dropping like flies.  There are still a large number of LW beacons around (and very many difficult catches), even tho there is some decommissioning.  Generally best listening is from an hour or two after your local sundown until sun up, and late fall to early spring is the main season; thunderstorm noise can propagate long distance, and DX is hard in the summer.  More local beacons (within ~200 miles) can generally be well heard year round, some all day long.

Hope this helps!
« Last Edit: July 10, 2015, 2148 UTC by jFarley »
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Offline BoomboxDX

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Re: LW/MW antenna for Kenwood R-2000
« Reply #3 on: July 26, 2015, 0613 UTC »
100 ft longwire should work great on MW with a radio like the R2000.

I heard Japan on MW with an FRG7 through an 85 or so ft. wire a long time ago (I'm in the PNW -- but Japan's still a long ways away). I also had good luck with the FRG7 using a 150 folded low wire (about 4 ft off the ground).

Comm radios like the R2000 are RF sniffers.

If you really want to get into MW DXing, then a spiral or box loop would work (a loop would also work on LW if you put enough turns of wire on the frame), and you'd use a 'sense loop' wire that would be a single loop of wire in line with the other turns, and the ends would be wired to each side of the SO239.

You can find plans for such loops online. And most plans describe how to make and use the 'sense loop'.

But I'd just use the longwire until you decide if you want to go further.

The only thing a loop would give you is directionality on MW and LW. Important, yes, but you can still DX rather well with just a wire.
An AM radio Boombox DXer.
+ GE SRIII, PR-D5 & TRF on MW.
The usual Realistic culprits on SW (and a Panasonic).

 


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