Re: Why use a purpose built repeater box as a repeater rather than a transmitter, receiver, and controller tied (lashed) together?
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On Sun, Jan 24, 2021 at 8:36 AM Dan Woodie < kc8zum@...> wrote: Kevin,
I can assure you that all of my comments regarding desense are based on scientific data and my extensive training.? I would be happy to walk you through how to validate this if you would like.? If you can prove my statements incorrect I would be happy to post a retraction of my statements on the matter.? In many cases the level of desense I am referring to may not have any perceivable impact on operations but it does not mean it does not exist and is not measurable.? At some sites it is only a fraction of a dB.
Desense is not a logarithmic function of how well your equipment is setup?where incremental?improvements in the setup will cause?incremental?improvements of less desense. It is either there or not, and just a game of how many dB's your isolation is,?and rarely?would you have, say, 1/100 of a dB of desense. You either have enough isolation or you don't. If the isolation is enough, the desense is not there.?
On all repeaters I have setup, I put as weak of a signal that I can, measure the SINAD with TX OFF, and then measure the SINAD with TX ON, and observe any fractional changes. If it's setup right, there's no change. No popping on the RX when you key the TX, and nothing when you wiggle all the coax around.?
From David McGough Desense and site noise floor are 2 different things:??
Yes, my bad, and I was putting those two in the same category.
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