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Re: AO-40 Test 05/08 (long)



I understand that his IS rocket science, but it does not have to be that
complicated. A bias T will work with NO real degradation. These converters
have so much gain that you will still have enough signal to drive the
sensitive receiver. Also, This is not a power amp where you are trying to
maintain the output power. The devices at the output of the converter are
class A and being driven at real low levels. Also, just because it has an F
connector it does not mean it is 75 ohm. Who knows what the real impedance
is at that port anyway.

Pieter

----- Original Message -----
From: "Edward R. Cole" <al7eb@ptialaska.net>
To: <AMSAT-BB@AMSAT.Org>
Sent: Thursday, May 10, 2001 11:19 AM
Subject: Re: [amsat-bb] AO-40 Test 05/08 (long)


> So if using a "tee" just run an old multiple of 1/4 wavelengths [times the
> coax velocity factor] of 75 ohm coax of equal length from each port.  Of
> course the TV-splitter is 75 ohm so you'll have a mismatch that way, too,
> though smaller.  I just ordered a Kuhne MKU-232A [35 dB gain] and will
feed
> two Drakes from it using the "tee" and 75 ohm Z-xfmr lines, thus having
> either 123 or 433.9 MHz IF's available.  Hope to be on by the weekend.
>
> Ed
> oops!  Just read down page and you said that already ;-)
>
> >From: "John Stephensen, KD6OZH" <kd6ozh@gte.net>
> >It does depend on the output device but a 25-ohm load will require more
> >current to acheive the same output voltage and any bandpass filters on
the
> >receiver inputs will not see 50-ohms so the responses will be altered.
> >
> >73,
> >
> >John
> >KD6OZH
>
>
>
> ----
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