Parallel coax
In message , Jerry Stuckle
writes
On 9/28/2015 7:12 PM, John S wrote:
On 9/28/2015 1:51 PM, Jerry Stuckle wrote:
On 9/28/2015 1:42 PM, rickman wrote:
You said return loss increases with lower SWR. It does not.
It does.
Sorry, a lower SWR does not increase the amount of loss.
Of course it doesn't. No one said it did. It does the opposite, ie a
lower SWR gives less loss on the feeder.
Please cite a reliable reference that says it does. Even the table Rick
cited shows a negative value for return SWR.
What is this 'Return SWR'? I'm not familiar with it.
Do you mean Return Loss Ratio (RLR)? This is a simple, easily
measurable, and meaningful statement of how strong the returning
reflected signal is compared with the outgoing forward signal.
The reflected signal is a weaker version of the forward signal. It's
expressed as a loss, an attenuation, or relatively how much down the
level of the reflection is. You can express this as a numerical ratio -
the reflection coefficient (rho) - or (as often more convenient) rho in
dB.
As others have suggested, what is apparently a negative sign in the
chart is presumably more artistic licence than scientific accuracy. If
you lose $10, you don't say that you lost 'minus $10'. Similarly, when
you lose 10dB of signal, you don't say you lost 'minus 10dB'.
--
Ian
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