"Ian White, G3SEK" wrote:
> >That's why you find UHF connectors used on landmobile radios up
> >to 400 MHz and higher. The impedance bump, and loss, of a UHF
> >connector can be pretty much ignored up to 250 MHz, and often is
> >negligible above 250 MHz if the connector has partial air dielectric
> >in the female section.
>
> That's certainly true, and of course the UHF connectors are much more
> "monkey proof" than the N.
>
> The SWR problem is not with individual connectors but with multiples. On
> the back of the radio, the impedance bump can be compensated by design,
> for both the transmitter and the receiver. The problems arise further
> down the line if there are several of these connectors separated by odd
> lengths of coax. Murphy says the reflections will add in phase, and then
> you're into using special lengths of coax in order to get the SWR back
> under control.
This is true, one can "patch" any impedance back to nominal, but there
are losses, and the system goes narrow-band.
Ian ZS6BTE
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