Portable MW antenna?

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AmRadiant
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Portable MW antenna?

Post by AmRadiant »

Hello all, it can be a silly question, but I'll try...

What do you think about "portable" antenna for MW? Of course with a tiny fraction of power irradiated (with a tx about 500 mW- 1W out) and 200-300 meters (at best) of rx radius...

With a car, is better a (very) short vertical antenna (1.5 - 2 meters) with a big inductor, or a magnetic loop with diameter circa 1 mt (and a lot of coil)?

I'm curious about your opinion..
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pcs
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Post by pcs »

Not feasible, can't bend the laws of physics.
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AmRadiant
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Post by AmRadiant »

maybe I've defeated the law... but my tx 0.8W whit a dummy load in very open space make about 100-120 meters.

Coaxial cable was only 2 meters.
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Post by pcs »

Sorry, did not read carefully and did not see what range you wanted. As a general rule of thumb you need a big antenna to have good range on MW band. A couple hundred meters might work with a smaller type. Antenna tuner might be usefull.
https://www.pcs.si/test/index.php?cPath=21&

With this balun you only need to add wire to make a half wave dipole.
http://www.pcs-electronics.com/test/pro ... cts_id=729
It covers well below 1.8MHz no problem.
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Marko - PCS Electronics
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AmRadiant
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Post by AmRadiant »

many thanks for suggests, I've see some interesting objects, too :)
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AmRadiant
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Post by AmRadiant »

MFJ 945E 1.6-60MHz 300W antenna tuner can work in the upper region of MW (1593 and up)?

Do you import Autek antenna analyzer?

Thanks!
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Post by pcs »

Its usable under 1500 as well. We have what's there for now.
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Low Power Radio Guy
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Can't bend the laws of physics, but maybe squish them :-)

Post by Low Power Radio Guy »

One approach to reducing the physical length of the antenna is to play with the electrical length through the use of tuned loading coils. There are losses, of course (damn physics!) but you might find a trade off you'll accept.

Commercial units from Carl the AM Antenna Guy: http://antenna18431.tripod.com/antenna.htm

and Texas Bugcatcher: http://www.texasbugcatcher.com/cata/tbcspec.htm

and some arguing about it here: http://part15.us/node/1583

and here: http://part15.us/node/876

and here: http://part15.us/node/1605

and here: http://part15.us/node/1535

More info on my blog: http://lowpowerradio.blogspot.com/2008/ ... tenna.html

Which has links to this site as well =D>
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