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Old January 10th 06, 03:48 PM posted to rec.radio.amateur.antenna,sci.electronics.basics
Cecil Moore
 
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Default Dipoles and the rig's RF ground...

Reg Edwards wrote:
The name "Transmission line" has been conveniently changed to "Series
Section Transformer".

But it still has standing waves on it far higher than what you claim
for all bands. And don't standing waves increase loss on SST's just as
much as they do on transmission lines?


As you know, standing waves increase loss on SST's just as much
as they do on transmission lines *OF THE SAME LENGTH*. For instance,
on 3.8 MHz, that 300 ohm series section transformer on a G5RV has
an SWR of about 20:1 and a line loss of about 0.7 dB, about 12% of
one S-unit. That's a small price to pay for multi-band operation.
And using Wireman #554 (like I do) instead of 300 ohm twinlead will
cut those SST losses down to 0.37 dB, about 6% of an S-unit.

I once set up an 80 feet dipole without a series section transformer.
Unsurprisingly - it worked. ;o)


If you fed it with ladder-line, you fed it with a long series
section transformer. :-)
--
73, Cecil http://www.qsl.net/w5dxp