Jon writ:
>>The only thing a tuner does is to
>>>essentially act as a buffer between your exciter and your load. It will
>>>not improve a bad antenna. If the antenna has a 15:1 VSWR without the
>>>tuner, it still has it with the tuner. You just don't see it.
>>>
>>? Thick sliced bologna. . . If a 15 to one / 750 ohm antenna is
>>connected to a matching network/antenna tuner, the 750-ohms is
>>transformed to 50-ohms +/- j0 ohms.
>
>Rich, it is NOT bologna!
"I am not a crook".
"I did not have sex with that women".
>The impedance at the feedpoint of the antenna
>does NOT change because you put a tuner in the line.
? I did not say that the 750 ohm feed Z changed. I said that it was
transformed to 50 ohms by the matching network. // I mentioned nothing
about a feedline. The antenna could have been an end-fed halfwave
(Hertz) - which has no feedline. If a feedline is used - say with a
fullwave dipole - adding a halfwave-length feedline of whatever Z would
change nothing.
>If you think that it
>does, I have a bridge to sell you.
price and availability?
>The tuner DOES transform the impedance
>at the tuner to look like 50 Ohms so that it looks proper to you exciter.
>
>Yes, the 750 Ohms is transformed to 50 Ohms, BUT THE ANTENNA IMPEDANCE AT
>THE FEEDPOINT IS STILL 750 OHMS!!!
? zzzzzzz
>You still have that 15:1 VSWR between
>the antenna and the output of the tuner.
With a Hertz antenna, there is no feedline. To have an SWR, you must
have a feedline.
>
>>
>> >........I wouldn't worry about your variances in SWR readings. It's
>>>really just to give you an idea of what kind of power is coming back at
>>>your rig. Personally, I'd match it so that the PA sees the best possible
>>>match. This means that your tuner and whatever you have on the output of
>>>your PA are optimally matched. Who cares what the SWR meter in the tuner
>>>sees. The output of the tuner is going to have a high VSWR anyhow!
>>>Matching this way will cause you to put the maximum available power into
>>>the tuner instead of reflecting 2.5% of it back to the amp.
>>>
>>? However, without a tuner, the 2.5% gets reflected back to the antenna.
>>
>
>No, that's not correct.
? Where does the reflection go after it arrives at the amp. output
terminal? It is my opinion that the reflection heads back toward the
antenna.
- later
- Rich..., 805.386.3734, www.vcnet.com/measures.
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