January 27th 07, 01:16 AM
posted to rec.radio.shortwave
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First recorded activity by RadioBanter: Jul 2006
Posts: 4,494
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Long wire to SO-239 50 ohm?
In article ,
David wrote:
On Fri, 26 Jan 2007 02:03:04 GMT, Telamon
wrote:
In article ,
David wrote:
On Thu, 25 Jan 2007 03:06:28 GMT, Telamon
wrote:
If you use a cable TV Balun you'll get a quick and dirty 4:1
transformer and a marked improvement.
http://www.radioshack.com/product/in...3912&cp=&sr=1&
ori
gkw=matching+transformer&kw=matching+transformer&p arentPage=search
Those don't work well below 10 MHz. 15 MHz and higher they are OK.
How do you know?
I tested them.
What is the low frequency limiting component?
I didn't go as far as that. This unit is made of a ferrite core and a
couple of very small value capacitors. I would guess the core was the
problem.
I've reverse engineered a bunch of them. The ones with caps are very
rare.
The one you referenced has the capacitors. I would go with another model.
--
Telamon
Ventura, California
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