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Portable MW antenna?

 
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Portable MW antenna?
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AmRadiant
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Joined: 02 Feb 2006
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Post Portable MW antenna? Reply with quote
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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Tue May 09, 2006 11:06 am View user's profile Send private message
pcs
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Post Reply with quote
Not feasible, can't bend the laws of physics.

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Tue May 09, 2006 12:24 pm View user's profile Send private message Visit poster's website
AmRadiant
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Post Reply with quote
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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Thu May 11, 2006 8:32 am View user's profile Send private message
pcs
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Post Reply with quote
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-electronics.com/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/product_info.php?cPath=21&products_id=729
It covers well below 1.8MHz no problem.

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Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
Thu May 11, 2006 11:46 am View user's profile Send private message Visit poster's website
AmRadiant
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Post Reply with quote
many thanks for suggests, I've see some interesting objects, too

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** FM is only a choice of fashion **
Fri May 12, 2006 8:41 am View user's profile Send private message
AmRadiant
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Post Reply with quote
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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** AM is a choice of life **
** FM is only a choice of fashion **
Fri May 12, 2006 8:48 am View user's profile Send private message
pcs
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Post Reply with quote
Its usable under 1500 as well. We have what's there for now.

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Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
Fri May 12, 2006 10:50 am View user's profile Send private message Visit poster's website
Low Power Radio Guy
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Post Can't bend the laws of physics, but maybe squish them :-) Reply with quote
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/2008/02/where-to-get-or-how-to-build-antenna.html

Which has links to this site as well Applause
Mon Feb 25, 2008 4:25 am View user's profile Send private message Visit poster's website
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