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Old March 19th 04, 01:37 PM
Dale Parfitt
 
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" Tuuk" wrote in message
...
Hi Dale
Are there any websites or information available to explain more detailed
about using antenna tuners for 2m ? I use two, one for 2m and one for
156megs frequently.

The antenna tuner does bring the reflected power down to almost 0 to the
radio and improves communications both receive and transmit. Could there

be
a hidden damage or danger?

Thanks

Hi,

There is no hidden danger. Remember though that a coaxial cable's loss is a
sum of its loss when matched ( 1:1) plus an additional loss caused by VSWR
on the line.
1. A tuner at the rig does nothing to alter the VSWR on the coaxial cable
2. at HF, where line loss is already low and most times insignificant, the
increased loss caused by the VSWR is tolerable- thus thier popularity
3. At VHF the matched line loss ( the mfg specs) may become appreciable
unless large diameter cable or short runs are employed- this is where the
additional loss on the line caused by VSWR (unchanged by a tuner) can add
up quickly

The ARRL Antenna Handbook and probably the Handbook itself has a graph that
shows the additonal loss caused by VSWR on the cable as a function of
matched cable loss.


Dale W4OP