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Old March 19th 05, 08:32 PM
Jack Painter
 
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"Richard Clark" wrote
"Jack Painter"
wrote:

would a voltage balun be more effective in any of those conditions?


Hi Jack,

The typical Voltage BalUn is constructed in such a way that one lead
violates the isolation offered by the Current BalUn method. There are
examples found for the same application of the 4:1. One is the
Guanella, the other is the Ruthroff. If you examine the Ruthroff
model, you will notice that one lead of the load (antenna) is
connected directly to the source without a choking intervention. On
the other hand, both leads are choked by the Guanella.

By common usage, the Guanella is generally described as a Current
type, where as the Ruthroff is described as a Voltage type BalUn.
Current or Voltage, the more important feature is in the choking.

73's
Richard Clark, KB7QHC


Thanks Richard. I have never seen the internal construction of the Radio
Works BalUn, but it is claimed to be a current-type device. It's function
as a choke was the only reason for including it in the designs of my antenna
systems. I see that Reg as well as yourself remind us that is indeed their
primary purpose. Too bad so many may have been fooled into using
voltage-type baluns when that appears to be an inappropriate choice for may
applications. I was curious what applications would benefit from such a
voltage-balancing device.

Jack