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Old January 31st 07, 07:47 PM posted to rec.radio.shortwave
[email protected] r2000swler@hotmail.com is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 285
Default Long wire to SO-239 50 ohm?

On Jan 31, 3:38 am, "RHF" wrote:
On Jan 30, 6:38 pm, Telamon

wrote:
In article ,


David wrote:
http://www.minicircuits.com/pdfs/T8-1-X65.pdf


http://www.minicircuits.com/pdfs/T14-1-X65.pdf


You do not have the option of isolating the grounds on either model,
which would ordinarily be an advantage of the voltage type of
transformer.


--
Telamon
Ventura, California


Telamon - That is true. -but- Most so called "MLBs"
Magnetic Longwire Baluns are just such 'common
ground' Matching Transformers. iane ~ RHF
.
.
. .

Unless they have changed the internal wiring since 2001, the primary
and
secondary are completly isolated. MC transformers are NOT a good
choice for 'high" RF field locations. I don't know eaxctly at what
point it happens,
but I ran into big problems with 2nd harmonic distortion when I added
a ground
ring around my home to my ~70' wire antenna. I also expereinced a
number
of mix porducts. 1240+770, 1240-770 1240+2(770) etc. MiniCircuit
transformers
are nice and compact,but the very small size of the ferrite core
limits the
voltage because the micro cores saturate. There are many reports of MC
transfomres getting zapped by static. I never had that problem but the
IMD was a serious issue.

Wind you own on a suitable core.

Terry