[Premium-Rx] FS: HF RECEIVER MULTICOUPLER (FROMDRAKE7-LINESTATION)

[George Georgevits]

Hi Guys,

Hmm... interesting observations and very well put.

BUT I thought the isolation of a hybrid splitter is only good if ALL the
terminating impedances are reasonably close to that intended by the design??
Given that antenna impedance can sometimes be all over the place (depending
on the antenna design), does anyone know what happens to the performance of
a hybrid splitter in terms of bandwidth and isolation under such conditions?

Needless to say it doesn't matter a hoot with a resistive splitter.

Cheers
George Georgevits
VK2KGG

> -----Original Message-----
> From: premium-rx-bounces at mailman.qth.net
> [mailto:premium-rx-bounces at mailman.qth.net]On Behalf Of Michael O'Beirne
> Sent: Wednesday, 25 April 2012 7:49 AM
> To: Clemens Paul
> Cc: PREMIUM-RX
> Subject: Re: [Premium-Rx] FS: HF RECEIVER MULTICOUPLER
> (FROMDRAKE7-LINESTATION)
>
>
>
> Dear Clemens
>
> Thank you for your email tonight.
>
> I agree entirely with your maths, but in some circumstances the
> much higher
> port- to-port isolation of the hybrid may not be needed, for
> example using
> two receivers at widely spaced frequencies in contrast to, say, critical
> receiver testing for IP3 where you need to achieve the maximum isolation
> between the two RF signal generators.
>
> 73s
> Michael
> G8MOB
>
> ----- Original Message -----
> From: "Clemens Paul" <cpaul at gmx.net>
> To: "Michael O'Beirne" <michaelob666 at ntlworld.com>
> Sent: Tuesday, April 24, 2012 6:58 PM
> Subject: Re: [Premium-Rx] FS: HF RECEIVER MULTICOUPLER (FROM
> DRAKE7-LINESTATION)
>
>
> > Hello Michael,
> >
> >>A resistive delta or splitter can be built even
> >> more cheaply for the cost of 3 resistors, 3 BNCs and a small metal box.
> >
> > This is really a cheap solution, but also in terms of performance.
> > 3dB more loss than a 3dB hybrid splitter and what is much more
> important,
> > the resistive splitter has a poor port isolation of only 12dB
> while a good
> > 3db hybrid splitter/combiner offers ~35dB.
> >
> > 73
> > Clemens
> > DL4RAJ
>
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