Mike, your statement is no longer correct.
In the past, the manufacturers apparently all copied each other and used 4:1
baluns.
Many used the voltage balun because it was easier, or because they didn't
know any better.
In the meantime most of the manufacturers have switched and are now building
huge 1:1 current baluns into their tuners.
Check out the two big MFJ tuners (989 and 9982). The big one uses 4 cores!
Both MFJ symmetrical tuners use Maxwell 1:1 chokes.
Also, Palstar has ceased placing the balun inside the tuner and now offers
two external baluns, a 1:1 and a 4:1, both of them current baluns. There
can be cases where the 4:1 is a good balun, but then the load needs to be
very close to 200 Ohms, otherwise the 1:1 is a better choice.
Why did the manufacturers use upward conversion in transceivers for over 20
years?
Same reason as with the baluns.
They don't always know what they're doing.
And many just follow the leader.
73
Rick, DJ0IP
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Mike Bryce
Sent: Friday, July 12, 2013 5:15 PM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] OCF antennas evolution
Bob,
I can't explain it.
What I know is that every antenna tuner I've ever own, every one that is
currently in production, has a 4:1 balun inside.
if what you, rick, and everyone else is saying is right, why then don't the
manufactures of antenna matching devices (I never liked the term antenna
tuners as they don't tune the antenna) include 1:1 current balun instead of
4:1 voltage baluns.
from my cheap POS MFJ tuner in use for camping, to those $3K Palstar units,
they all come with 4:1 internal baluns.
Mike Bryce, WB8VGE
the heathkit shop
SunLight energy systems
J e e p
o|||||||o
On Jul 12, 2013, at 12:28 AM, Bob McGraw - K4TAX wrote:
> Then explain why a 4:1 balun is needed. Heck I might learn something.
>
> 73
> Bob K4tAX
>
>
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